ZeeQS - Zeebe Query Service

A Zeebe community extension that provides a GraphQL query API over Zeebe's data. The data is imported from the broker using an exporter (e.g. Hazelcast, Elasticsearch) and aggregated in the service.

Usage

The application provides an endpoint /graphql for GraphQL queries.

A query can be send via HTTP POST request and a JSON body containing the query. For example:

curl \
  -X POST \
  -H "Content-Type: application/json" \
  --data '{ "query": "{ workflows { nodes { key } } }" }' \
  http://localhost:9000/graphql

While development, the graph can be explored using the integrated GraphiQL: http://localhost:9000/graphiql

Queries

The API provide the following queries:

• workflows
• workflowInstances
• jobs
• messages
• incidents

And additional queries to request a single object by its key (e.g. workflow(key: "2251799813685249")).

Pagination

In order to limit the response size and the query processing, each list query uses pagination to return only a subset of the data. By default, it returns the first 10 items of the list.

In addition to the items, the query result contains also the total count of the items.

{
  workflows(limit: 10, page: 0) {
    totalCount
    nodes {
      key
    }
  }
}

Filters

Some queries allow to filter the result by passing arguments in the query.

{
  workflowInstances(stateIn: [ACTIVATED]) {
    nodes {
      key
    }
  }
}

Examples

Get workflows including their workflow instance count:

{
  workflows {
    totalCount
    nodes {
      key
      bpmnProcessId
      version
      workflowInstances {
        totalCount
      }
    }
  }
}

Query Response

{
  "data": {
    "workflows": {
      "totalCount": 3,
      "nodes": [
        {
          "key": "2251799813685249",
          "bpmnProcessId": "demo-process",
          "version": 1,
          "workflowInstances": {
            "totalCount": 3
          }
        },
        {
          "key": "2251799813685251",
          "bpmnProcessId": "demo-2",
          "version": 1,
          "workflowInstances": {
            "totalCount": 2
          }
        },
        {
          "key": "2251799813685269",
          "bpmnProcessId": "demo-3",
          "version": 1,
          "workflowInstances": {
            "totalCount": 1
          }
        }
      ]
    }
  }
}

Get workflow instances that are active including their active element instances:

{
  workflowInstances(stateIn: [ACTIVATED]) {
    totalCount
    nodes {
      key
      state
      workflow {
        bpmnProcessId
      }
      elementInstances(stateIn: [ACTIVATED]) {
        elementId
        elementName
        bpmnElementType
        state
      }
    }
  }
}

Query Response

{
  "data": {
    "workflowInstances": {
      "totalCount": 6,
      "nodes": [
        {
          "key": "2251799813685261",
          "state": "ACTIVATED",
          "workflow": {
            "bpmnProcessId": "demo-process"
          },
          "elementInstances": [
            {
              "elementId": "demo-process",
              "elementName": null,
              "bpmnElementType": "PROCESS",
              "state": "ACTIVATED"
            },
            {
              "elementId": "ServiceTask_0f8l2yf",
              "elementName": "task 3",
              "bpmnElementType": "SERVICE_TASK",
              "state": "ACTIVATED"
            }
          ]
        },
        {
          "key": "2251799813685271",
          "state": "ACTIVATED",
          "workflow": {
            "bpmnProcessId": "demo-2"
          },
          "elementInstances": [
            {
              "elementId": "demo-2",
              "elementName": null,
              "bpmnElementType": "PROCESS",
              "state": "ACTIVATED"
            },
            {
              "elementId": "ServiceTask_0mhbd5b",
              "elementName": "task 3",
              "bpmnElementType": "SERVICE_TASK",
              "state": "ACTIVATED"
            }
          ]
        },
        {
          "key": "2251799813685277",
          "state": "ACTIVATED",
          "workflow": {
            "bpmnProcessId": "demo-2"
          },
          "elementInstances": [
            {
              "elementId": "demo-2",
              "elementName": null,
              "bpmnElementType": "PROCESS",
              "state": "ACTIVATED"
            },
            {
              "elementId": "ServiceTask_19bf066",
              "elementName": "task 1",
              "bpmnElementType": "SERVICE_TASK",
              "state": "ACTIVATED"
            }
          ]
        },
        {
          "key": "2251799813685287",
          "state": "ACTIVATED",
          "workflow": {
            "bpmnProcessId": "demo-3"
          },
          "elementInstances": [
            {
              "elementId": "demo-3",
              "elementName": null,
              "bpmnElementType": "PROCESS",
              "state": "ACTIVATED"
            },
            {
              "elementId": "ServiceTask_0t5azxx",
              "elementName": "task 2",
              "bpmnElementType": "SERVICE_TASK",
              "state": "ACTIVATED"
            }
          ]
        },
        {
          "key": "2251799813685304",
          "state": "ACTIVATED",
          "workflow": {
            "bpmnProcessId": "demo-process"
          },
          "elementInstances": [
            {
              "elementId": "demo-process",
              "elementName": null,
              "bpmnElementType": "PROCESS",
              "state": "ACTIVATED"
            },
            {
              "elementId": "ServiceTask_01flslu",
              "elementName": "task 2",
              "bpmnElementType": "SERVICE_TASK",
              "state": "ACTIVATED"
            }
          ]
        },
        {
          "key": "2251799813685310",
          "state": "ACTIVATED",
          "workflow": {
            "bpmnProcessId": "demo-process"
          },
          "elementInstances": [
            {
              "elementId": "demo-process",
              "elementName": null,
              "bpmnElementType": "PROCESS",
              "state": "ACTIVATED"
            },
            {
              "elementId": "ServiceTask_0m7fzva",
              "elementName": "task 1",
              "bpmnElementType": "SERVICE_TASK",
              "state": "ACTIVATED"
            }
          ]
        }
      ]
    }
  }
}

Get jobs that are activate (i.e. not completed or canceled) and have one of the given job types:

{
  jobs(stateIn: [ACTIVATABLE, ACTIVATED], jobTypeIn: ["task-1", "task-2", "task-3"]) {
    totalCount
    nodes {
      key
      jobType
      state
      elementInstance {
        elementId
        elementName
        workflowInstance {
          key
          workflow {
            key
            bpmnProcessId
          }
        }
      }
    }
  }
}

Query Response

{
  "data": {
    "jobs": {
      "totalCount": 5,
      "nodes": [
        {
          "key": "2251799813685282",
          "jobType": "task-1",
          "state": "ACTIVATABLE",
          "elementInstance": {
            "elementId": "ServiceTask_19bf066",
            "elementName": "task 1",
            "workflowInstance": {
              "key": "2251799813685277",
              "workflow": {
                "key": "2251799813685251",
                "bpmnProcessId": "demo-2"
              }
            }
          }
        },
        {
          "key": "2251799813685303",
          "jobType": "task-2",
          "state": "ACTIVATABLE",
          "elementInstance": {
            "elementId": "ServiceTask_0t5azxx",
            "elementName": "task 2",
            "workflowInstance": {
              "key": "2251799813685287",
              "workflow": {
                "key": "2251799813685269",
                "bpmnProcessId": "demo-3"
              }
            }
          }
        },
        {
          "key": "2251799813685315",
          "jobType": "task-1",
          "state": "ACTIVATABLE",
          "elementInstance": {
            "elementId": "ServiceTask_0m7fzva",
            "elementName": "task 1",
            "workflowInstance": {
              "key": "2251799813685310",
              "workflow": {
                "key": "2251799813685249",
                "bpmnProcessId": "demo-process"
              }
            }
          }
        },
        {
          "key": "2251799813685321",
          "jobType": "task-3",
          "state": "ACTIVATABLE",
          "elementInstance": {
            "elementId": "ServiceTask_0f8l2yf",
            "elementName": "task 3",
            "workflowInstance": {
              "key": "2251799813685261",
              "workflow": {
                "key": "2251799813685249",
                "bpmnProcessId": "demo-process"
              }
            }
          }
        },
        {
          "key": "2251799813685324",
          "jobType": "task-2",
          "state": "ACTIVATABLE",
          "elementInstance": {
            "elementId": "ServiceTask_01flslu",
            "elementName": "task 2",
            "workflowInstance": {
              "key": "2251799813685304",
              "workflow": {
                "key": "2251799813685249",
                "bpmnProcessId": "demo-process"
              }
            }
          }
        }
      ]
    }
  }
}

Install

Docker

The docker image for the ZeeQS application is published to DockerHub.

docker pull camunda/zeeqs:latest

• ensure that a Zeebe broker is running with a Hazelcast exporter (>= 0.8.0-alpha1)
• forward the Hazelcast port to the docker container (default: 5701)
• configure the connection to Hazelcast by setting zeebe.client.worker.hazelcast.connection (default: localhost:5701)

For a local setup, the repository contains a docker-compose file. It starts a Zeebe broker with the Hazelcast exporter and the ZeeQS application.

mvn clean install -DskipTests
cd docker
docker-compose up

• the GraphQL endpoint is available under the port 9000:

Manual

1. Download the latest application JAR (zeeqs-%{VERSION}.jar )

2. Start the application java -jar zeeqs-{VERSION}.jar

Configuration

The application is a Spring Boot application. The configuration can be changed via environment variables or an application.yaml file. See also the following resources:

• Spring Boot Configuration

By default, the port is set to 9000 and the database is only in-memory (i.e. not persistent).

zeebe:
  client:
    worker:
      hazelcast:
        connection: localhost:5701
        connectionTimeout: PT1M
        ringbuffer: zeebe
        connectionInitialBackoff: PT15S
        connectionBackoffMultiplier: 2.0
        connectionMaxBackoff: PT30S

spring:

  datasource:
    url: jdbc:h2:mem:zeebe-monitor;DB_CLOSE_DELAY=-1
    username: sa
    password:
    driverClassName: org.h2.Driver

  jpa:
    database-platform: org.hibernate.dialect.H2Dialect
    hibernate:
      ddl-auto: create

server:
  port: 9000

Using a different database, for example, PostgreSQL:

• change the following database configuration settings

- spring.datasource.url=jdbc:postgresql://db:5432/postgres
- spring.datasource.username=postgres
- spring.datasource.password=zeebe
- spring.datasource.driverClassName=org.postgresql.Driver
- spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.PostgreSQLDialect

• add the database driver JAR to the classpath
  • using docker, the JAR should be mounted to the /app/libs/ folder (e.g. /app/libs/postgresql-42.2.12.jar)

Full docker-compose.yml with PostgreSQL

version: "2"

networks:
  zeebe_network:
    driver: bridge

services:
  zeebe:
    container_name: zeebe_broker
    image: camunda/zeebe:0.23.0
    environment:
      - ZEEBE_LOG_LEVEL=debug
    ports:
      - "26500:26500"
      - "9600:9600"
      - "5701:5701"
    volumes:
      - ../target/exporter/zeebe-hazelcast-exporter.jar:/usr/local/zeebe/exporters/zeebe-hazelcast-exporter.jar
      - ./application.yaml:/usr/local/zeebe/config/application.yaml
    networks:
      - zeebe_network
      
  zeeqs:
    container_name: zeeqs
    image: camunda/zeeqs:latest
    environment:
      - zeebe.client.worker.hazelcast.connection=zeebe:5701
      - spring.datasource.url=jdbc:postgresql://db:5432/postgres
      - spring.datasource.username=postgres
      - spring.datasource.password=zeebe
      - spring.datasource.driverClassName=org.postgresql.Driver
      - spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.PostgreSQLDialect
    volumes:
      - ./lib/postgresql-42.2.12.jar:/app/libs/postgresql-42.2.12.jar
    ports:
      - "9000:9000"
    depends_on:
      - db
    networks:
      - zeebe_network

  db:
    image: postgres:12.2
    restart: always
    environment:
      POSTGRES_PASSWORD: zeebe
    volumes:
      - database-data:/var/lib/postgresql/data/
    networks:
      - zeebe_network

volumes:
  database-data:

Build from Source

Build with Maven

mvn clean install

Code of Conduct

This project adheres to the Contributor Covenant Code of Conduct. By participating, you are expected to uphold this code. Please report unacceptable behavior to [email protected].

License

Apache License, Version 2.0