> ## Documentation Index > Fetch the complete documentation index at: https://docs.eorion.com/llms.txt > Use this file to discover all available pages before exploring further. # 通过Id启动实例 > Instantiates a given process definition. Process variables and business key may be supplied in the request body. ## OpenAPI ````yaml POST /process-definition/{id}/start openapi: 3.0.2 info: title: ORION Platform REST API description: OpenApi Spec for ORION Camunda Platform REST API. version: 7.22.6-ee license: name: Apache License 2.0 url: http://www.apache.org/licenses/LICENSE-2.0.html servers: - url: http://{host}:{port}/{contextPath} description: The API server for the default process engine variables: host: default: localhost port: default: '8080' contextPath: default: engine-rest - url: http://{host}:{port}/{contextPath}/engine/{engineName} description: The API server for a named process engine variables: host: default: localhost port: default: '8080' contextPath: default: engine-rest engineName: default: default - url: '{url}' description: The API server with a custom url variables: url: default: '' security: - basicAuth: [] tags: - name: Authorization - name: Batch - name: Condition - name: Decision Definition - name: Decision Requirements Definition - name: Deployment - name: Engine - name: Event Subscription - name: Execution - name: External Task - name: Filter - name: Group - name: Historic Activity Instance - name: Historic Batch - name: Historic Decision Definition - name: Historic Decision Instance - name: Historic Decision Requirements Definition - name: Historic Detail - name: Historic External Task Log - name: Historic Identity Link Log - name: Historic Incident - name: Historic Job Log - name: Historic Process Definition - name: Historic Process Instance - name: Historic Task Instance - name: Historic User Operation Log - name: Historic Variable Instance - name: History Cleanup - name: Identity - name: Incident - name: Job - name: Job Definition - name: Message - name: Metrics - name: Migration - name: Modification - name: Process Definition - name: Process Instance - name: Signal - name: Schema Log - name: Task - name: Task Attachment - name: Task Comment - name: Task Identity Link - name: Task Local Variable - name: Task Variable - name: Telemetry - name: Tenant - name: User - name: Variable Instance - name: Version externalDocs: description: Find out more about ORION Rest API url: https://docs.eorion.com paths: /process-definition/{id}/start: post: tags: - Process Definition summary: Start Instance description: |- Instantiates a given process definition. Process variables and business key may be supplied in the request body. operationId: startProcessInstance parameters: - name: id in: path schema: type: string required: true description: The id of the process definition to be retrieved. requestBody: content: application/json: schema: $ref: '#/components/schemas/StartProcessInstanceDto' examples: example-1: summary: Starting a process instance at its default initial activity value: variables: aVariable: value: aStringValue type: String anotherVariable: value: true type: Boolean businessKey: myBusinessKey example-2: summary: Starting a process instance with variables in return value: variables: aVariable: value: aStringValue type: String anotherVariable: value: true type: Boolean businessKey: myBusinessKey withVariablesInReturn: true example-3: summary: Starting a process instance at two specific activities value: variables: aProcessVariable: value: aStringValue type: String businessKey: myBusinessKey skipCustomListeners: true startInstructions: - type: startBeforeActivity activityId: activityId variables: var: value: aVariableValue local: false type: String - type: startAfterActivity activityId: anotherActivityId variables: varLocal: value: anotherVariableValue local: true type: String responses: '200': content: application/json: schema: $ref: '#/components/schemas/ProcessInstanceWithVariablesDto' examples: example-1: summary: Status 200 Response 1 description: >- Response for starting a process instance at its default initial activity value: links: - method: GET href: http://localhost:8080/rest-test/process-instance/anId rel: self id: anId definitionId: aProcessDefinitionId businessKey: myBusinessKey caseInstanceId: null tenantId: null ended: false suspended: false example-2: summary: Status 200 Response 2 description: >- Response for starting a process instance with variables in return value: links: - method: GET href: >- http://localhost:8080/rest-test/process-instance/aProcInstId rel: self id: aProcInstId definitionId: aProcessDefinitionId businessKey: myBusinessKey caseInstanceId: null ended: false suspended: false tenantId: null variables: anotherVariable: type: Boolean value: true valueInfo: transient: true aVariable: type: String value: aStringValue valueInfo: {} example-3: summary: Status 200 Response 3 description: >- Response for starting a process instance at two specific activities value: links: - method: GET href: http://localhost:8080/rest-test/process-instance/anId rel: self id: anId definitionId: aProcessDefinitionId businessKey: myBusinessKey caseInstanceId: null tenantId: null ended: false suspended: false description: Request successful. '400': content: application/json: schema: $ref: '#/components/schemas/ExceptionDto' description: >- The instance could not be created due to an invalid variable value, for example if the value could not be parsed to an `Integer` value or the passed variable type is not supported. See the [Introduction](https://docs.camunda.org/manual/7.22/reference/rest/overview/#error-handling) for the error response format. '500': content: application/json: schema: $ref: '#/components/schemas/ExceptionDto' description: >- The instance could not be created successfully. See the [Introduction](https://docs.camunda.org/manual/7.22/reference/rest/overview/#error-handling) for the error response format. components: schemas: StartProcessInstanceDto: type: object properties: businessKey: type: string nullable: true description: The business key of the process instance. variables: type: object nullable: true additionalProperties: $ref: '#/components/schemas/VariableValueDto' description: '' caseInstanceId: type: string nullable: true description: The case instance id the process instance is to be initialized with. startInstructions: type: array nullable: true items: $ref: '#/components/schemas/ProcessInstanceModificationInstructionDto' description: >- **Optional**. A JSON array of instructions that specify which activities to start the process instance at. If this property is omitted, the process instance starts at its default blank start event. skipCustomListeners: type: boolean nullable: true description: >- Skip execution listener invocation for activities that are started or ended as part of this request. **Note**: This option is currently only respected when start instructions are submitted via the `startInstructions` property. skipIoMappings: type: boolean nullable: true description: >- Skip execution of [input/output variable mappings](https://docs.camunda.org/manual/7.22/user-guide/process-engine/variables/#input-output-variable-mapping) for activities that are started or ended as part of this request. **Note**: This option is currently only respected when start instructions are submitted via the `startInstructions` property. withVariablesInReturn: type: boolean nullable: true description: >- Indicates if the variables, which was used by the process instance during execution, should be returned. Default value: `false` ProcessInstanceWithVariablesDto: allOf: - type: object properties: variables: type: object nullable: true additionalProperties: $ref: '#/components/schemas/VariableValueDto' description: The id of the process instance. - $ref: '#/components/schemas/ProcessInstanceDto' ExceptionDto: title: ExceptionDto type: object properties: type: type: string nullable: true description: An exception class indicating the occurred error. message: type: string nullable: true description: A detailed message of the error. code: type: number description: >- The code allows your client application to identify the error in an automated fashion. You can look up the meaning of all built-in codes and learn how to add custom codes in the [User Guide](https://docs.camunda.org/manual/7.22/user-guide/process-engine/error-handling/#exception-codes). VariableValueDto: type: object properties: value: $ref: '#/components/schemas/AnyValue' type: type: string nullable: true description: The value type of the variable. valueInfo: type: object additionalProperties: true description: >- A JSON object containing additional, value-type-dependent properties. For serialized variables of type Object, the following properties can be provided: * `objectTypeName`: A string representation of the object's type name. * `serializationDataFormat`: The serialization format used to store the variable. For serialized variables of type File, the following properties can be provided: * `filename`: The name of the file. This is not the variable name but the name that will be used when downloading the file again. * `mimetype`: The MIME type of the file that is being uploaded. * `encoding`: The encoding of the file that is being uploaded. The following property can be provided for all value types: * `transient`: Indicates whether the variable should be transient or not. See [documentation](https://docs.camunda.org/manual/7.22/user-guide/process-engine/variables#transient-variables) for more informations. (Not applicable for `decision-definition`, ` /process-instance/variables-async`, and `/migration/executeAsync` endpoints) ProcessInstanceModificationInstructionDto: type: object required: - type properties: type: type: string enum: - cancel - startBeforeActivity - startAfterActivity - startTransition description: >- **Mandatory**. One of the following values: `cancel`, `startBeforeActivity`, `startAfterActivity`, `startTransition`. * A cancel instruction requests cancellation of a single activity instance or all instances of one activity. * A startBeforeActivity instruction requests to enter a given activity. * A startAfterActivity instruction requests to execute the single outgoing sequence flow of a given activity. * A startTransition instruction requests to execute a specific sequence flow. variables: $ref: '#/components/schemas/TriggerVariableValueDto' activityId: type: string nullable: true description: >- Can be used with instructions of types `startTransition`. Specifies the sequence flow to start. transitionId: type: string nullable: true description: >- Can be used with instructions of types `startTransition`. Specifies the sequence flow to start. activityInstanceId: type: string nullable: true description: >- Can be used with instructions of type `cancel`. Specifies the activity instance to cancel. Valid values are the activity instance IDs supplied by the [Get Activity Instance request](https://docs.camunda.org/manual/7.22/reference/rest/process-instance/get-activity-instances/). transitionInstanceId: type: string nullable: true description: >- Can be used with instructions of type `cancel`. Specifies the transition instance to cancel. Valid values are the transition instance IDs supplied by the [Get Activity Instance request](https://docs.camunda.org/manual/7.22/reference/rest/process-instance/get-activity-instances/). ancestorActivityInstanceId: type: string nullable: true description: >- Can be used with instructions of type `startBeforeActivity`, `startAfterActivity`, and `startTransition`. Valid values are the activity instance IDs supplied by the Get Activity Instance request. If there are multiple parent activity instances of the targeted activity, this specifies the ancestor scope in which hierarchy the activity/transition is to be instantiated. Example: When there are two instances of a subprocess and an activity contained in the subprocess is to be started, this parameter allows to specifiy under which subprocess instance the activity should be started. cancelCurrentActiveActivityInstances: type: boolean nullable: true description: >- Can be used with instructions of type cancel. Prevents the deletion of new created activity instances. ProcessInstanceDto: allOf: - type: object properties: id: type: string nullable: true description: The id of the process instance. definitionId: type: string nullable: true description: >- The id of the process definition that this process instance belongs to. businessKey: type: string nullable: true description: The business key of the process instance. caseInstanceId: type: string nullable: true description: >- The id of the case instance associated with the process instance. ended: type: boolean nullable: true deprecated: true description: >- A flag indicating whether the process instance has ended or not. Deprecated: will always be false! suspended: type: boolean nullable: true description: >- A flag indicating whether the process instance is suspended or not. tenantId: type: string nullable: true description: The tenant id of the process instance. - $ref: '#/components/schemas/LinkableDto' AnyValue: description: |- Can be any value - string, number, boolean, array or object. **Note**: Not every endpoint supports every type. TriggerVariableValueDto: allOf: - type: object properties: local: type: boolean nullable: true description: >- Indicates whether the variable should be a local variable or not. If set to true, the variable becomes a local variable of the execution entering the target activity. - $ref: '#/components/schemas/VariableValueDto' LinkableDto: type: object properties: links: type: array nullable: true items: $ref: '#/components/schemas/AtomLink' description: >- The links associated to this resource, with `method`, `href` and `rel`. AtomLink: type: object properties: rel: type: string nullable: true description: The relation of the link to the object that belongs to. href: type: string nullable: true description: The url of the link. method: type: string nullable: true description: The http method. securitySchemes: basicAuth: type: http scheme: basic ````