Kogito with persistence and events strong consistency powered by Spring Boot, MongoDB, Debezium and Kafka

Description

This example shows how to enable storing Kogito process data and events to MongoDB.

By doing so, it allows demonstrating how to use the transactional outbox pattern with Debezium, which then reads these events and publishes to Kafka.

Run the Example End-to-End

1. Build the Kogito App

mvn clean package -Dcontainer

2. Deploy Kogito App, MongoDB, Debezium and Kafka

docker compose up

3. Check if Debezium is in RUNNING state

curl http://localhost:8083/connectors/kogito-connector/status

4. Interact with the Kogito App (e.g. create an order) and generate some Kogito events

curl -d '{"approver" : "john", "order" : {"orderNumber" : "12345", "shipped" : false}}' -H "Content-Type: application/json" -X POST http://localhost:8080/orders

5. Browse the Kafka messages with Kafdrop web UI at http://localhost:9000/

6. With the Kafka broker info from step 8, run the Kogito Data Index Service with MongoDB to consume Kafka messages: https://github.com/apache/incubator-kie-kogito-runtimes/wiki/Data-Index-Service

7. Shut down the cluster

docker compose down

Kogito App Example Usage

Once the service is up and running, you can use the following examples to interact with the service.

POST /orders

Allows to create a new order with the given data:

curl -d '{"approver" : "john", "order" : {"orderNumber" : "12345", "shipped" : false}}' -H "Content-Type: application/json" -X POST http://localhost:8080/orders

or on windows

curl -d "{\"approver\" : \"john\", \"order\" : {\"orderNumber\" : \"12345\", \"shipped\" : false}}" -H "Content-Type: application/json" -X POST http://localhost:8080/orders

As response the updated order is returned.

GET /orders

Returns list of orders currently active:

curl -X GET http://localhost:8080/orders

As response an array of orders is returned.

GET /orders/{id}

Returns order with given id (if active):

curl -X GET http://localhost:8080/orders/1

As response a single order is returned if found, otherwise 404 Not Found is returned.

DELETE /orders/{id}

Cancels order with given id

curl -X DELETE http://localhost:8080/orders/1

GET /orderItems

Getting order items sub processes

curl -X GET http://localhost:8080/orderItems

Example response:

[
  {
    "id":"66c11e3e-c211-4cee-9a07-848b5e861bc5",
    "order":
    {
      "orderNumber":"12345",
      "shipped":false,
      "total":0.537941914075738
    }
  }
]

GET /orderItems/{id}/tasks

Getting user tasks awaiting user action

curl -X GET http://localhost:8080/orderItems/66c11e3e-c211-4cee-9a07-848b5e861bc5/tasks?user=john

Example response:

[
  {"id":"62f1c985-d31c-4ead-9906-2fe8d05937f0","name":"Verify order"}
]

GET /orderItems/{id}/Verify_order/{tid}

Getting user task details

curl -X GET http://localhost:8080/orderItems/66c11e3e-c211-4cee-9a07-848b5e861bc5/Verify_order/62f1c985-d31c-4ead-9906-2fe8d05937f0?user=john

Example response:

{
  "id":"62f1c985-d31c-4ead-9906-2fe8d05937f0",
  "input1":
  {
    "orderNumber":"12345",
    "shipped":false,
    "total":0.537941914075738
  },
  "name":"Verify order"
}

POST /orderItems/{id}/Verify_order/{tid}

Complete user task

curl -d '{}' -H "Content-Type: application/json" -X POST http://localhost:8080/orderItems/66c11e3e-c211-4cee-9a07-848b5e861bc5/Verify_order/62f1c985-d31c-4ead-9906-2fe8d05937f0?user=john

As response the updated order is returned.

Example response:

{
  "id":"66c11e3e-c211-4cee-9a07-848b5e861bc5",
  "order":
  {
    "orderNumber":"12345",
    "shipped":false,
    "total":0.537941914075738
  }
}

References

Outbox pattern: https://microservices.io/patterns/data/transactional-outbox.html

Debezium Connector: https://debezium.io/blog/2019/02/19/reliable-microservices-data-exchange-with-the-outbox-pattern/

debezium-examples: https://github.com/debezium/debezium-examples/blob/main/tutorial/README.md#using-mongodb

debezium-images: https://github.com/debezium/docker-images/tree/main/examples/mongodb/