# Process Runtime API

The **Process Runtime API** provides a set of RESTful endpoints that allow external systems to interact with **process flows** managed by the ONEWEB Process Engine.

These APIs support standard operations required to **start processes**, **manage tasks**, **assign work**, and **control runtime behavior** of process instances.

This section documents all available Process Runtime API methods and explains their functionality.\
All endpoints are accessed relative to the application **context root** and are subject to the same authentication and authorization rules defined for ONEWEB APIs.

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### API Capabilities

Using the Process Runtime API, clients can:

* Start a new process flow
* Claim and complete tasks
* Retrieve tasks by instance, user, role, or group
* Assign tasks or entire process instances to users
* Read runtime task variables
* Refresh process runtime cache

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### Start Process

#### `POST /BPMREST/service/runtime/process/start`

Starts a new process flow.

* **Description**\
  Initiates a new process instance using the configured process definition.
* **HTTP Method**\
  `POST`

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#### Legacy Start Process (Not Recommended)

#### `POST /BPMREST/service/runtime/process/{processName}/start`

* **Description**\
  Legacy API used to start a process flow by process name.\
  This endpoint is **not recommended** and should be avoided in new integrations.
* **HTTP Method**\
  `POST`

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### Task Management APIs

#### Claim Task

#### `POST /BPMREST/service/runtime/tasks/{taskId}/claim?user={username}`

* **Description**\
  Claims a task for a specific user.
* **HTTP Method**\
  `POST`

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#### Complete Task

#### `POST /BPMREST/service/runtime/tasks/{taskId}/complete?user={username}`

* **Description**\
  Completes a task assigned to the specified user, advancing the process flow.
* **HTTP Method**\
  `POST`

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#### Get Tasks by Process Instance

#### `GET /BPMREST/service/runtime/instance/{instanceId}/tasks`

* **Description**\
  Retrieves all tasks associated with a specific process instance ID.
* **HTTP Method**\
  `GET`

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#### Get Tasks by User, Role, or Group

#### `GET /BPMREST/service/runtime/tasks?{group|role|user}={name}`

* **Description**\
  Retrieves tasks assigned to a specific **user**, **role**, or **group**.
* **HTTP Method**\
  `GET`

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### Task Data APIs

#### Get Task Variables

#### `POST /BPMREST/service/runtime/tasks/{taskId}/variables`

* **Description**\
  Retrieves all runtime variables associated with the specified task.
* **HTTP Method**\
  `POST`

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### Assignment APIs

#### Assign Task to Users

#### `POST /BPMREST/service/runtime/tasks/{taskId}/assign?user={user1}&user={user2}&...`

* **Description**\
  Assigns a task to one or more users.
* **HTTP Method**\
  `POST`

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#### Assign Process Instance to User

#### `POST /BPMREST/service/runtime/instance/{instanceId}/tasks/assign?user={username}`

* **Description**\
  Assigns all tasks within a process instance to a specific user.
* **HTTP Method**\
  `POST`

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### Runtime Maintenance APIs

#### Refresh Process Cache (All Processes)

#### `POST /BPMREST/service/runtime/refreshCache`

* **Description**\
  Refreshes runtime cache for all process definitions.
* **HTTP Method**\
  `POST`

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#### Refresh Process Cache (Specific Process)

#### `POST /BPMREST/service/runtime/classAction`

* **Description**\
  Refreshes runtime cache for a specific process.
* **HTTP Method**\
  `POST`

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### Summary

The **Process Runtime API** enables full lifecycle interaction with process flows in ONEWEB.

Key characteristics:

* REST‑based interface for process management
* Supports both process‑level and task‑level operations
* Enables user‑centric task handling and assignment
* Allows runtime introspection through variables
* Provides cache management for process definitions

This API is essential for **workflow automation**, **task orchestration**, and **integration with external systems**.


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