== What is this app?
This is an example using Spring Cloud Stream to model a subset of a purchasing system. This e2e project showcases the following
features:
* Avro messaging
* Confluent Schema Registry
* Event-carried state transfer pattern
* KStream processing with a join operation
=== Running the app:
Start the Confluent Platform:
```
git clone https://github.com/confluentinc/cp-docker-images
cd cp-docker-images
git checkout 5.2.1-post
cd examples/cp-all-in-one/
docker-compose up -d --build
```
Go to the root of the sample project and do:
`./mvnw clean package`
`java -jar customer-service/target/customer-service-0.0.1-SNAPSHOT.jar`
`java -jar order-service/target/order-service-0.0.1-SNAPSHOT.jar`
`java -jar shipping-service/target/shipping-service-0.0.1-SNAPSHOT.jar`
Start two https://github.com/edenhill/kafkacat[kafkacat] processes to examine topic information:
```
kafkacat -b localhost:9092 -t customer -C \
-f '\nKey (%K bytes): %k
Value (%S bytes): %s
Timestamp: %T
Partition: %p
Offset: %o
Headers: %h\n'
```
```
kafkacat -b localhost:9092 -t order -C \
-f '\nKey (%K bytes): %k
Value (%S bytes): %s
Timestamp: %T
Partition: %p
Offset: %o
Headers: %h\n'
```
Create a customer:
`curl -X POST -H "content-type: application/json" http://localhost:8084/customers -d '{"id":1,"name":"John Doe","address":"Elm Street"}'`
Create an order for that customer:
`curl -X POST http://localhost:8085/orders -H "content-type: application/json" -d '{"id":1,"productId":100,"customerId":1}'`
Check the kafkacat output to verify that there is a record in the customer topic, and two in the order topic, corresponding
to the OrderCreatedEvent from customer-service and the OrderShippedEvent from shipping-service.
Customer topic kafkacat output:
```
Key (4 bytes):
Value (26 bytes): John DoeElm Street
Timestamp: 1561153134430
Partition: 0
Offset: 0
Headers:
```
Order topic kafkacat output:
```
Key (4 bytes):
Value (9 bytes): ?
Timestamp: 1561153313512
Partition: 0
Offset: 0
Headers:
Key (4 bytes):
Value (28 bytes): ?John DoeElm Street
Timestamp: 1561153313512
Partition: 0
Offset: 1
Headers:
```
