update to Java 13, fixing build

Testcontainers

aws/aws-rds-hello-world/Dockerfile

@@ -0,0 +1,5 @@
+FROM openjdk:8-jdk-alpine
+ARG JAR_FILE=build/libs/*.jar
+COPY ${JAR_FILE} app.jar
+ENTRYPOINT ["java","-jar","/app.jar"]
+EXPOSE 8080

aws/aws-rds-hello-world/README.md

@@ -0,0 +1,25 @@
+# RDS Hello World Application
+
+This is a simple Spring Boot application which requires access to a PostgreSQL database.
+
+The application has a single endpoint `/hello` which prints out if the database connection was successful.
+
+Get it in a Docker image via `docker pull reflectoring/aws-rds-hello-world`.
+
+Use the image instead of your real application to test AWS CloudFormation stacks which need access to a database.
+
+## Testing AWS RDS connectivity with this application
+
+1. Create an RDS PostgreSQL database with the AWS console.
+2. Note the endpoint of your RDS database in the AWS console.
+3. Deploy the Docker container `reflectoring/aws-rds-hello-world` into AWS instead of your real application (this could be via a CloudFormation stack, manually, or however you are deploying your app).
+4. Configure your deployment in a way that Docker will pass the coordinates to your RDS database as environment variables, equivalent to this command:
+    ``` 
+    docker run \
+      -e SPRING_DATASOURCE_URL=':'<RDS-ENDPOINT>:5432/postgres \
+      -e SPRING_DATASOURCE_USERNAME=<USERNAME> \
+      -e SPRING_DATASOURCE_PASSWORD=<PASSWORD> \
+      -p 8080:8080 reflectoring/aws-rds-hello-world
+    ```
+5. If the Spring Boot application can connect to the database, it will start up sucessfully and serve a message on the endpoint `/hello`.
+

aws/aws-rds-hello-world/build.gradle

@@ -0,0 +1,31 @@
+plugins {
+	id 'org.springframework.boot' version '2.2.4.RELEASE'
+	id 'io.spring.dependency-management' version '1.0.9.RELEASE'
+	id 'java'
+}
+
+group = 'io.reflectoring'
+version = '0.0.1-SNAPSHOT'
+sourceCompatibility = '1.8'
+
+repositories {
+	mavenCentral()
+}
+
+dependencies {
+	implementation 'org.springframework.boot:spring-boot-starter-web'
+
+	// database
+	implementation 'org.flywaydb:flyway-core'
+	implementation 'org.springframework.boot:spring-boot-starter-data-jdbc'
+	runtimeOnly 'org.postgresql:postgresql'
+	testRuntimeOnly 'org.postgresql:postgresql'
+
+	testImplementation('org.springframework.boot:spring-boot-starter-test') {
+		exclude group: 'org.junit.vintage', module: 'junit-vintage-engine'
+	}
+}
+
+test {
+	useJUnitPlatform()
+}

aws/aws-rds-hello-world/docker-compose.yml

@@ -0,0 +1,18 @@
+version: '3.7'
+
+services:
+
+  postgres:
+    container_name: "rds-hello-world"
+    image: postgres
+    volumes:
+      - rds-hello-world:/var/lib/postgresql/data
+    ports:
+      - 5432:5432
+    environment:
+      - POSTGRES_USER=hello
+      - POSTGRES_PASSWORD=hello
+
+volumes:
+  rds-hello-world:
+    driver: local

aws/aws-rds-hello-world/gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,5 @@
-#Wed Apr 29 20:01:41 CEST 2020
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.3-all.zip
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-zipStorePath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.0.1-bin.zip
 zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

aws/aws-rds-hello-world/gradlew

@@ -0,0 +1,172 @@
+#!/usr/bin/env sh
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+PRG="$0"
+# Need this for relative symlinks.
+while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+        PRG="$link"
+    else
+        PRG=`dirname "$PRG"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS=""
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+    echo "$*"
+}
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+        JAVACMD="$JAVA_HOME/bin/java"
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=$((i+1))
+    done
+    case $i in
+        (0) set -- ;;
+        (1) set -- "$args0" ;;
+        (2) set -- "$args0" "$args1" ;;
+        (3) set -- "$args0" "$args1" "$args2" ;;
+        (4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Escape application args
+save () {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
+}
+APP_ARGS=$(save "$@")
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+# by default we should be in the correct project dir, but when run from Finder on Mac, the cwd is wrong
+if [ "$(uname)" = "Darwin" ] && [ "$HOME" = "$PWD" ]; then
+  cd "$(dirname "$0")"
+fi
+
+exec "$JAVACMD" "$@"

aws/aws-rds-hello-world/gradlew.bat

@@ -0,0 +1,84 @@
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS=
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

aws/aws-rds-hello-world/settings.gradle

@@ -0,0 +1 @@
+rootProject.name = 'aws-rds-hello-world'

aws/aws-rds-hello-world/src/main/java/io/reflectoring/awshelloworld/AwsHelloWorldApplication.java

@@ -0,0 +1,13 @@
+package io.reflectoring.awshelloworld;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class AwsHelloWorldApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(AwsHelloWorldApplication.class, args);
+	}
+
+}

aws/aws-rds-hello-world/src/main/java/io/reflectoring/awshelloworld/HelloWorldController.java

@@ -0,0 +1,23 @@
+package io.reflectoring.awshelloworld;
+
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+class HelloWorldController {
+
+  private final UserRepository userRepository;
+
+  HelloWorldController(UserRepository userRepository) {
+    this.userRepository = userRepository;
+  }
+
+  @GetMapping("/hello")
+  String helloWorld(){
+
+    Iterable<User> users = userRepository.findAll();
+
+    return "Hello AWS! Successfully connected to the database!";
+  }
+
+}

aws/aws-rds-hello-world/src/main/java/io/reflectoring/awshelloworld/User.java

@@ -0,0 +1,38 @@
+package io.reflectoring.awshelloworld;
+
+import org.springframework.data.annotation.Id;
+import org.springframework.data.relational.core.mapping.Table;
+
+@Table("hello_user")
+public class User {
+
+    @Id
+    private Long id;
+
+    private String name;
+
+    public User(Long id, String name) {
+        this.id = id;
+        this.name = name;
+    }
+
+    public User() {
+
+    }
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+}

aws/aws-rds-hello-world/src/main/java/io/reflectoring/awshelloworld/UserRepository.java

@@ -0,0 +1,6 @@
+package io.reflectoring.awshelloworld;
+
+import org.springframework.data.repository.CrudRepository;
+
+public interface UserRepository extends CrudRepository<User, Long> {
+}

aws/aws-rds-hello-world/src/main/resources/application.yml

@@ -0,0 +1,5 @@
+spring:
+  datasource:
+    url: jdbc:postgresql://localhost:5432/hello
+    username: hello
+    password: hello

aws/aws-rds-hello-world/src/main/resources/db/migration/V001__create_table_user.sql

@@ -0,0 +1,5 @@
+create table hello_user (
+    id varchar(36) not null unique,
+    name varchar(100) not null,
+    primary key(id)
+);

aws/cloudformation/ecs-in-two-public-subnets/README.md

@@ -0,0 +1,8 @@
+# Overview
+
+![ECS in two public subnets](ecs-in-two-public-subnets.svg)
+
+# Companion Blog Post
+
+[The AWS Journey Part 2: Deploying a Docker image from the Command Line with CloudFormation](https://reflectoring.io/aws-cloudformation-deploy-docker-image/)
+

aws/cloudformation/ecs-in-two-public-subnets/ecs-in-two-public-subnets.drawio

@@ -0,0 +1 @@
+<mxfile modified="2020-04-30T21:28:18.347Z" host="app.diagrams.net" agent="5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.149 Safari/537.36" etag="X9Eef2gSXNvxkCnmY-_0" version="13.0.4" type="device"><diagram id="Ht1M8jgEwFfnCIfOTk4-" name="Page-1">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</diagram></mxfile>

aws/cloudformation/ecs-in-two-public-subnets/network.yml

@@ -0,0 +1,247 @@
+AWSTemplateFormatVersion: '2010-09-09'
+Description: A network stack for deploying containers in AWS ECS.
+  This stack creates a VPC with two public subnets and a loadbalancer to balance traffic between those subnets.
+  Derived from a template at https://github.com/nathanpeck/aws-cloudformation-fargate.
+Resources:
+
+  VPC:
+    Type: AWS::EC2::VPC
+    Properties:
+      CidrBlock: '10.0.0.0/16'
+
+  PublicSubnetOne:
+    Type: AWS::EC2::Subnet
+    Properties:
+      AvailabilityZone:
+        Fn::Select:
+          - 0
+          - Fn::GetAZs: {Ref: 'AWS::Region'}
+      VpcId: !Ref 'VPC'
+      CidrBlock: '10.0.1.0/24'
+      MapPublicIpOnLaunch: true
+
+  PublicSubnetTwo:
+    Type: AWS::EC2::Subnet
+    Properties:
+      AvailabilityZone:
+        Fn::Select:
+          - 1
+          - Fn::GetAZs: {Ref: 'AWS::Region'}
+      VpcId: !Ref 'VPC'
+      CidrBlock: '10.0.2.0/24'
+      MapPublicIpOnLaunch: true
+
+  InternetGateway:
+    Type: AWS::EC2::InternetGateway
+
+  GatewayAttachement:
+    Type: AWS::EC2::VPCGatewayAttachment
+    Properties:
+      VpcId: !Ref 'VPC'
+      InternetGatewayId: !Ref 'InternetGateway'
+
+  PublicRouteTable:
+    Type: AWS::EC2::RouteTable
+    Properties:
+      VpcId: !Ref 'VPC'
+
+  PublicSubnetOneRouteTableAssociation:
+    Type: AWS::EC2::SubnetRouteTableAssociation
+    Properties:
+      SubnetId: !Ref PublicSubnetOne
+      RouteTableId: !Ref PublicRouteTable
+
+  PublicSubnetTwoRouteTableAssociation:
+    Type: AWS::EC2::SubnetRouteTableAssociation
+    Properties:
+      SubnetId: !Ref PublicSubnetTwo
+      RouteTableId: !Ref PublicRouteTable
+
+  PublicRoute:
+    Type: AWS::EC2::Route
+    DependsOn: GatewayAttachement
+    Properties:
+      RouteTableId: !Ref 'PublicRouteTable'
+      DestinationCidrBlock: '0.0.0.0/0'
+      GatewayId: !Ref 'InternetGateway'
+
+  PublicLoadBalancerSecurityGroup:
+    Type: AWS::EC2::SecurityGroup
+    Properties:
+      GroupDescription: Access to the public facing load balancer
+      VpcId: !Ref 'VPC'
+      SecurityGroupIngress:
+        # Allow access to ALB from anywhere on the internet
+        - CidrIp: 0.0.0.0/0
+          IpProtocol: -1
+
+  PublicLoadBalancer:
+    Type: AWS::ElasticLoadBalancingV2::LoadBalancer
+    Properties:
+      Scheme: internet-facing
+      Subnets:
+        # The load balancer is placed into the public subnets, so that traffic
+        # from the internet can reach the load balancer directly via the internet gateway
+        - !Ref PublicSubnetOne
+        - !Ref PublicSubnetTwo
+      SecurityGroups: [!Ref 'PublicLoadBalancerSecurityGroup']
+
+  DummyTargetGroupPublic:
+    Type: AWS::ElasticLoadBalancingV2::TargetGroup
+    Properties:
+      HealthCheckIntervalSeconds: 6
+      HealthCheckPath: /
+      HealthCheckProtocol: HTTP
+      HealthCheckTimeoutSeconds: 5
+      HealthyThresholdCount: 2
+      Name: "no-op"
+      Port: 80
+      Protocol: HTTP
+      UnhealthyThresholdCount: 2
+      VpcId: !Ref 'VPC'
+
+  PublicLoadBalancerListener:
+    Type: AWS::ElasticLoadBalancingV2::Listener
+    DependsOn:
+      - PublicLoadBalancer
+    Properties:
+      DefaultActions:
+        - TargetGroupArn: !Ref 'DummyTargetGroupPublic'
+          Type: 'forward'
+      LoadBalancerArn: !Ref 'PublicLoadBalancer'
+      Port: 80
+      Protocol: HTTP
+
+  ECSCluster:
+    Type: AWS::ECS::Cluster
+
+  ECSSecurityGroup:
+    Type: AWS::EC2::SecurityGroup
+    Properties:
+      GroupDescription: Access to the ECS containers
+      VpcId: !Ref 'VPC'
+
+  ECSSecurityGroupIngressFromPublicALB:
+    Type: AWS::EC2::SecurityGroupIngress
+    Properties:
+      Description: Ingress from the public ALB
+      GroupId: !Ref 'ECSSecurityGroup'
+      IpProtocol: -1
+      SourceSecurityGroupId: !Ref 'PublicLoadBalancerSecurityGroup'
+
+  ECSSecurityGroupIngressFromSelf:
+    Type: AWS::EC2::SecurityGroupIngress
+    Properties:
+      Description: Ingress from other containers in the same security group
+      GroupId: !Ref 'ECSSecurityGroup'
+      IpProtocol: -1
+      SourceSecurityGroupId: !Ref 'ECSSecurityGroup'
+
+  ECSRole:
+    Type: AWS::IAM::Role
+    Properties:
+      AssumeRolePolicyDocument:
+        Statement:
+          - Effect: Allow
+            Principal:
+              Service: [ecs.amazonaws.com]
+            Action: ['sts:AssumeRole']
+      Path: /
+      Policies:
+        - PolicyName: ecs-service
+          PolicyDocument:
+            Statement:
+              - Effect: Allow
+                Action:
+                  # Rules which allow ECS to attach network interfaces to instances
+                  # on your behalf in order for awsvpc networking mode to work right
+                  - 'ec2:AttachNetworkInterface'
+                  - 'ec2:CreateNetworkInterface'
+                  - 'ec2:CreateNetworkInterfacePermission'
+                  - 'ec2:DeleteNetworkInterface'
+                  - 'ec2:DeleteNetworkInterfacePermission'
+                  - 'ec2:Describe*'
+                  - 'ec2:DetachNetworkInterface'
+
+                  # Rules which allow ECS to update load balancers on your behalf
+                  # with the information sabout how to send traffic to your containers
+                  - 'elasticloadbalancing:DeregisterInstancesFromLoadBalancer'
+                  - 'elasticloadbalancing:DeregisterTargets'
+                  - 'elasticloadbalancing:Describe*'
+                  - 'elasticloadbalancing:RegisterInstancesWithLoadBalancer'
+                  - 'elasticloadbalancing:RegisterTargets'
+                Resource: '*'
+
+  ECSTaskExecutionRole:
+    Type: AWS::IAM::Role
+    Properties:
+      AssumeRolePolicyDocument:
+        Statement:
+          - Effect: Allow
+            Principal:
+              Service: [ecs-tasks.amazonaws.com]
+            Action: ['sts:AssumeRole']
+      Path: /
+      Policies:
+        - PolicyName: AmazonECSTaskExecutionRolePolicy
+          PolicyDocument:
+            Statement:
+              - Effect: Allow
+                Action:
+                  # Allow the ECS Tasks to download images from ECR
+                  - 'ecr:GetAuthorizationToken'
+                  - 'ecr:BatchCheckLayerAvailability'
+                  - 'ecr:GetDownloadUrlForLayer'
+                  - 'ecr:BatchGetImage'
+
+                  # Allow the ECS tasks to upload logs to CloudWatch
+                  - 'logs:CreateLogStream'
+                  - 'logs:PutLogEvents'
+                Resource: '*'
+
+Outputs:
+  ClusterName:
+    Description: The name of the ECS cluster
+    Value: !Ref 'ECSCluster'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'ClusterName' ] ]
+  ExternalUrl:
+    Description: The url of the external load balancer
+    Value: !Join ['', ['http://', !GetAtt 'PublicLoadBalancer.DNSName']]
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'ExternalUrl' ] ]
+  ECSRole:
+    Description: The ARN of the ECS role
+    Value: !GetAtt 'ECSRole.Arn'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'ECSRole' ] ]
+  ECSTaskExecutionRole:
+    Description: The ARN of the ECS role
+    Value: !GetAtt 'ECSTaskExecutionRole.Arn'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'ECSTaskExecutionRole' ] ]
+  PublicListener:
+    Description: The ARN of the public load balancer's Listener
+    Value: !Ref PublicLoadBalancerListener
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'PublicListener' ] ]
+  VPCId:
+    Description: The ID of the VPC that this stack is deployed in
+    Value: !Ref 'VPC'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'VPCId' ] ]
+  PublicSubnetOne:
+    Description: Public subnet one
+    Value: !Ref 'PublicSubnetOne'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'PublicSubnetOne' ] ]
+  PublicSubnetTwo:
+    Description: Public subnet two
+    Value: !Ref 'PublicSubnetTwo'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'PublicSubnetTwo' ] ]
+  ECSSecurityGroup:
+    Description: A security group used to allow ECS containers to receive traffic
+    Value: !Ref 'ECSSecurityGroup'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'ECSSecurityGroup' ] ]

aws/cloudformation/ecs-in-two-public-subnets/service.yml

@@ -0,0 +1,139 @@
+AWSTemplateFormatVersion: '2010-09-09'
+Description: Deploy a service on AWS Fargate, hosted in two public subnets and accessible via a public load balancer.
+  Derived from a template at https://github.com/nathanpeck/aws-cloudformation-fargate.
+Parameters:
+  StackName:
+    Type: String
+    Description: The name of the networking stack that
+      these resources are put into.
+  ServiceName:
+    Type: String
+    Description: A human-readable name for the service.
+  HealthCheckPath:
+    Type: String
+    Default: /health
+    Description: Path to perform the healthcheck on each instance.
+  HealthCheckIntervalSeconds:
+    Type: Number
+    Default: 5
+    Description: Number of seconds to wait between each health check.
+  ImageUrl:
+    Type: String
+    Description: The url of a docker image that will handle incoming traffic.
+  ContainerPort:
+    Type: Number
+    Default: 80
+    Description: The port number the application inside the docker container
+      is binding to.
+  ContainerCpu:
+    Type: Number
+    Default: 256
+    Description: How much CPU to give the container. 1024 is 1 CPU.
+  ContainerMemory:
+    Type: Number
+    Default: 512
+    Description: How much memory in megabytes to give the container.
+  Path:
+    Type: String
+    Default: "*"
+    Description: A path on the public load balancer that this service
+      should be connected to.
+  DesiredCount:
+    Type: Number
+    Default: 2
+    Description: How many copies of the service task to run.
+
+Resources:
+
+  TargetGroup:
+    Type: AWS::ElasticLoadBalancingV2::TargetGroup
+    Properties:
+      HealthCheckIntervalSeconds: !Ref 'HealthCheckIntervalSeconds'
+      HealthCheckPath: !Ref 'HealthCheckPath'
+      HealthCheckProtocol: HTTP
+      HealthCheckTimeoutSeconds: 5
+      HealthyThresholdCount: 2
+      TargetType: ip
+      Name: !Ref 'ServiceName'
+      Port: !Ref 'ContainerPort'
+      Protocol: HTTP
+      UnhealthyThresholdCount: 2
+      VpcId:
+        Fn::ImportValue:
+          !Join [':', [!Ref 'StackName', 'VPCId']]
+
+  LoadBalancerRule:
+    Type: AWS::ElasticLoadBalancingV2::ListenerRule
+    Properties:
+      Actions:
+        - TargetGroupArn: !Ref 'TargetGroup'
+          Type: 'forward'
+      Conditions:
+        - Field: path-pattern
+          Values: [!Ref 'Path']
+      ListenerArn:
+        Fn::ImportValue:
+          !Join [':', [!Ref 'StackName', 'PublicListener']]
+      Priority: 1
+
+  LogGroup:
+    Type: AWS::Logs::LogGroup
+    Properties:
+      LogGroupName: !Ref 'ServiceName'
+      RetentionInDays: 1
+
+  TaskDefinition:
+    Type: AWS::ECS::TaskDefinition
+    Properties:
+      Family: !Ref 'ServiceName'
+      Cpu: !Ref 'ContainerCpu'
+      Memory: !Ref 'ContainerMemory'
+      NetworkMode: awsvpc
+      RequiresCompatibilities:
+        - FARGATE
+      ExecutionRoleArn:
+        Fn::ImportValue:
+          !Join [':', [!Ref 'StackName', 'ECSTaskExecutionRole']]
+      ContainerDefinitions:
+        - Name: !Ref 'ServiceName'
+          Cpu: !Ref 'ContainerCpu'
+          Memory: !Ref 'ContainerMemory'
+          Image: !Ref 'ImageUrl'
+          PortMappings:
+            - ContainerPort: !Ref 'ContainerPort'
+          LogConfiguration:
+            LogDriver: 'awslogs'
+            Options:
+              awslogs-group: !Ref 'ServiceName'
+              awslogs-region: !Ref AWS::Region
+              awslogs-stream-prefix: !Ref 'ServiceName'
+
+  Service:
+    Type: AWS::ECS::Service
+    DependsOn: LoadBalancerRule
+    Properties:
+      ServiceName: !Ref 'ServiceName'
+      Cluster:
+        Fn::ImportValue:
+          !Join [':', [!Ref 'StackName', 'ClusterName']]
+      LaunchType: FARGATE
+      DeploymentConfiguration:
+        MaximumPercent: 200
+        MinimumHealthyPercent: 50
+      DesiredCount: !Ref 'DesiredCount'
+      NetworkConfiguration:
+        AwsvpcConfiguration:
+          AssignPublicIp: ENABLED
+          SecurityGroups:
+            - Fn::ImportValue:
+                !Join [':', [!Ref 'StackName', 'ECSSecurityGroup']]
+          Subnets:
+            - Fn::ImportValue:
+                !Join [':', [!Ref 'StackName', 'PublicSubnetOne']]
+            - Fn::ImportValue:
+                !Join [':', [!Ref 'StackName', 'PublicSubnetTwo']]
+      TaskDefinition: !Ref 'TaskDefinition'
+      LoadBalancers:
+        - ContainerName: !Ref 'ServiceName'
+          ContainerPort: !Ref 'ContainerPort'
+          TargetGroupArn: !Ref 'TargetGroup'

aws/cloudformation/rds-in-private-subnet/README.md

@@ -0,0 +1,7 @@
+# Overview
+
+![RDS in private subnet](rds-in-private-subnet.svg)
+
+# Companion Blog Post
+
+TO DO

aws/cloudformation/rds-in-private-subnet/database.yml

@@ -0,0 +1,88 @@
+AWSTemplateFormatVersion: '2010-09-09'
+Description: A stack that creates an RDS instance and places it into two subnets
+Parameters:
+  NetworkStackName:
+    Type: String
+    Description: The name of the networking stack that this stack will build upon.
+  DBInstanceClass:
+    Type: String
+    Description: The ID of the second subnet to place the RDS instance into.
+    Default: 'db.t2.micro'
+  DBName:
+    Type: String
+    Description: The name of the database that is created within the PostgreSQL instance.
+  DBUsername:
+    Type: String
+    Description: The master user name for the PostgreSQL instance.
+Resources:
+
+  Secret:
+    Type: "AWS::SecretsManager::Secret"
+    Properties:
+      Name: !Ref 'DBUsername'
+      GenerateSecretString:
+        # This will generate a JSON object with the keys "username" and password.
+        SecretStringTemplate: !Join ['', ['{"username": "', !Ref 'DBUsername' ,'"}']]
+        GenerateStringKey: "password"
+        PasswordLength: 32
+        ExcludeCharacters: '"@/\'
+
+  DBSubnetGroup:
+    Type: AWS::RDS::DBSubnetGroup
+    Properties:
+      DBSubnetGroupDescription: Subnet group for the RDS instance
+      DBSubnetGroupName: DBSubnetGroup
+      SubnetIds:
+        - Fn::ImportValue:
+            !Join [':', [!Ref 'NetworkStackName', 'PrivateSubnetOne']]
+        - Fn::ImportValue:
+            !Join [':', [!Ref 'NetworkStackName', 'PrivateSubnetTwo']]
+
+  PostgresInstance:
+    Type: AWS::RDS::DBInstance
+    Properties:
+      AllocatedStorage: 20
+      AvailabilityZone:
+        Fn::Select:
+          - 0
+          - Fn::GetAZs: {Ref: 'AWS::Region'}
+      DBInstanceClass: !Ref 'DBInstanceClass'
+      DBName: !Ref 'DBName'
+      DBSubnetGroupName: !Ref 'DBSubnetGroup'
+      Engine: postgres
+      EngineVersion: 11.5
+      MasterUsername: !Ref 'DBUsername'
+      MasterUserPassword: !Join ['', ['{{resolve:secretsmanager:', !Ref Secret, ':SecretString:password}}' ]]
+      PubliclyAccessible: false
+      VPCSecurityGroups:
+        - Fn::ImportValue:
+            !Join [':', [!Ref 'NetworkStackName', 'DBSecurityGroupId']]
+
+  SecretRDSInstanceAttachment:
+    Type: "AWS::SecretsManager::SecretTargetAttachment"
+    Properties:
+      SecretId: !Ref Secret
+      TargetId: !Ref PostgresInstance
+      TargetType: AWS::RDS::DBInstance
+
+Outputs:
+  EndpointAddress:
+    Description: Address of the RDS endpoint.
+    Value: !GetAtt 'PostgresInstance.Endpoint.Address'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'EndpointAddress' ] ]
+  EndpointPort:
+    Description: Port of the RDS endpoint.
+    Value: !GetAtt 'PostgresInstance.Endpoint.Port'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'EndpointPort' ] ]
+  DBName:
+    Description: The name of the database that is created within the PostgreSQL instance.
+    Value: !Ref DBName
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'DBName' ] ]
+  Secret:
+    Description: Reference to the secret containing the password to the database.
+    Value: !Ref 'Secret'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'Secret' ] ]

aws/cloudformation/rds-in-private-subnet/network.yml

@@ -0,0 +1,298 @@
+AWSTemplateFormatVersion: '2010-09-09'
+Description: A network stack for deploying containers in AWS ECS.
+  This stack creates a VPC with two public subnets and a loadbalancer to balance traffic between those subnets.
+  Derived from a template at https://github.com/nathanpeck/aws-cloudformation-fargate.
+Resources:
+
+  VPC:
+    Type: AWS::EC2::VPC
+    Properties:
+      CidrBlock: '10.0.0.0/16'
+
+  PublicSubnetOne:
+    Type: AWS::EC2::Subnet
+    Properties:
+      AvailabilityZone:
+        Fn::Select:
+          - 0
+          - Fn::GetAZs: {Ref: 'AWS::Region'}
+      VpcId: !Ref 'VPC'
+      CidrBlock: '10.0.1.0/24'
+      MapPublicIpOnLaunch: true
+
+  PublicSubnetTwo:
+    Type: AWS::EC2::Subnet
+    Properties:
+      AvailabilityZone:
+        Fn::Select:
+          - 1
+          - Fn::GetAZs: {Ref: 'AWS::Region'}
+      VpcId: !Ref 'VPC'
+      CidrBlock: '10.0.2.0/24'
+      MapPublicIpOnLaunch: true
+
+  InternetGateway:
+    Type: AWS::EC2::InternetGateway
+
+  GatewayAttachement:
+    Type: AWS::EC2::VPCGatewayAttachment
+    Properties:
+      VpcId: !Ref 'VPC'
+      InternetGatewayId: !Ref 'InternetGateway'
+
+  PublicRouteTable:
+    Type: AWS::EC2::RouteTable
+    Properties:
+      VpcId: !Ref 'VPC'
+
+  PublicSubnetOneRouteTableAssociation:
+    Type: AWS::EC2::SubnetRouteTableAssociation
+    Properties:
+      SubnetId: !Ref PublicSubnetOne
+      RouteTableId: !Ref PublicRouteTable
+
+  PublicSubnetTwoRouteTableAssociation:
+    Type: AWS::EC2::SubnetRouteTableAssociation
+    Properties:
+      SubnetId: !Ref PublicSubnetTwo
+      RouteTableId: !Ref PublicRouteTable
+
+  PublicRoute:
+    Type: AWS::EC2::Route
+    DependsOn: GatewayAttachement
+    Properties:
+      RouteTableId: !Ref 'PublicRouteTable'
+      DestinationCidrBlock: '0.0.0.0/0'
+      GatewayId: !Ref 'InternetGateway'
+
+  PublicLoadBalancerSecurityGroup:
+    Type: AWS::EC2::SecurityGroup
+    Properties:
+      GroupDescription: Access to the public facing load balancer
+      VpcId: !Ref 'VPC'
+      SecurityGroupIngress:
+        # Allow access to ALB from anywhere on the internet
+        - CidrIp: 0.0.0.0/0
+          IpProtocol: -1
+
+  PublicLoadBalancer:
+    Type: AWS::ElasticLoadBalancingV2::LoadBalancer
+    Properties:
+      Scheme: internet-facing
+      Subnets:
+        # The load balancer is placed into the public subnets, so that traffic
+        # from the internet can reach the load balancer directly via the internet gateway
+        - !Ref PublicSubnetOne
+        - !Ref PublicSubnetTwo
+      SecurityGroups: [!Ref 'PublicLoadBalancerSecurityGroup']
+
+  DummyTargetGroupPublic:
+    Type: AWS::ElasticLoadBalancingV2::TargetGroup
+    Properties:
+      HealthCheckIntervalSeconds: 6
+      HealthCheckPath: /
+      HealthCheckProtocol: HTTP
+      HealthCheckTimeoutSeconds: 5
+      HealthyThresholdCount: 2
+      Name: "no-op"
+      Port: 80
+      Protocol: HTTP
+      UnhealthyThresholdCount: 2
+      VpcId: !Ref 'VPC'
+
+  PublicLoadBalancerListener:
+    Type: AWS::ElasticLoadBalancingV2::Listener
+    DependsOn:
+      - PublicLoadBalancer
+    Properties:
+      DefaultActions:
+        - TargetGroupArn: !Ref 'DummyTargetGroupPublic'
+          Type: 'forward'
+      LoadBalancerArn: !Ref 'PublicLoadBalancer'
+      Port: 80
+      Protocol: HTTP
+
+  ECSCluster:
+    Type: AWS::ECS::Cluster
+
+  ECSSecurityGroup:
+    Type: AWS::EC2::SecurityGroup
+    Properties:
+      GroupDescription: Access to the ECS containers
+      VpcId: !Ref 'VPC'
+
+  ECSSecurityGroupIngressFromPublicALB:
+    Type: AWS::EC2::SecurityGroupIngress
+    Properties:
+      Description: Ingress from the public ALB
+      GroupId: !Ref 'ECSSecurityGroup'
+      IpProtocol: -1
+      SourceSecurityGroupId: !Ref 'PublicLoadBalancerSecurityGroup'
+
+  ECSSecurityGroupIngressFromSelf:
+    Type: AWS::EC2::SecurityGroupIngress
+    Properties:
+      Description: Ingress from other containers in the same security group
+      GroupId: !Ref 'ECSSecurityGroup'
+      IpProtocol: -1
+      SourceSecurityGroupId: !Ref 'ECSSecurityGroup'
+
+  ECSRole:
+    Type: AWS::IAM::Role
+    Properties:
+      AssumeRolePolicyDocument:
+        Statement:
+          - Effect: Allow
+            Principal:
+              Service: [ecs.amazonaws.com]
+            Action: ['sts:AssumeRole']
+      Path: /
+      Policies:
+        - PolicyName: ecs-service
+          PolicyDocument:
+            Statement:
+              - Effect: Allow
+                Action:
+                  # Rules which allow ECS to attach network interfaces to instances
+                  # on your behalf in order for awsvpc networking mode to work right
+                  - 'ec2:AttachNetworkInterface'
+                  - 'ec2:CreateNetworkInterface'
+                  - 'ec2:CreateNetworkInterfacePermission'
+                  - 'ec2:DeleteNetworkInterface'
+                  - 'ec2:DeleteNetworkInterfacePermission'
+                  - 'ec2:Describe*'
+                  - 'ec2:DetachNetworkInterface'
+
+                  # Rules which allow ECS to update load balancers on your behalf
+                  # with the information sabout how to send traffic to your containers
+                  - 'elasticloadbalancing:DeregisterInstancesFromLoadBalancer'
+                  - 'elasticloadbalancing:DeregisterTargets'
+                  - 'elasticloadbalancing:Describe*'
+                  - 'elasticloadbalancing:RegisterInstancesWithLoadBalancer'
+                  - 'elasticloadbalancing:RegisterTargets'
+                Resource: '*'
+
+  ECSTaskExecutionRole:
+    Type: AWS::IAM::Role
+    Properties:
+      AssumeRolePolicyDocument:
+        Statement:
+          - Effect: Allow
+            Principal:
+              Service: [ecs-tasks.amazonaws.com]
+            Action: ['sts:AssumeRole']
+      Path: /
+      Policies:
+        - PolicyName: AmazonECSTaskExecutionRolePolicy
+          PolicyDocument:
+            Statement:
+              - Effect: Allow
+                Action:
+                  # Allow the ECS Tasks to download images from ECR
+                  - 'ecr:GetAuthorizationToken'
+                  - 'ecr:BatchCheckLayerAvailability'
+                  - 'ecr:GetDownloadUrlForLayer'
+                  - 'ecr:BatchGetImage'
+
+                  # Allow the ECS tasks to upload logs to CloudWatch
+                  - 'logs:CreateLogStream'
+                  - 'logs:PutLogEvents'
+                Resource: '*'
+
+  PrivateSubnetOne:
+    Type: AWS::EC2::Subnet
+    Properties:
+      AvailabilityZone:
+        Fn::Select:
+          - 0
+          - Fn::GetAZs: {Ref: 'AWS::Region'}
+      VpcId: !Ref 'VPC'
+      CidrBlock: '10.0.101.0/24'
+      MapPublicIpOnLaunch: false
+
+  PrivateSubnetTwo:
+    Type: AWS::EC2::Subnet
+    Properties:
+      AvailabilityZone:
+        Fn::Select:
+          - 1
+          - Fn::GetAZs: {Ref: 'AWS::Region'}
+      VpcId: !Ref 'VPC'
+      CidrBlock: '10.0.102.0/24'
+      MapPublicIpOnLaunch: false
+
+  DBSecurityGroup:
+    Type: AWS::EC2::SecurityGroup
+    Properties:
+      GroupDescription: Access to the RDS instance
+      VpcId: !Ref 'VPC'
+
+  DBSecurityGroupIngressFromECS:
+    Type: AWS::EC2::SecurityGroupIngress
+    Properties:
+      Description: Ingress from the ECS containers to the RDS instance
+      GroupId: !Ref 'DBSecurityGroup'
+      IpProtocol: -1
+      SourceSecurityGroupId: !Ref 'ECSSecurityGroup'
+
+Outputs:
+  PrivateSubnetOne:
+    Description: Private subnet one
+    Value: !Ref 'PrivateSubnetOne'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'PrivateSubnetOne' ] ]
+  PrivateSubnetTwo:
+    Description: Private subnet two
+    Value: !Ref 'PrivateSubnetTwo'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'PrivateSubnetTwo' ] ]
+  DBSecurityGroupId:
+    Description: ID of the security group that an RDS instance can be placed into.
+    Value: !Ref 'DBSecurityGroup'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'DBSecurityGroupId' ] ]
+  ClusterName:
+    Description: The name of the ECS cluster
+    Value: !Ref 'ECSCluster'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'ClusterName' ] ]
+  ExternalUrl:
+    Description: The url of the external load balancer
+    Value: !Join ['', ['http://', !GetAtt 'PublicLoadBalancer.DNSName']]
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'ExternalUrl' ] ]
+  ECSRole:
+    Description: The ARN of the ECS role
+    Value: !GetAtt 'ECSRole.Arn'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'ECSRole' ] ]
+  ECSTaskExecutionRole:
+    Description: The ARN of the ECS role
+    Value: !GetAtt 'ECSTaskExecutionRole.Arn'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'ECSTaskExecutionRole' ] ]
+  PublicListener:
+    Description: The ARN of the public load balancer's Listener
+    Value: !Ref PublicLoadBalancerListener
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'PublicListener' ] ]
+  VPCId:
+    Description: The ID of the VPC that this stack is deployed in
+    Value: !Ref 'VPC'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'VPCId' ] ]
+  PublicSubnetOne:
+    Description: Public subnet one
+    Value: !Ref 'PublicSubnetOne'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'PublicSubnetOne' ] ]
+  PublicSubnetTwo:
+    Description: Public subnet two
+    Value: !Ref 'PublicSubnetTwo'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'PublicSubnetTwo' ] ]
+  ECSSecurityGroup:
+    Description: A security group used to allow ECS containers to receive traffic
+    Value: !Ref 'ECSSecurityGroup'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'ECSSecurityGroup' ] ]

aws/cloudformation/rds-in-private-subnet/rds-in-private-subnet.drawio

@@ -0,0 +1 @@
+<mxfile modified="2020-05-11T21:18:00.281Z" host="app.diagrams.net" agent="5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.149 Safari/537.36" etag="d22WT4Cb11cg7E6o-Mdr" version="13.0.9" type="device"><diagram id="Ht1M8jgEwFfnCIfOTk4-" name="Page-1">7VvZcuI4FP0aHpuyJK+PYUk6VemaTNHTyxNlsGI8MRYtiy1fP5KRwZbEkkBI00OKqljXspZ7z7mLDA3UHi/uaDgZfSERThvQihYN1GlACJDj8H9CslxJPM9eCWKaRLLTRtBLXrAUWlI6TSKc1zoyQlKWTOrCIckyPGQ1WUgpmde7PZG0PuskjLEm6A3DVJd+TyI2klLgBpsbn3ESj+TUPvRWN8Zh2VnuJB+FEZlXRKjbQG1KCFtdjRdtnArllXpZPXe75e56YRRn7JAHHuJp6+UXX9i3PB/cv7TDr5/+/SRHmYXpVG74cTpIk6FY73SQYSbXzpalQiYkyVihVKfFP3zOttVw+J22aDWhowjUtlcXAL0lxqgL1LZXFwB1eKDMD9QFVgRaqza8pcxvVRbIP6hFpixNMtxew8/iwpiGUcLN0iYpoVyWkYxrrzVi45S3AL+cjxKGe5NwKLQ659ThsieSMUkAAMu2VLx4hgNoIq7Hi1hwrRnOc7sZUzKdFFPecwoY7/ZzPJzShC37m849RskzlsvNi0a52AZE0PZ9YIslJGlakXeDW9R1uXyGKUs4SW7SJBaTMiKGDWUrxU9MDMu3l2TxQ9HqIEtuyTRPFOYjHMnlSEjyKfBiK9bBmkHc9WAyxowueRf5AHIk6aTXQaU7mVc47EvZqEJf4IICIYX7kK4jXg+/YRe/kAQzk22Eh3Dxcu9977wMnl37S/SrP/hUeoIK2749tq8Mu3yGzSbDg3kkl3oiCt3ctLyWb6aQxhcDq7ZSCLh1CgFLp5BrGyiEAut4/hiDla0HK5rMQoav0eoP4tL/L1o5wQdHq0U6ve3jv2af7eXPX2zwzwu+m5pSwyvbrmz7Hdh2VGBT2QbgmdlmjG2OxrYO36zVk0Sz7grzqIQz5BWawZwbt+27VUWCrVZSYaXYZD2UYs0T+EAXKlZxDFYptV9LN8AJ0g1juo6utfHV//15/k+tjc/u/4xkA57Gtm67JzwgprOEQ+G3dn3HGcQ/wPUhU6X1bq5Pj0YN6KZivwN+EYuLm8mE+8KQJZxZ5T1a3nwgYaRLue7CbIhpeYcvbT2cZl+j86hxobTjQzjA6SPJk2ItqDMgjJHxXiYOucX4Wmqux+BGUDPc7LSf8o31B+U+NCdw6/gOsrd7uROgBdp1tEDXagKkl+aBjhcPvhNc/P1wuRfKLmKmG46FGbJBPik0oqLkjpcY83B5YSBJ5P76sVy+GRvuu2Jj7SU22PhYYARbnPrXMH8+zJhqVETwVsyvKVEo2PO7VpV8nYTygVb2zggVGlCN0rGcNg89htjxVPydAU77Upswn6zU8ZQsxDrMuQ7FOZnSIV5lOi3eNOU8eJifBmk2UGKWryPNM4Qs770iFtSzdQ1gOIpxqVkBBxKTLEy7G2nVLDiLbsT7Q2HclAyfhSgdFO3SxgVsQsrKfpLI/MnbJF17Cy0psZ2WK2DKE84sWiOL24Iuf1QbP0WD59ey2VlUb3aW1dYjpgnXo4DW7jRxBZJdepSU5fuKMdvv84VOdwKmmsSUR8gUpzyczuqvWE2QkMM9irpqAz6lgIeBq+Wlq33K56ovRZWhgFJ2Il/PcVeq0MYqYLre6BHIda/IPQC5ewHpfBwgoXVCRCrVAArOj0hTPndJiHw7iIKPAxGyAhVEb0OQXX7npkSQbTWtyh84CEzcECIJX3eTZ1vblw81DuxcpdYfOAqWVys4LbL1hHRXpXKRBQh8femx/mrS5sSr/LITOlHVqhYmgZ4uBk3D8a5jH58wGl9vwf1I4NZiMcW9vx94x/uM+6dMHERdFCxolOt4gF0PFV8aeL9S1LXtmsWBZ6/DWNXoUDe5v8N1HmXySy8Rtpplb1ZvSOp3keJDwh9Qwh+0m77/tgjoAnNsOXXMc3bHsNf2PzrmGd8s6qi/nsH8LmcwR70yVc9gkGs3TXH1nY5hjGC7+Fp2kbAf5dz8ulLJ8tamkBWNZaVhLmMVP/o23+3ovns7zz/EVSPrrZWK6g8PLHTPXZvY1hn8tP4C9MKoc/pjoNfyZ1f8Oyz3OQt/7KBekEOVBE0L2bYPPcd3oeW9MQdybGVYHh38wHUc4PHQgdR3PqdKidz6bhTq7O2/L4VS64ojUyje3PwCZ9V98zsm1P0P</diagram></mxfile>

aws/cloudformation/rds-in-private-subnet/service.yml

@@ -0,0 +1,164 @@
+AWSTemplateFormatVersion: '2010-09-09'
+Description: Deploy a service on AWS Fargate, hosted in two public subnets and accessible via a public load balancer.
+  Derived from a template at https://github.com/nathanpeck/aws-cloudformation-fargate.
+Parameters:
+  NetworkStackName:
+    Type: String
+    Description: The name of the networking stack that
+      these resources are put into.
+  DatabaseStackName:
+    Type: String
+    Description: The name of the database stack with the database this service should connect to.
+  ServiceName:
+    Type: String
+    Description: A human-readable name for the service.
+  HealthCheckPath:
+    Type: String
+    Default: /health
+    Description: Path to perform the healthcheck on each instance.
+  HealthCheckIntervalSeconds:
+    Type: Number
+    Default: 5
+    Description: Number of seconds to wait between each health check.
+  ImageUrl:
+    Type: String
+    Description: The url of a docker image that will handle incoming traffic.
+  ContainerPort:
+    Type: Number
+    Default: 80
+    Description: The port number the application inside the docker container
+      is binding to.
+  ContainerCpu:
+    Type: Number
+    Default: 256
+    Description: How much CPU to give the container. 1024 is 1 CPU.
+  ContainerMemory:
+    Type: Number
+    Default: 512
+    Description: How much memory in megabytes to give the container.
+  Path:
+    Type: String
+    Default: "*"
+    Description: A path on the public load balancer that this service
+      should be connected to.
+  DesiredCount:
+    Type: Number
+    Default: 2
+    Description: How many copies of the service task to run.
+
+Resources:
+
+  TargetGroup:
+    Type: AWS::ElasticLoadBalancingV2::TargetGroup
+    Properties:
+      HealthCheckIntervalSeconds: !Ref 'HealthCheckIntervalSeconds'
+      HealthCheckPath: !Ref 'HealthCheckPath'
+      HealthCheckProtocol: HTTP
+      HealthCheckTimeoutSeconds: 5
+      HealthyThresholdCount: 2
+      TargetType: ip
+      Name: !Ref 'ServiceName'
+      Port: !Ref 'ContainerPort'
+      Protocol: HTTP
+      UnhealthyThresholdCount: 2
+      VpcId:
+        Fn::ImportValue:
+          !Join [':', [!Ref 'NetworkStackName', 'VPCId']]
+
+  LoadBalancerRule:
+    Type: AWS::ElasticLoadBalancingV2::ListenerRule
+    Properties:
+      Actions:
+        - TargetGroupArn: !Ref 'TargetGroup'
+          Type: 'forward'
+      Conditions:
+        - Field: path-pattern
+          Values: [!Ref 'Path']
+      ListenerArn:
+        Fn::ImportValue:
+          !Join [':', [!Ref 'NetworkStackName', 'PublicListener']]
+      Priority: 1
+
+  LogGroup:
+    Type: AWS::Logs::LogGroup
+    Properties:
+      LogGroupName: !Ref 'ServiceName'
+      RetentionInDays: 1
+
+  TaskDefinition:
+    Type: AWS::ECS::TaskDefinition
+    Properties:
+      Family: !Ref 'ServiceName'
+      Cpu: !Ref 'ContainerCpu'
+      Memory: !Ref 'ContainerMemory'
+      NetworkMode: awsvpc
+      RequiresCompatibilities:
+        - FARGATE
+      ExecutionRoleArn:
+        Fn::ImportValue:
+          !Join [':', [!Ref 'NetworkStackName', 'ECSTaskExecutionRole']]
+      ContainerDefinitions:
+        - Name: !Ref 'ServiceName'
+          Cpu: !Ref 'ContainerCpu'
+          Memory: !Ref 'ContainerMemory'
+          Image: !Ref 'ImageUrl'
+          Environment:
+            - Name: SPRING_DATASOURCE_URL
+              Value: !Join
+                - ''
+                - - 'jdbc:postgresql://'
+                  - Fn::ImportValue: !Join [':', [!Ref 'DatabaseStackName', 'EndpointAddress']]
+                  - ':'
+                  - Fn::ImportValue: !Join [':', [!Ref 'DatabaseStackName', 'EndpointPort']]
+                  - '/'
+                  - Fn::ImportValue: !Join [':', [!Ref 'DatabaseStackName', 'DBName']]
+            - Name: SPRING_DATASOURCE_USERNAME
+              Value: !Join
+                - ''
+                - - '{{resolve:secretsmanager:'
+                  - Fn::ImportValue: !Join [':', [!Ref 'DatabaseStackName', 'Secret']]
+                  - ':SecretString:username}}'
+            - Name: SPRING_DATASOURCE_PASSWORD
+              Value: !Join
+                - ''
+                - - '{{resolve:secretsmanager:'
+                  - Fn::ImportValue: !Join [':', [!Ref 'DatabaseStackName', 'Secret']]
+                  - ':SecretString:password}}'
+          PortMappings:
+            - ContainerPort: !Ref 'ContainerPort'
+          LogConfiguration:
+            LogDriver: 'awslogs'
+            Options:
+              awslogs-group: !Ref 'ServiceName'
+              awslogs-region: !Ref AWS::Region
+              awslogs-stream-prefix: !Ref 'ServiceName'
+
+  Service:
+    Type: AWS::ECS::Service
+    DependsOn: LoadBalancerRule
+    Properties:
+      ServiceName: !Ref 'ServiceName'
+      Cluster:
+        Fn::ImportValue:
+          !Join [':', [!Ref 'NetworkStackName', 'ClusterName']]
+      LaunchType: FARGATE
+      DeploymentConfiguration:
+        MaximumPercent: 200
+        MinimumHealthyPercent: 50
+      DesiredCount: !Ref 'DesiredCount'
+      NetworkConfiguration:
+        AwsvpcConfiguration:
+          AssignPublicIp: ENABLED
+          SecurityGroups:
+            - Fn::ImportValue:
+                !Join [':', [!Ref 'NetworkStackName', 'ECSSecurityGroup']]
+          Subnets:
+            - Fn::ImportValue:
+                !Join [':', [!Ref 'NetworkStackName', 'PublicSubnetOne']]
+            - Fn::ImportValue:
+                !Join [':', [!Ref 'NetworkStackName', 'PublicSubnetTwo']]
+      TaskDefinition: !Ref 'TaskDefinition'
+      LoadBalancers:
+        - ContainerName: !Ref 'ServiceName'
+          ContainerPort: !Ref 'ContainerPort'
+          TargetGroupArn: !Ref 'TargetGroup'

build-all.sh

@@ -10,7 +10,7 @@ build_gradle_module() {
   echo "+++"
   cd $MODULE_PATH && {
     chmod +x gradlew
-    ./gradlew clean build --info --stacktrace
+    ./gradlew clean build
     if [ $? -ne 0 ]
     then
       echo ""
@@ -28,9 +28,40 @@ build_gradle_module() {
   }
 }
 
-chmod +x gradlew
+build_maven_module() {
+  MODULE_PATH=$1
+  echo ""
+  echo "+++"
+  echo "+++ BUILDING MODULE $MODULE_PATH"
+  echo "+++"
+  cd $MODULE_PATH && {
+    chmod +x mvnw
+    ./mvnw clean package
+    if [ $? -ne 0 ]
+    then
+      echo ""
+      echo "+++"
+      echo "+++ BUILDING MODULE $MODULE_PATH FAILED"
+      echo "+++"
+      exit 1
+    else
+      echo ""
+      echo "+++"
+      echo "+++ BUILDING MODULE $MODULE_PATH SUCCESSFUL"
+      echo "+++"
+    fi
+    cd $MAIN_DIR
+  }
+}
 
-build_gradle_module "spring-boot/spring-boot-springdoc"
+build_maven_module "spring-boot/dependency-injection"
+build_maven_module "spring-boot/spring-boot-openapi"
+build_maven_module "spring-boot/data-migration/liquibase"
+build_gradle_module "spring-boot/boundaries"
+build_gradle_module "spring-boot/argumentresolver"
+build_gradle_module "spring-data/spring-data-jdbc-converter"
+build_gradle_module "solid"
+build_gradle_module "spring-boot/data-migration/flyway"
 build_gradle_module "reactive"
 build_gradle_module "junit/assumptions"
 build_gradle_module "logging"
@@ -53,6 +84,8 @@ build_gradle_module "spring-boot/startup"
 build_gradle_module "spring-boot/static"
 build_gradle_module "spring-boot/validation"
 build_gradle_module "spring-boot/profiles"
+build_gradle_module "spring-boot/password-encoding"
+build_gradle_module "spring-boot/testcontainers"
 build_gradle_module "spring-cloud/feign-with-spring-data-rest"
 build_gradle_module "spring-cloud/sleuth-downstream-service"
 build_gradle_module "spring-cloud/sleuth-upstream-service"
@@ -65,4 +98,4 @@ build_gradle_module "tools/jacoco"
 echo ""
 echo "+++"
 echo "+++ ALL MODULES SUCCESSFUL"
-echo "+++"
+echo "+++"

solid/build.gradle

@@ -0,0 +1,25 @@
+buildscript {
+	repositories {
+		jcenter()
+	}
+}
+
+apply plugin: 'java'
+apply plugin: 'java-library'
+
+version = '0.0.1-SNAPSHOT'
+sourceCompatibility = 8
+
+repositories {
+	mavenLocal()
+	mavenCentral()
+}
+
+dependencies {
+	testImplementation 'org.junit.jupiter:junit-jupiter-engine:5.0.1'
+	testImplementation 'org.assertj:assertj-core:2.6.0'
+}
+
+test {
+	useJUnitPlatform()
+}

solid/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.10.1-bin.zip

solid/gradlew

@@ -0,0 +1,172 @@
+#!/usr/bin/env sh
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+PRG="$0"
+# Need this for relative symlinks.
+while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+        PRG="$link"
+    else
+        PRG=`dirname "$PRG"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS=""
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+    echo "$*"
+}
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+        JAVACMD="$JAVA_HOME/bin/java"
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=$((i+1))
+    done
+    case $i in
+        (0) set -- ;;
+        (1) set -- "$args0" ;;
+        (2) set -- "$args0" "$args1" ;;
+        (3) set -- "$args0" "$args1" "$args2" ;;
+        (4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Escape application args
+save () {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
+}
+APP_ARGS=$(save "$@")
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+# by default we should be in the correct project dir, but when run from Finder on Mac, the cwd is wrong
+if [ "$(uname)" = "Darwin" ] && [ "$HOME" = "$PWD" ]; then
+  cd "$(dirname "$0")"
+fi
+
+exec "$JAVACMD" "$@"

solid/gradlew.bat

@@ -0,0 +1,84 @@
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS=
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

solid/src/main/java/io/reflectoring/solid/isp/AdaptedBurgerOrder.java

@@ -0,0 +1,13 @@
+package io.reflectoring.solid.isp;
+
+class AdaptedBurgerOrder implements IAdapterOrderForBurger {
+    private final IOrder burgerOrder;
+    public AdaptedBurgerOrder(IOrder burgerOrder){
+        this.burgerOrder = burgerOrder;
+    }
+    @Override
+    public void orderBurger(int quantity) {
+        burgerOrder.orderBurger(quantity);
+    }
+}
+

solid/src/main/java/io/reflectoring/solid/isp/AdaptedFriesOrder.java

@@ -0,0 +1,13 @@
+package io.reflectoring.solid.isp;
+
+class AdaptedFriesOrder implements IAdapterOrderForFries {
+    private final IOrder friesOrder;
+    public AdaptedFriesOrder(IOrder friesOrder){
+        this.friesOrder = friesOrder;
+    }
+
+    @Override
+    public void orderFries(int quantity) {
+        friesOrder.orderFries(quantity);
+    }
+}

solid/src/main/java/io/reflectoring/solid/isp/BetterOrderService.java

@@ -0,0 +1,5 @@
+package io.reflectoring.solid.isp;
+
+interface BetterOrderService {
+    void submitOrder(Order order);
+}

solid/src/main/java/io/reflectoring/solid/isp/BurgerOrder.java

@@ -0,0 +1,13 @@
+package io.reflectoring.solid.isp;
+
+class BurgerOrder implements IOrder {
+    @Override
+    public void orderBurger(int quantity) {
+
+    }
+
+    @Override
+    public void orderFries(int fries) {
+        throw new UnsupportedOperationException("No fries in Burger only order");
+    }
+}

solid/src/main/java/io/reflectoring/solid/isp/BurgerOrderService.java

@@ -0,0 +1,18 @@
+package io.reflectoring.solid.isp;
+
+class BurgerOrderService implements OrderService {
+    @Override
+    public void orderBurger(int quantity) {
+        System.out.println("Received order of "+quantity+" burgers");
+    }
+
+    @Override
+    public void orderFries(int fries) {
+        throw new UnsupportedOperationException("No fries in burger only order");
+    }
+
+    @Override
+    public void orderCombo(int quantity, int fries) {
+        throw new UnsupportedOperationException("No combo in burger only order");
+    }
+}

solid/src/main/java/io/reflectoring/solid/isp/ComboOrderService.java

@@ -0,0 +1,18 @@
+package io.reflectoring.solid.isp;
+
+class ComboOrderService implements OrderService{
+    @Override
+    public void orderBurger(int quantity) {
+        System.out.println("Received order of "+quantity+" burgers");
+    }
+
+    @Override
+    public void orderFries(int fries) {
+        System.out.println("Received order of "+fries+ " fries");
+    }
+
+    @Override
+    public void orderCombo(int quantity, int fries) {
+        System.out.println("Received order of "+quantity+" burgers and "+ fries+" fries");
+    }
+}

solid/src/main/java/io/reflectoring/solid/isp/FriesOrderService.java

@@ -0,0 +1,19 @@
+package io.reflectoring.solid.isp;
+
+class FriesOrderService implements OrderService {
+    @Override
+    public void orderBurger(int quantity) {
+        throw new UnsupportedOperationException("No burger in fries only order");
+    }
+
+    @Override
+    public void orderFries(int fries) {
+        System.out.println("Received order of "+fries+ " fries");
+    }
+
+    @Override
+    public void orderCombo(int quantity, int fries) {
+        throw new UnsupportedOperationException("No combo in fries only order");
+    }
+}
+

solid/src/main/java/io/reflectoring/solid/isp/IAdapterOrderForBurger.java

@@ -0,0 +1,5 @@
+package io.reflectoring.solid.isp;
+
+interface IAdapterOrderForBurger {
+    void orderBurger(int quantity);
+}

solid/src/main/java/io/reflectoring/solid/isp/IAdapterOrderForFries.java

@@ -0,0 +1,5 @@
+package io.reflectoring.solid.isp;
+
+interface IAdapterOrderForFries {
+    void orderFries(int quantity);
+}

solid/src/main/java/io/reflectoring/solid/isp/IBurgerOrder.java

@@ -0,0 +1,5 @@
+package io.reflectoring.solid.isp;
+
+interface IBurgerOrder{
+    void orderBurger(int quantity);
+}

solid/src/main/java/io/reflectoring/solid/isp/IFriesOrder.java

@@ -0,0 +1,5 @@
+package io.reflectoring.solid.isp;
+
+interface IFriesOrder {
+    void orderFries(int quantity);
+}

solid/src/main/java/io/reflectoring/solid/isp/IOrder.java

@@ -0,0 +1,6 @@
+package io.reflectoring.solid.isp;
+
+interface IOrder {
+    void orderBurger(int quantity);
+    void orderFries(int fries);
+}

solid/src/main/java/io/reflectoring/solid/isp/Main.java

@@ -0,0 +1,10 @@
+package io.reflectoring.solid.isp;
+
+class Main{
+    public static void main(String[] args){
+        OrderService comboOrderService = new ComboOrderService();
+        NewBurgerOrderService burgerService =
+            new OrderServiceObjectAdapter(new ComboOrderService());
+        burgerService.orderBurger(4);
+    }
+}

solid/src/main/java/io/reflectoring/solid/isp/NewBurgerOrderService.java

@@ -0,0 +1,5 @@
+package io.reflectoring.solid.isp;
+
+interface NewBurgerOrderService {
+    void orderBurger(int quantity);
+}

solid/src/main/java/io/reflectoring/solid/isp/NewFriesOrderService.java

@@ -0,0 +1,5 @@
+package io.reflectoring.solid.isp;
+
+interface NewFriesOrderService {
+    void orderFries(int fries);
+}

solid/src/main/java/io/reflectoring/solid/isp/Order.java

@@ -0,0 +1,5 @@
+package io.reflectoring.solid.isp;
+
+class Order {
+    // define order
+}

solid/src/main/java/io/reflectoring/solid/isp/OrderService.java

@@ -0,0 +1,7 @@
+package io.reflectoring.solid.isp;
+
+interface OrderService {
+    void orderBurger(int quantity);
+    void orderFries(int fries);
+    void orderCombo(int quantity, int fries);
+}

solid/src/main/java/io/reflectoring/solid/isp/OrderServiceObjectAdapter.java

@@ -0,0 +1,14 @@
+package io.reflectoring.solid.isp;
+
+class OrderServiceObjectAdapter implements NewBurgerOrderService {
+    private OrderService adaptee;
+    public OrderServiceObjectAdapter(OrderService adaptee) {
+        super();
+        this.adaptee = adaptee;
+    }
+
+    @Override
+    public void orderBurger(int quantity) {
+        adaptee.orderBurger(quantity);
+    }
+}

spring-boot/argumentresolver/.gitignore

@@ -0,0 +1,32 @@
+HELP.md
+.gradle
+build/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**
+!**/src/test/**
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+out/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/

spring-boot/argumentresolver/build.gradle

@@ -0,0 +1,28 @@
+plugins {
+	id 'org.springframework.boot' version '2.2.5.RELEASE'
+	id 'io.spring.dependency-management' version '1.0.9.RELEASE'
+	id 'java'
+}
+
+group = 'io.reflectoring'
+version = '0.0.1-SNAPSHOT'
+sourceCompatibility = '11'
+
+repositories {
+	mavenCentral()
+}
+
+dependencies {
+	implementation 'org.springframework.boot:spring-boot-starter'
+	implementation 'org.springframework.boot:spring-boot-starter-web'
+	testImplementation('org.springframework.boot:spring-boot-starter-test') {
+		exclude group: 'org.junit.vintage', module: 'junit-vintage-engine'
+	}
+
+	compileOnly 'org.projectlombok:lombok'
+	annotationProcessor 'org.projectlombok:lombok'
+}
+
+test {
+	useJUnitPlatform()
+}

spring-boot/argumentresolver/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.0.1-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

spring-boot/argumentresolver/gradlew

@@ -0,0 +1,172 @@
+#!/usr/bin/env sh
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+PRG="$0"
+# Need this for relative symlinks.
+while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+        PRG="$link"
+    else
+        PRG=`dirname "$PRG"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS=""
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+    echo "$*"
+}
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+        JAVACMD="$JAVA_HOME/bin/java"
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=$((i+1))
+    done
+    case $i in
+        (0) set -- ;;
+        (1) set -- "$args0" ;;
+        (2) set -- "$args0" "$args1" ;;
+        (3) set -- "$args0" "$args1" "$args2" ;;
+        (4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Escape application args
+save () {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
+}
+APP_ARGS=$(save "$@")
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+# by default we should be in the correct project dir, but when run from Finder on Mac, the cwd is wrong
+if [ "$(uname)" = "Darwin" ] && [ "$HOME" = "$PWD" ]; then
+  cd "$(dirname "$0")"
+fi
+
+exec "$JAVACMD" "$@"

spring-boot/argumentresolver/gradlew.bat

@@ -0,0 +1,84 @@
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS=
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

spring-boot/argumentresolver/settings.gradle

@@ -0,0 +1 @@
+rootProject.name = 'argumentresolver'

spring-boot/argumentresolver/src/main/java/io/reflectoring/argumentresolver/ArgumentresolverApplication.java

@@ -0,0 +1,13 @@
+package io.reflectoring.argumentresolver;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class ArgumentresolverApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(ArgumentresolverApplication.class, args);
+	}
+
+}

spring-boot/argumentresolver/src/main/java/io/reflectoring/argumentresolver/ErrorHandler.java

@@ -0,0 +1,15 @@
+package io.reflectoring.argumentresolver;
+
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.ControllerAdvice;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+
+@ControllerAdvice
+class ErrorHandler {
+
+  @ExceptionHandler(NotFoundException.class)
+  ResponseEntity<?> handleHttpStatusCodeException(NotFoundException e) {
+    return ResponseEntity.status(e.getStatusCode()).build();
+  }
+
+}

spring-boot/argumentresolver/src/main/java/io/reflectoring/argumentresolver/GitRepository.java

@@ -0,0 +1,12 @@
+package io.reflectoring.argumentresolver;
+
+
+import lombok.Value;
+
+@Value
+class GitRepository {
+
+  private final Long id;
+  private final String slug;
+
+}

spring-boot/argumentresolver/src/main/java/io/reflectoring/argumentresolver/GitRepositoryArgumentResolver.java

@@ -0,0 +1,38 @@
+package io.reflectoring.argumentresolver;
+
+import java.util.Optional;
+import lombok.RequiredArgsConstructor;
+import org.springframework.core.MethodParameter;
+import org.springframework.web.bind.support.WebDataBinderFactory;
+import org.springframework.web.context.request.NativeWebRequest;
+import org.springframework.web.context.request.ServletWebRequest;
+import org.springframework.web.method.support.HandlerMethodArgumentResolver;
+import org.springframework.web.method.support.ModelAndViewContainer;
+
+@RequiredArgsConstructor
+class GitRepositoryArgumentResolver implements HandlerMethodArgumentResolver {
+
+  private final GitRepositoryFinder gitRepositoryFinder;
+
+  @Override
+  public boolean supportsParameter(MethodParameter parameter) {
+    return parameter.getParameter().getType() == GitRepository.class;
+  }
+
+  @Override
+  public Object resolveArgument(
+      MethodParameter parameter,
+      ModelAndViewContainer mavContainer,
+      NativeWebRequest webRequest,
+      WebDataBinderFactory binderFactory) {
+
+    String requestPath = ((ServletWebRequest) webRequest).getRequest().getPathInfo();
+
+    String slug = requestPath
+        .substring(0, requestPath.indexOf("/", 1))
+        .replaceAll("^/", "");
+
+    return gitRepositoryFinder.findBySlug(slug)
+        .orElseThrow(NotFoundException::new);
+  }
+}

spring-boot/argumentresolver/src/main/java/io/reflectoring/argumentresolver/GitRepositoryArgumentResolverConfiguration.java

@@ -0,0 +1,20 @@
+package io.reflectoring.argumentresolver;
+
+import java.util.List;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Component;
+import org.springframework.web.method.support.HandlerMethodArgumentResolver;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
+
+@Component
+@RequiredArgsConstructor
+class GitRepositoryArgumentResolverConfiguration implements WebMvcConfigurer {
+
+  private final GitRepositoryFinder gitRepositoryFinder;
+
+  @Override
+  public void addArgumentResolvers(List<HandlerMethodArgumentResolver> resolvers) {
+    resolvers.add(new GitRepositoryArgumentResolver(gitRepositoryFinder));
+  }
+
+}

spring-boot/argumentresolver/src/main/java/io/reflectoring/argumentresolver/GitRepositoryFinder.java

@@ -0,0 +1,9 @@
+package io.reflectoring.argumentresolver;
+
+import java.util.Optional;
+
+public interface GitRepositoryFinder {
+
+  Optional<GitRepository> findBySlug(String slug);
+
+}

spring-boot/argumentresolver/src/main/java/io/reflectoring/argumentresolver/GitRepositoryId.java

@@ -0,0 +1,10 @@
+package io.reflectoring.argumentresolver;
+
+import lombok.Value;
+
+@Value
+class GitRepositoryId {
+
+  private final long value;
+
+}

spring-boot/argumentresolver/src/main/java/io/reflectoring/argumentresolver/GitRepositoryIdConverter.java

@@ -0,0 +1,13 @@
+package io.reflectoring.argumentresolver;
+
+import org.springframework.core.convert.converter.Converter;
+import org.springframework.stereotype.Component;
+
+@Component
+class GitRepositoryIdConverter implements Converter<String, GitRepositoryId> {
+
+  @Override
+  public GitRepositoryId convert(String source) {
+    return new GitRepositoryId(Long.parseLong(source));
+  }
+}

spring-boot/argumentresolver/src/main/java/io/reflectoring/argumentresolver/GitRepositoryIdWithValueOf.java

@@ -0,0 +1,17 @@
+package io.reflectoring.argumentresolver;
+
+import lombok.Value;
+
+@Value
+class GitRepositoryIdWithValueOf {
+
+  private final long value;
+
+  /**
+   * If we have a static valueOf(String) method, we don't need a Converter!
+   */
+  public static GitRepositoryIdWithValueOf valueOf(String value){
+    return new GitRepositoryIdWithValueOf(Long.parseLong(value));
+  }
+
+}

spring-boot/argumentresolver/src/main/java/io/reflectoring/argumentresolver/NotFoundException.java

@@ -0,0 +1,11 @@
+package io.reflectoring.argumentresolver;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.web.client.HttpStatusCodeException;
+
+public class NotFoundException extends HttpStatusCodeException {
+
+  protected NotFoundException() {
+    super(HttpStatus.NOT_FOUND);
+  }
+}

spring-boot/argumentresolver/src/test/java/io/reflectoring/argumentresolver/GitRepositoryArgumentResolverTest.java

@@ -0,0 +1,43 @@
+package io.reflectoring.argumentresolver;
+
+import static org.mockito.BDDMockito.given;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+import java.util.Optional;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
+import org.springframework.boot.test.mock.mockito.MockBean;
+import org.springframework.test.web.servlet.MockMvc;
+
+@WebMvcTest(controllers = GitRepositoryArgumentResolverTestController.class)
+class GitRepositoryArgumentResolverTest {
+
+  @Autowired
+  private MockMvc mockMvc;
+
+  @MockBean
+  private GitRepositoryFinder gitRepositoryFinder;
+
+  @Test
+  void resolvesSiteSuccessfully() throws Exception {
+
+    given(gitRepositoryFinder.findBySlug("my-repo"))
+        .willReturn(Optional.of(new GitRepository(1L, "my-repo")));
+
+    mockMvc.perform(get("/my-repo/contributors"))
+        .andExpect(status().isOk());
+  }
+
+  @Test
+  void notFoundOnUnknownSlug() throws Exception {
+
+    given(gitRepositoryFinder.findBySlug("unknownSlug"))
+        .willReturn(Optional.empty());
+
+    mockMvc.perform(get("/unknownSlug/contributors"))
+        .andExpect(status().isNotFound());
+  }
+
+}

spring-boot/argumentresolver/src/test/java/io/reflectoring/argumentresolver/GitRepositoryArgumentResolverTestController.java

@@ -0,0 +1,19 @@
+package io.reflectoring.argumentresolver;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+@RequestMapping(path = "/{repositorySlug}")
+class GitRepositoryArgumentResolverTestController {
+
+  @GetMapping("/contributors")
+  String listContributors(GitRepository gitRepository) {
+    assertThat(gitRepository.getId()).isEqualTo(1L);
+    return "test";
+  }
+
+}

spring-boot/argumentresolver/src/test/java/io/reflectoring/argumentresolver/GitRepositoryIdConverterTest.java

@@ -0,0 +1,27 @@
+package io.reflectoring.argumentresolver;
+
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
+import org.springframework.boot.test.mock.mockito.MockBean;
+import org.springframework.test.web.servlet.MockMvc;
+
+@WebMvcTest(controllers = GitRepositoryIdConverterTestController.class)
+class GitRepositoryIdConverterTest {
+
+  @Autowired
+  private MockMvc mockMvc;
+
+  @MockBean
+  private GitRepositoryFinder gitRepositoryFinder;
+
+  @Test
+  void resolvesRepositoryId() throws Exception {
+    mockMvc.perform(get("/repositories/42"))
+        .andExpect(status().isOk());
+  }
+
+}

spring-boot/argumentresolver/src/test/java/io/reflectoring/argumentresolver/GitRepositoryIdConverterTestController.java

@@ -0,0 +1,18 @@
+package io.reflectoring.argumentresolver;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+class GitRepositoryIdConverterTestController {
+
+  @GetMapping("/repositories/{repositoryId}")
+  String getRepository(@PathVariable("repositoryId") GitRepositoryId gitRepositoryId) {
+    assertThat(gitRepositoryId).isNotNull();
+    return "test";
+  }
+
+}

spring-boot/argumentresolver/src/test/java/io/reflectoring/argumentresolver/GitRepositoryIdWithValueOfTest.java

@@ -0,0 +1,27 @@
+package io.reflectoring.argumentresolver;
+
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
+import org.springframework.boot.test.mock.mockito.MockBean;
+import org.springframework.test.web.servlet.MockMvc;
+
+@WebMvcTest(controllers = GitRepositoryIdWithValueOfTestController.class)
+class GitRepositoryIdWithValueOfTest {
+
+  @Autowired
+  private MockMvc mockMvc;
+
+  @MockBean
+  private GitRepositoryFinder gitRepositoryFinder;
+
+  @Test
+  void resolvesRepositoryId() throws Exception {
+    mockMvc.perform(get("/repositories/42"))
+        .andExpect(status().isOk());
+  }
+
+}

spring-boot/argumentresolver/src/test/java/io/reflectoring/argumentresolver/GitRepositoryIdWithValueOfTestController.java

@@ -0,0 +1,18 @@
+package io.reflectoring.argumentresolver;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+class GitRepositoryIdWithValueOfTestController {
+
+  @GetMapping("/repositories/{repositoryId}")
+  String getRepository(@PathVariable("repositoryId") GitRepositoryIdWithValueOf gitRepositoryId) {
+    assertThat(gitRepositoryId).isNotNull();
+    return "test";
+  }
+
+}

spring-boot/boundaries/.gitignore

@@ -0,0 +1,32 @@
+HELP.md
+.gradle
+build/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**
+!**/src/test/**
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+out/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/

spring-boot/boundaries/build.gradle

@@ -0,0 +1,30 @@
+plugins {
+	id 'org.springframework.boot' version '2.2.5.RELEASE'
+	id 'io.spring.dependency-management' version '1.0.9.RELEASE'
+	id 'java'
+}
+
+group = 'io.reflectoring'
+version = '0.0.1-SNAPSHOT'
+sourceCompatibility = '1.8'
+
+repositories {
+	mavenCentral()
+}
+
+dependencies {
+	implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
+	compileOnly 'org.projectlombok:lombok'
+	runtimeOnly 'com.h2database:h2'
+	annotationProcessor 'org.projectlombok:lombok'
+	testImplementation('org.springframework.boot:spring-boot-starter-test') {
+		exclude group: 'org.junit.vintage', module: 'junit-vintage-engine'
+	}
+	// ArchUnit
+	testImplementation 'com.tngtech.archunit:archunit-junit5:0.13.1'
+	testImplementation 'org.reflections:reflections:0.9.10'
+}
+
+test {
+	useJUnitPlatform()
+}

spring-boot/boundaries/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.0.1-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

spring-boot/boundaries/gradlew

@@ -0,0 +1,172 @@
+#!/usr/bin/env sh
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+PRG="$0"
+# Need this for relative symlinks.
+while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+        PRG="$link"
+    else
+        PRG=`dirname "$PRG"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS=""
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+    echo "$*"
+}
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+        JAVACMD="$JAVA_HOME/bin/java"
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=$((i+1))
+    done
+    case $i in
+        (0) set -- ;;
+        (1) set -- "$args0" ;;
+        (2) set -- "$args0" "$args1" ;;
+        (3) set -- "$args0" "$args1" "$args2" ;;
+        (4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Escape application args
+save () {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
+}
+APP_ARGS=$(save "$@")
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+# by default we should be in the correct project dir, but when run from Finder on Mac, the cwd is wrong
+if [ "$(uname)" = "Darwin" ] && [ "$HOME" = "$PWD" ]; then
+  cd "$(dirname "$0")"
+fi
+
+exec "$JAVACMD" "$@"

spring-boot/boundaries/gradlew.bat

@@ -0,0 +1,84 @@
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS=
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

spring-boot/boundaries/settings.gradle

@@ -0,0 +1 @@
+rootProject.name = 'boundaries'

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/BoundariesApplication.java

@@ -0,0 +1,13 @@
+package io.reflectoring.boundaries;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class BoundariesApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(BoundariesApplication.class, args);
+	}
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/InternalPackage.java

@@ -0,0 +1,18 @@
+package io.reflectoring.boundaries;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Annotate a package-info.java file with this annotation to mark it as internal, i.e. no
+ * classes outside of that package may depend on any classes within that package.
+ */
+@Target(ElementType.PACKAGE)
+@Retention(RetentionPolicy.RUNTIME)
+@Documented
+public @interface InternalPackage {
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/api/Invoice.java

@@ -0,0 +1,11 @@
+package io.reflectoring.boundaries.billing.api;
+
+import lombok.Value;
+
+@Value
+public class Invoice {
+
+  private Long userId;
+  private double amount;
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/api/InvoiceCalculator.java

@@ -0,0 +1,9 @@
+package io.reflectoring.boundaries.billing.api;
+
+import java.time.LocalDate;
+
+public interface InvoiceCalculator {
+
+  Invoice calculateInvoice(Long userId, LocalDate fromDate, LocalDate toDate);
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/BillingConfiguration.java

@@ -0,0 +1,10 @@
+package io.reflectoring.boundaries.billing.internal;
+
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+@ComponentScan
+class BillingConfiguration {
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/BillingService.java

@@ -0,0 +1,27 @@
+package io.reflectoring.boundaries.billing.internal;
+
+import io.reflectoring.boundaries.billing.api.Invoice;
+import io.reflectoring.boundaries.billing.api.InvoiceCalculator;
+import io.reflectoring.boundaries.billing.internal.database.api.LineItem;
+import io.reflectoring.boundaries.billing.internal.database.api.ReadLineItems;
+import java.time.LocalDate;
+import java.util.List;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Component;
+
+@Component
+@RequiredArgsConstructor
+class BillingService implements InvoiceCalculator {
+
+  private final ReadLineItems readLineItems;
+
+  @Override
+  public Invoice calculateInvoice(Long userId, LocalDate fromDate, LocalDate toDate) {
+    List<LineItem> items = readLineItems.getLineItemsForUser(userId, fromDate, toDate);
+    double sum = items.stream()
+        .mapToDouble(LineItem::getAmount)
+        .sum();
+    return new Invoice(userId, sum);
+  }
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/batchjob/internal/BillingBatchJobConfiguration.java

@@ -0,0 +1,12 @@
+package io.reflectoring.boundaries.billing.internal.batchjob.internal;
+
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.scheduling.annotation.EnableScheduling;
+
+@Configuration
+@EnableScheduling
+@ComponentScan
+class BillingBatchJobConfiguration {
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/batchjob/internal/LoadInvoiceDataBatchJob.java

@@ -0,0 +1,42 @@
+package io.reflectoring.boundaries.billing.internal.batchjob.internal;
+
+import io.reflectoring.boundaries.billing.internal.database.api.WriteLineItems;
+import io.reflectoring.boundaries.billing.internal.database.api.LineItem;
+import java.time.LocalDate;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Random;
+import lombok.RequiredArgsConstructor;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.scheduling.annotation.Scheduled;
+import org.springframework.stereotype.Component;
+
+@RequiredArgsConstructor
+@Component
+class LoadInvoiceDataBatchJob {
+
+  private static final Logger logger = LoggerFactory.getLogger(LoadInvoiceDataBatchJob.class);
+  private static final Random random = new Random();
+  private final WriteLineItems writeLineItems;
+
+  @Scheduled(fixedRate = 5000)
+  void loadDataFromBillingSystem() {
+    List<LineItem> items = getLineItemsFromBillingSystem();
+    writeLineItems.saveLineItems(items);
+  }
+
+  private List<LineItem> getLineItemsFromBillingSystem() {
+    // imagine this list is loaded from a 3rd party system
+    return Arrays.asList(
+        lineItem("bread"),
+        lineItem("butter"),
+        lineItem("toilet paper")
+    );
+  }
+
+  private LineItem lineItem(String itemName) {
+    return new LineItem(42L, itemName, 42.42d, LocalDate.now().minusDays(random.nextInt(10)));
+  }
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/batchjob/internal/package-info.java

@@ -0,0 +1,4 @@
+@InternalPackage
+package io.reflectoring.boundaries.billing.internal.batchjob.internal;
+
+import io.reflectoring.boundaries.InternalPackage;

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/database/api/LineItem.java

@@ -0,0 +1,14 @@
+package io.reflectoring.boundaries.billing.internal.database.api;
+
+import java.time.LocalDate;
+import lombok.Value;
+
+@Value
+public class LineItem {
+
+  private final Long userId;
+  private final String name;
+  private final double amount;
+  private final LocalDate date;
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/database/api/ReadLineItems.java

@@ -0,0 +1,10 @@
+package io.reflectoring.boundaries.billing.internal.database.api;
+
+import java.time.LocalDate;
+import java.util.List;
+
+public interface ReadLineItems {
+
+  List<LineItem> getLineItemsForUser(Long userId, LocalDate startDate, LocalDate endDate);
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/database/api/WriteLineItems.java

@@ -0,0 +1,9 @@
+package io.reflectoring.boundaries.billing.internal.database.api;
+
+import java.util.List;
+
+public interface WriteLineItems {
+
+  void saveLineItems(List<LineItem> lineItems);
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/database/internal/BillingDatabase.java

@@ -0,0 +1,31 @@
+package io.reflectoring.boundaries.billing.internal.database.internal;
+
+import io.reflectoring.boundaries.billing.internal.database.api.LineItem;
+import io.reflectoring.boundaries.billing.internal.database.api.ReadLineItems;
+import io.reflectoring.boundaries.billing.internal.database.api.WriteLineItems;
+import java.time.LocalDate;
+import java.util.List;
+import java.util.stream.Collectors;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Component;
+
+@Component
+@RequiredArgsConstructor
+class BillingDatabase implements WriteLineItems, ReadLineItems {
+
+  private final LineItemRepository lineItemRepository;
+
+  @Override
+  public void saveLineItems(List<LineItem> lineItems) {
+    for (LineItem lineItem : lineItems) {
+      lineItemRepository.save(LineItemJpaEntity.fromDomainObject(lineItem));
+    }
+  }
+
+  @Override
+  public List<LineItem> getLineItemsForUser(Long userId, LocalDate startDate, LocalDate endDate) {
+    return lineItemRepository.findByUserIdAndDateBetween(userId, startDate, endDate).stream()
+        .map(LineItemJpaEntity::toDomainObject)
+        .collect(Collectors.toList());
+  }
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/database/internal/BillingDatabaseConfiguration.java

@@ -0,0 +1,12 @@
+package io.reflectoring.boundaries.billing.internal.database.internal;
+
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
+
+@Configuration
+@EnableJpaRepositories
+@ComponentScan
+class BillingDatabaseConfiguration {
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/database/internal/LineItemJpaEntity.java

@@ -0,0 +1,43 @@
+package io.reflectoring.boundaries.billing.internal.database.internal;
+
+import io.reflectoring.boundaries.billing.internal.database.api.LineItem;
+import java.time.LocalDate;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+@Entity
+@Data
+@AllArgsConstructor
+@NoArgsConstructor
+class LineItemJpaEntity {
+
+  @Id
+  @GeneratedValue
+  private Long userId;
+  private String name;
+  private Double amount;
+  private LocalDate date;
+
+  static LineItemJpaEntity fromDomainObject(LineItem lineItem) {
+    return new LineItemJpaEntity(
+        lineItem.getUserId(),
+        lineItem.getName(),
+        lineItem.getAmount(),
+        lineItem.getDate()
+    );
+  }
+
+  LineItem toDomainObject(){
+    return new LineItem(
+        this.userId,
+        this.name,
+        this.amount,
+        this.date
+    );
+  }
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/database/internal/LineItemRepository.java

@@ -0,0 +1,11 @@
+package io.reflectoring.boundaries.billing.internal.database.internal;
+
+import java.time.LocalDate;
+import java.util.List;
+import org.springframework.data.repository.CrudRepository;
+
+interface LineItemRepository extends CrudRepository<LineItemJpaEntity, Long> {
+
+  List<LineItemJpaEntity> findByUserIdAndDateBetween(Long userId, LocalDate startDate, LocalDate endDate);
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/database/internal/package-info.java

@@ -0,0 +1,4 @@
+@InternalPackage
+package io.reflectoring.boundaries.billing.internal.database.internal;
+
+import io.reflectoring.boundaries.InternalPackage;

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/package-info.java

@@ -0,0 +1,4 @@
+@InternalPackage
+package io.reflectoring.boundaries.billing.internal;
+
+import io.reflectoring.boundaries.InternalPackage;

spring-boot/boundaries/src/test/java/io/reflectoring/boundaries/BoundariesApplicationTests.java

@@ -1,13 +1,13 @@
-package io.reflectoring.codefirst;
+package io.reflectoring.boundaries;
 
 import org.junit.jupiter.api.Test;
 import org.springframework.boot.test.context.SpringBootTest;
 
 @SpringBootTest
-class CodeFirstApplicationTests {
+class BoundariesApplicationTests {
 
-    @Test
-    void contextLoads() {
-    }
+	@Test
+	void contextLoads() {
+	}
 
 }

spring-boot/boundaries/src/test/java/io/reflectoring/boundaries/InternalPackageTests.java

@@ -0,0 +1,63 @@
+package io.reflectoring.boundaries;
+
+import static com.tngtech.archunit.lang.syntax.ArchRuleDefinition.noClasses;
+import static org.assertj.core.api.Assertions.assertThat;
+
+import com.tngtech.archunit.core.domain.JavaClasses;
+import com.tngtech.archunit.core.importer.ClassFileImporter;
+import java.io.IOException;
+import java.util.List;
+import java.util.stream.Collectors;
+import org.junit.jupiter.api.Test;
+import org.reflections.Reflections;
+
+/**
+ * Evaluates {@link InternalPackage} annotations and checks that those packages are not accessed from the outside.
+ */
+class InternalPackageTests {
+
+  private static final String BASE_PACKAGE = "io.reflectoring";
+  private final JavaClasses analyzedClasses = new ClassFileImporter().importPackages(BASE_PACKAGE);
+
+  @Test
+  void internalPackagesAreNotAccessedFromOutside() throws IOException {
+
+    // so that the test will break when the base package is re-named
+    assertPackageExists(BASE_PACKAGE);
+
+    List<String> internalPackages = internalPackages(BASE_PACKAGE);
+
+    for (String internalPackage : internalPackages) {
+      assertPackageIsNotAccessedFromOutside(internalPackage);
+    }
+
+  }
+
+  /**
+   * Finds all packages annotated with @{@link InternalPackage}.
+   */
+  private List<String> internalPackages(String basePackage) {
+    Reflections reflections = new Reflections(basePackage);
+    return reflections.getTypesAnnotatedWith(InternalPackage.class).stream()
+        .map(c -> c.getPackage().getName())
+        .collect(Collectors.toList());
+  }
+
+  void assertPackageIsNotAccessedFromOutside(String internalPackage) {
+    noClasses().that().resideOutsideOfPackage(packageMatcher(internalPackage))
+        .should().dependOnClassesThat().resideInAPackage(packageMatcher(internalPackage))
+        .check(analyzedClasses);
+  }
+
+  void assertPackageExists(String packageName) {
+    assertThat(analyzedClasses.containPackage(packageName))
+        .as("package %s exists", packageName)
+        .isTrue();
+  }
+
+  private String packageMatcher(String fullyQualifiedPackage) {
+    return fullyQualifiedPackage + "..";
+  }
+
+
+}