--- type: docs title: "Workflow API reference" linkTitle: "Workflow API" description: "Detailed documentation on the workflow API" weight: 300 --- {{% alert title="Note" color="primary" %}} Dapr Workflow is currently in beta. [See known limitations for {{% dapr-latest-version cli="true" %}}]({{< ref "workflow-overview.md#limitations" >}}). {{% /alert %}} Dapr provides users with the ability to interact with workflows and comes with a built-in `dapr` component. ## Start workflow request Start a workflow instance with the given name and optionally, an instance ID. ``` POST http://localhost:3500/v1.0/workflows///start[?instanceID=] ``` Note that workflow instance IDs can only contain alphanumeric characters, underscores, and dashes. ### URL parameters Parameter | Description --------- | ----------- `workflowComponentName` | Use `dapr` for Dapr Workflows `workflowName` | Identify the workflow type `instanceID` | (Optional) Unique value created for each run of a specific workflow ### Request content Any request content will be passed to the workflow as input. The Dapr API passes the content as-is without attempting to interpret it. ### HTTP response codes Code | Description ---- | ----------- `202` | Accepted `400` | Request was malformed `500` | Request formatted correctly, error in dapr code or underlying component ### Response content The API call will provide a response similar to this: ```json { "instanceID": "12345678" } ``` ## Terminate workflow request Terminate a running workflow instance with the given name and instance ID. ``` POST http://localhost:3500/v1.0/workflows///terminate ``` {{% alert title="Note" color="primary" %}} Terminating a workflow terminates all of the child workflows created by the workflow instance. Terminating a workflow has no effect on any in-flight activity executions that were started by the terminated instance. {{% /alert %}} ### URL parameters Parameter | Description --------- | ----------- `workflowComponentName` | Use `dapr` for Dapr Workflows `instanceId` | Unique value created for each run of a specific workflow ### HTTP response codes Code | Description ---- | ----------- `202` | Accepted `400` | Request was malformed `500` | Request formatted correctly, error in dapr code or underlying component ### Response content This API does not return any content. ## Raise Event request For workflow components that support subscribing to external events, such as the Dapr Workflow engine, you can use the following "raise event" API to deliver a named event to a specific workflow instance. ``` POST http://localhost:3500/v1.0/workflows///raiseEvent/ ``` {{% alert title="Note" color="primary" %}} The exact mechanism for subscribing to an event depends on the workflow component that you're using. Dapr Workflow has one way of subscribing to external events but other workflow components might have different ways. {{% /alert %}} ### URL parameters Parameter | Description --------- | ----------- `workflowComponentName` | Use `dapr` for Dapr Workflows `instanceId` | Unique value created for each run of a specific workflow `eventName` | The name of the event to raise ### HTTP response codes Code | Description ---- | ----------- `202` | Accepted `400` | Request was malformed `500` | Request formatted correctly, error in dapr code or underlying component ### Response content None. ## Pause workflow request Pause a running workflow instance. ``` POST http://localhost:3500/v1.0/workflows///pause ``` ### URL parameters Parameter | Description --------- | ----------- `workflowComponentName` | Use `dapr` for Dapr Workflows `instanceId` | Unique value created for each run of a specific workflow ### HTTP response codes Code | Description ---- | ----------- `202` | Accepted `400` | Request was malformed `500` | Error in Dapr code or underlying component ### Response content None. ## Resume workflow request Resume a paused workflow instance. ``` POST http://localhost:3500/v1.0/workflows///resume ``` ### URL parameters Parameter | Description --------- | ----------- `workflowComponentName` | Use `dapr` for Dapr Workflows `instanceId` | Unique value created for each run of a specific workflow ### HTTP response codes Code | Description ---- | ----------- `202` | Accepted `400` | Request was malformed `500` | Error in Dapr code or underlying component ### Response content None. ## Purge workflow request Purge the workflow state from your state store with the workflow's instance ID. ``` POST http://localhost:3500/v1.0/workflows///purge ``` {{% alert title="Note" color="primary" %}} Only `COMPLETED`, `FAILED`, or `TERMINATED` workflows can be purged. {{% /alert %}} ### URL parameters Parameter | Description --------- | ----------- `workflowComponentName` | Use `dapr` for Dapr Workflows `instanceId` | Unique value created for each run of a specific workflow ### HTTP response codes Code | Description ---- | ----------- `202` | Accepted `400` | Request was malformed `500` | Error in Dapr code or underlying component ### Response content None. ## Get workflow request Get information about a given workflow instance. ``` GET http://localhost:3500/v1.0/workflows// ``` ### URL parameters Parameter | Description --------- | ----------- `workflowComponentName` | Use `dapr` for Dapr Workflows `instanceId` | Unique value created for each run of a specific workflow ### HTTP response codes Code | Description ---- | ----------- `200` | OK `400` | Request was malformed `500` | Request formatted correctly, error in dapr code or underlying component ### Response content The API call will provide a JSON response similar to this: ```json {   "createdAt": "2023-01-12T21:31:13Z",   "instanceID": "12345678", "lastUpdatedAt": "2023-01-12T21:31:13Z",   "properties": { "property1": "value1", "property2": "value2", }, "runtimeStatus": "RUNNING", } ``` Parameter | Description --------- | ----------- `runtimeStatus` | The status of the workflow instance. Values include: `"RUNNING"`, `"COMPLETED"`, `"CONTINUED_AS_NEW"`, `"FAILED"`, `"CANCELED"`, `"TERMINATED"`, `"PENDING"`, `"SUSPENDED"` ## Component format A Dapr `workflow.yaml` component file has the following structure: ```yaml apiVersion: dapr.io/v1alpha1 kind: Component metadata: name: spec: type: workflow. version: v1.0-alpha1 metadata: - name: value: ``` | Setting | Description | | ------- | ----------- | | `metadata.name` | The name of the workflow component. | | `spec/metadata` | Additional metadata parameters specified by workflow component | However, Dapr comes with a built-in `dapr` workflow component that is built on Dapr Actors. No component file is required to use the built-in Dapr workflow component. ## Next Steps - [Workflow API overview]({{< ref workflow-overview.md >}}) - [Route user to workflow patterns ]({{< ref workflow-patterns.md >}})