#35 springboot: external read - Environment

springboot/external-read/src/main/java/hello/ExternalReadApplication.java

@@ -1,9 +1,12 @@
 package hello;
 
+import hello.config.MyDataSourceEnvConfig;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.annotation.Import;
 
-@SpringBootApplication
+@Import(MyDataSourceEnvConfig.class)
+@SpringBootApplication(scanBasePackages = "hello.datasource")
 public class ExternalReadApplication {
 
     public static void main(String[] args) {

springboot/external-read/src/main/java/hello/config/MyDataSourceEnvConfig.java

@@ -0,0 +1,31 @@
+package hello.config;
+
+import hello.datasource.MyDataSource;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.core.env.Environment;
+
+import java.time.Duration;
+import java.util.List;
+
+@Slf4j
+@Configuration
+@RequiredArgsConstructor
+public class MyDataSourceEnvConfig {
+
+    private final Environment env;
+
+    @Bean
+    public MyDataSource myDataSource() {
+        String url = env.getProperty("my.datasource.url");
+        String username = env.getProperty("my.datasource.username");
+        String password = env.getProperty("my.datasource.password");
+        int maxConnection = env.getProperty("my.datasource.etc.max-connection", Integer.class);
+        Duration timeout = env.getProperty("my.datasource.etc.timeout", Duration.class);
+        List<String> options = env.getProperty("my.datasource.etc.options", List.class);
+
+        return new MyDataSource(url,username, password, maxConnection, timeout, options);
+    }
+}

springboot/external-read/src/main/java/hello/datasource/MyDataSource.java

@@ -0,0 +1,30 @@
+package hello.datasource;
+
+import jakarta.annotation.PostConstruct;
+import lombok.AllArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+
+import java.time.Duration;
+import java.util.List;
+
+@Slf4j
+@AllArgsConstructor
+public class MyDataSource {
+
+    private String url;
+    private String username;
+    private String password;
+    private int maxConnection;
+    private Duration timeout;
+    private List<String> options;
+
+    @PostConstruct
+    public void init() {
+        log.info("url={}", url);
+        log.info("username={}", username);
+        log.info("password={}", password);
+        log.info("maxConnection={}", maxConnection);
+        log.info("timeout={}", timeout);
+        log.info("options={}", options);
+    }
+}

springboot/external-read/src/main/resources/application.properties

@@ -1 +1,6 @@
-
+my.datasource.url=local.db.com
+my.datasource.username=username
+my.datasource.password=password
+my.datasource.etc.max-connection=1
+my.datasource.etc.timeout=3500ms
+my.datasource.etc.options=CACHE,ADMIN