OpenProject

OpenProject Categories API

The categories endpoints return collections or single entities of type `Category`. The following tables list the different properties of `Category` entities. ## Linked Properties | Link | Description | Type | Constraints | Supported operations | |:---------------:| --------------------------------------------------- | ------------- | ----------- | -------------------- | | self | This category | Category | not null | READ | | project | The project of this category | Project | not null | READ | | defaultAssignee | Default assignee for work packages of this category | User | | READ | ## Local Properties | Property | Description | Type | Constraints | Supported operations | | :--------: | ------------- | ------- | ----------- | -------------------- | | id | Category id | Integer | x > 0 | READ | | name | Category name | String | | READ |

GitHub OpenAPI

Operations 3

GET /api/v3/categories/{id} View Category #
GET /api/v3/projects/{id}/categories List categories of a project #
GET /api/v3/workspaces/{id}/categories List categories of a workspace #

Documentation

📖
Documentation
https://www.openproject.org/docs/api/

Specifications

⚙
OpenAPI
https://raw.githubusercontent.com/api-evangelist/openproject/refs/heads/main/openapi/openproject-categories-api-openapi.yml

Other Resources

🔗
Introduction
https://www.openproject.org/docs/api/introduction/
🔗
Endpoints
https://www.openproject.org/docs/api/endpoints/
🔗
GitHub
https://github.com/opf/openproject

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OpenAPI Specification

openproject-categories-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  description: You're looking at the current **stable** documentation of the OpenProject APIv3.
  title: OpenProject API V3 (Stable) Categories API
  version: '3'
servers:
- url: https://qa.openproject-edge.com
  description: Edge QA instance
- url: https://qa.openproject-stage.com
  description: Staging instance
- url: https://community.openproject.org
  description: Community instance
security:
- BasicAuth: []
tags:
- description: The categories endpoints return collections or single entities of type `Category`.
  name: Categories
paths:
  /api/v3/categories/{id}:
    get:
      parameters:
      - description: Category id
        example: '1'
        in: path
        name: id
        required: true
        schema:
          type: integer
      responses:
        '200':
          content:
            application/hal+json:
              examples:
                response:
                  value:
                    _links:
                      defaultAssignee:
                        href: /api/v3/users/42
                        title: John Sheppard
                      project:
                        href: /api/v3/projects/11
                        title: Example project
                      self:
                        href: /api/v3/categories/10
                        title: Category with assignee
                    _type: Category
                    id: 10
                    name: Foo
              schema:
                $ref: '#/components/schemas/CategoryModel'
          description: OK
          headers: {}
        '404':
          content:
            application/hal+json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
              examples:
                response:
                  value:
                    _type: Error
                    errorIdentifier: urn:openproject-org:api:v3:errors:NotFound
                    message: The specified category does not exist.
          description: 'Returned if the category does not exist or the client does not have sufficient permissions

            to see it.


            **Required permission:** view project (defining the category)


            *Note: A client without sufficient permissions shall not be able to test for the existence of

            a category. That''s why a 404 is returned here, even if a 403 might be more appropriate.*'
          headers: {}
      tags:
      - Categories
      description: ''
      operationId: View_Category
      summary: View Category
  /api/v3/projects/{id}/categories:
    get:
      parameters:
      - description: ID of the project whose categories will be listed
        example: 1
        in: path
        name: id
        required: true
        schema:
          type: integer
      responses:
        '200':
          content:
            application/hal+json:
              examples:
                response:
                  value:
                    _embedded:
                      elements:
                      - _links:
                          defaultAssignee:
                            href: /api/v3/users/42
                            title: John Sheppard
                          project:
                            href: /api/v3/projects/11
                            title: Example project
                          self:
                            href: /api/v3/categories/10
                            title: Category with assignee
                        _type: Category
                        id: 10
                        name: Foo
                      - _links:
                          project:
                            href: /api/v3/projects/11
                          self:
                            href: /api/v3/categories/11
                        _type: Category
                        id: 11
                        name: Bar
                    _links:
                      self:
                        href: /api/v3/projects/11/categories
                    _type: Collection
                    count: 2
                    total: 2
              schema:
                $ref: '#/components/schemas/Categories_by_WorkspaceModel'
          description: OK
          headers: {}
        '404':
          content:
            application/hal+json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
              examples:
                response:
                  value:
                    _type: Error
                    errorIdentifier: urn:openproject-org:api:v3:errors:NotFound
                    message: The specified project does not exist.
          description: 'Returned if the project does not exist or the client does not have sufficient permissions

            to see it.


            **Required permission:** view project


            *Note: A client without sufficient permissions shall not be able to test for the existence of a project.

            That''s why a 404 is returned here, even if a 403 might be more appropriate.*'
          headers: {}
      tags:
      - Categories
      description: 'List all categories of a project

        This endpoint is deprecated and replaced by `/api/v3/workspaces/{id}/categories`'
      operationId: List_categories_of_a_project
      summary: List categories of a project
  /api/v3/workspaces/{id}/categories:
    get:
      parameters:
      - description: ID of the workspace whose categories will be listed
        example: 1
        in: path
        name: id
        required: true
        schema:
          type: integer
      responses:
        '200':
          content:
            application/hal+json:
              examples:
                response:
                  value:
                    _embedded:
                      elements:
                      - _links:
                          defaultAssignee:
                            href: /api/v3/users/42
                            title: John Sheppard
                          project:
                            href: /api/v3/projects/11
                            title: Example project
                          self:
                            href: /api/v3/categories/10
                            title: Category with assignee
                        _type: Category
                        id: 10
                        name: Foo
                      - _links:
                          project:
                            href: /api/v3/projects/11
                          self:
                            href: /api/v3/categories/11
                        _type: Category
                        id: 11
                        name: Bar
                    _links:
                      self:
                        href: /api/v3/projects/11/categories
                    _type: Collection
                    count: 2
                    total: 2
              schema:
                $ref: '#/components/schemas/Categories_by_WorkspaceModel'
          description: OK
          headers: {}
        '404':
          content:
            application/hal+json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
              examples:
                response:
                  value:
                    _type: Error
                    errorIdentifier: urn:openproject-org:api:v3:errors:NotFound
                    message: The specified project does not exist.
          description: 'Returned if the workspace does not exist or the client does not have sufficient permissions

            to see it.


            **Required permission:** view workspace


            *Note: A client without sufficient permissions shall not be able to test for the existence of a workspace.

            That''s why a 404 is returned here, even if a 403 might be more appropriate.*'
          headers: {}
      tags:
      - Categories
      description: List all categories of a project
      operationId: List_categories_of_a_workspace
      summary: List categories of a workspace
components:
  schemas:
    CollectionLinks:
      type: object
      required:
      - self
      properties:
        self:
          allOf:
          - $ref: '#/components/schemas/Link'
          - description: 'This collection resource.


              **Resource**: Collection'
    Link:
      type: object
      required:
      - href
      properties:
        href:
          type:
          - string
          - 'null'
          description: URL to the referenced resource (might be relative)
        title:
          type: string
          description: Representative label for the resource
        templated:
          type: boolean
          default: false
          description: If true the href contains parts that need to be replaced by the client
        method:
          type: string
          default: GET
          description: The HTTP verb to use when requesting the resource
        payload:
          type: object
          description: The payload to send in the request to achieve the desired result
        identifier:
          type: string
          description: An optional unique identifier to the link object
        type:
          type: string
          description: The MIME-Type of the returned resource.
      example:
        href: /api/v3/work_packages
        method: POST
    Categories_by_WorkspaceModel:
      allOf:
      - $ref: '#/components/schemas/CollectionModel'
      - type: object
        required:
        - _links
        - _embedded
        properties:
          _links:
            type: object
            required:
            - self
            properties:
              self:
                allOf:
                - $ref: '#/components/schemas/Link'
                - description: 'The categories collection


                    **Resource**: CategoriesCollection'
                  readOnly: true
          _embedded:
            type: object
            properties:
              elements:
                type: array
                readOnly: true
                items:
                  allOf:
                  - $ref: '#/components/schemas/CategoryModel'
                  - description: Collection of Categories
    CategoryModel:
      type: object
      properties:
        id:
          type: integer
          description: Category id
          readOnly: true
          exclusiveMinimum: 0
        name:
          type: string
          description: Category name
        _links:
          type: object
          required:
          - self
          - project
          properties:
            self:
              allOf:
              - $ref: '#/components/schemas/Link'
              - description: 'This category


                  **Resource**: Category'
                readOnly: true
            project:
              allOf:
              - $ref: '#/components/schemas/Link'
              - description: 'The project of this category


                  **Resource**: Project'
                readOnly: true
            defaultAssignee:
              allOf:
              - $ref: '#/components/schemas/Link'
              - description: 'Default assignee for work packages of this category


                  **Resource**: User'
                readOnly: true
      example:
        _links:
          self:
            href: /api/v3/categories/10
            title: Category with assignee
          project:
            href: /api/v3/projects/11
            title: Example project
          defaultAssignee:
            href: /api/v3/users/42
            title: John Sheppard
        _type: Category
        id: 10
        name: Foo
    ErrorResponse:
      type: object
      required:
      - _type
      - errorIdentifier
      - message
      properties:
        _embedded:
          type: object
          properties:
            details:
              type: object
              properties:
                attribute:
                  type: string
                  example: project
        _type:
          type: string
          enum:
          - Error
        errorIdentifier:
          type: string
          example: urn:openproject-org:api:v3:errors:PropertyConstraintViolation
        message:
          type: string
          example: Project can't be blank.
    CollectionModel:
      type: object
      required:
      - _type
      - total
      - count
      - _links
      properties:
        _type:
          type: string
          enum:
          - Collection
        total:
          type: integer
          description: The total amount of elements available in the collection.
          minimum: 0
        count:
          type: integer
          description: Actual amount of elements in this response.
          minimum: 0
        _links:
          $ref: '#/components/schemas/CollectionLinks'
  securitySchemes:
    BasicAuth:
      type: http
      scheme: basic