OpenProject Collections API

openapi: 3.1.2
info:
  description: "You're looking at the current **stable** documentation of the OpenProject APIv3. If you're interested in the current\ndevelopment version, please go to [github.com/opf](https://github.com/opf/openproject/tree/dev/docs/api/apiv3).\n\n## Introduction\n\nThe documentation for the APIv3 is written according to the [OpenAPI 3.1 Specification](https://swagger.io/specification/).\nYou can either view the static version of this documentation on the [website](https://www.openproject.org/docs/api/introduction/)\nor the interactive version, rendered with [OpenAPI Explorer](https://github.com/Rhosys/openapi-explorer/blob/main/README.md),\nin your OpenProject installation under `/api/docs`.\nIn the latter you can try out the various API endpoints directly interacting with our OpenProject data.\nMoreover you can access the specification source itself under `/api/v3/spec.json` and `/api/v3/spec.yml`\n(e.g. [here](https://community.openproject.org/api/v3/spec.yml)).\n\nThe APIv3 is a hypermedia REST API, a shorthand for \"Hypermedia As The Engine Of Application State\" (HATEOAS).\nThis means that each endpoint of this API will have links to other resources or actions defined in the resulting body.\n\nThese related resources and actions for any given resource will be context sensitive. For example, only actions that the\nauthenticated user can take are being rendered. This can be used to dynamically identify actions that the user might take for any\ngiven response.\n\nAs an example, if you fetch a work package through the [Work Package endpoint](https://www.openproject.org/docs/api/endpoints/work-packages/), the `update` link will only\nbe present when the user you authenticated has been granted a permission to update the work package in the assigned project.\n\n## HAL+JSON\n\nHAL is a simple format that gives a consistent and easy way to hyperlink between resources in your API.\nRead more in the following specification: [https://tools.ietf.org/html/draft-kelly-json-hal-08](https://tools.ietf.org/html/draft-kelly-json-hal-08)\n\n**OpenProject API implementation of HAL+JSON format** enriches JSON and introduces a few meta properties:\n\n- `_type` - specifies the type of the resource (e.g.: WorkPackage, Project)\n- `_links` - contains all related resource and action links available for the resource\n- `_embedded` - contains all embedded objects\n\nHAL does not guarantee that embedded resources are embedded in their full representation, they might as well be\npartially represented (e.g. some properties can be left out).\nHowever in this API you have the guarantee that whenever a resource is **embedded**, it is embedded in its **full representation**.\n\n## API response structure\n\nAll API responses contain a single HAL+JSON object, even collections of objects are technically represented by\na single HAL+JSON object that itself contains its members. More details on collections can be found\nin the [Collections Section](https://www.openproject.org/docs/api/collections/).\n\n## Authentication\n\nThe API supports the following authentication schemes:\n\n* Session-based authentication\n* API tokens\n    * passed as Bearer token\n    * passed via Basic auth\n* OAuth 2.0\n    * using built-in authorization server\n    * using an external authorization server (RFC 9068)\n\nDepending on the settings of the OpenProject instance many resources can be accessed without being authenticated.\nIn case the instance requires authentication on all requests the client will receive an **HTTP 401** status code\nin response to any request.\n\nOtherwise unauthenticated clients have all the permissions of the anonymous user.\n\n### Session-based authentication\n\nThis means you have to login to OpenProject via the Web-Interface to be authenticated in the API.\nThis method is well-suited for clients acting within the browser, like the Angular-Client built into OpenProject.\n\nIn this case, you always need to pass the HTTP header `X-Requested-With \"XMLHttpRequest\"` for authentication.\n\n### API token as bearer token\n\nUsers can authenticate towards the API v3 using an API token as a bearer token.\n\nFor example:\n\n```shell\nAPI_KEY=opapi-2519132cdf62dcf5a66fd96394672079f9e9cad1\ncurl -H \"Authorization: Bearer $API_KEY\" https://community.openproject.org/api/v3/users/42\n```\n\nUsers can generate API tokens on their account page.\n\n### API token through Basic Auth\n\nAPI tokens can also be used with basic auth, using the user name `apikey` (NOT your login) and the API token as the password.\n\nFor example:\n\n```shell\nAPI_KEY=opapi-2519132cdf62dcf5a66fd96394672079f9e9cad1\ncurl -u apikey:$API_KEY https://community.openproject.org/api/v3/users/42\n```\n\n### OAuth 2.0 authentication\n\nOpenProject allows authentication and authorization with OAuth2 with *Authorization code flow*, as well as *Client credentials* operation modes.\n\nTo get started, you first need to register an application in the OpenProject OAuth administration section of your installation.\nThis will save an entry for your application with a client unique identifier (`client_id`) and an accompanying secret key (`client_secret`).\n\nYou can then use one the following guides to perform the supported OAuth 2.0 flows:\n\n- [Authorization code flow](https://oauth.net/2/grant-types/authorization-code)\n\n- [Authorization code flow with PKCE](https://doorkeeper.gitbook.io/guides/ruby-on-rails/pkce-flow), recommended for clients unable to keep the client_secret confidential\n\n- [Client credentials](https://oauth.net/2/grant-types/client-credentials/) - Requires an application to be bound to an impersonating user for non-public access\n\n### OAuth 2.0 using an external authorization server\n\nThere is a possibility to use JSON Web Tokens (JWT) generated by an OIDC provider configured in OpenProject as a bearer token to do authenticated requests against the API.\nThe following requirements must be met:\n\n- OIDC provider must be configured in OpenProject with **jwks_uri**\n- JWT must be signed using RSA algorithm\n- JWT **iss** claim must be equal to OIDC provider **issuer**\n- JWT **aud** claim must contain the OpenProject **client ID** used at the OIDC provider\n- JWT **scope** claim must include a valid scope to access the desired API (e.g. `api_v3` for APIv3)\n- JWT must be actual (neither expired or too early to be used)\n- JWT must be passed in Authorization header like: `Authorization: Bearer {jwt}`\n- User from **sub** claim must be linked to OpenProject before (e.g. by logging in), otherwise it will be not authenticated\n\nIn more general terms, OpenProject should be compliant to [RFC 9068](https://www.rfc-editor.org/rfc/rfc9068) when validating access tokens.\n\n### Why not username and password?\n\nThe simplest way to do basic auth would be to use a user's username and password naturally.\nHowever, OpenProject already has supported API keys in the past for the API v2, though not through basic auth.\n\nUsing **username and password** directly would have some advantages:\n\n* It is intuitive for the user who then just has to provide those just as they would when logging into OpenProject.\n\n* No extra logic for token management necessary.\n\nOn the other hand using **API keys** has some advantages too, which is why we went for that:\n\n* If compromised while saved on an insecure client the user only has to regenerate the API key instead of changing their password, too.\n\n* They are naturally long and random which makes them invulnerable to dictionary attacks and harder to crack in general.\n\nMost importantly users may not actually have a password to begin with. Specifically when they have registered\nthrough an OpenID Connect provider.\n\n## Cross-Origin Resource Sharing (CORS)\n\nBy default, the OpenProject API is _not_ responding with any CORS headers.\nIf you want to allow cross-domain AJAX calls against your OpenProject instance, you need to enable CORS headers being returned.\n\nPlease see [our API settings documentation](https://www.openproject.org/docs/system-admin-guide/api-and-webhooks/) on\nhow to selectively enable CORS.\n\n## Allowed HTTP methods\n\n- `GET` - Get a single resource or collection of resources\n\n- `POST` - Create a new resource or perform\n\n- `PATCH` - Update a resource\n\n- `DELETE` - Delete a resource\n\n## Compression\n\nResponses are compressed if requested by the client. Currently [gzip](https://www.gzip.org/) and [deflate](https://tools.ietf.org/html/rfc1951)\nare supported. The client signals the desired compression by setting the [`Accept-Encoding` header](https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.3).\nIf no `Accept-Encoding` header is send, `Accept-Encoding: identity` is assumed which will result in the API responding uncompressed."
  title: OpenProject API V3 (Stable) Actions & Capabilities Collections 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: 'Whenever a client calls a resource that can return more than one element, it will receive a collection of elements.

    However as collections can become quite large, the API will **not** simply return a JSON array, but a special collection

    object that will contain the actual elements in its embedded property `elements`.


    Collections *may* be paginated, this means that a single response from the server will not contain all elements of the collection,

    but only a subset. In this case the client can issue further requests to retrieve the remaining elements.

    There are two ways to access the result pages of a paginated collection:


    * offset based pagination


    * cursor based pagination


    The available ways of pagination depend on the collection queried. Some collections feature no pagination at all, meaning they

    will always return all elements. Others might only offer one of the two pagination methods or both of them.


    A collection also carries meta information like the total count of elements in the collection or - in case of a paginated collection -

    the amount of elements returned in this response and action links to retrieve the remaining elements.


    ## Local Properties


    | Property | Description                                                     | Type    | Availability                |

    |:--------:| --------------------------------------------------------------- | ------- | --------------------------- |

    | total    | The total amount of elements available in the collection        | Integer | always                      |

    | pageSize | Amount of elements that a response will hold                    | Integer | when paginated              |

    | count    | Actual amount of elements in this response                      | Integer | always                      |

    | offset   | The page number that is requested from paginated collection     | Integer | when offset based available |

    | groups   | Summarized information about aggregation groups                 | Object  | when grouping               |

    | totalSums| Aggregations of supported values for elements of the collection | Object  | when showing sums           |


    ## Links


    | Link             | Description                                                              | Availability                |

    |:----------------:| ------------------------------------------------------------------------ | --------------------------- |

    | self             | Link to the current page in the collection                               | always                      |

    | changeSize       | Templated link to change the page size, might change relative position   | when paginated              |

    | jumpTo           | Templated link to jump to a specified offset                             | when offset based available |

    | nextByOffset     | Link to retrieve the following page of elements (offset based)           | when offset based available |

    | previousByOffset | Link to retrieve the preceding page of elements (offset based)           | when offset based available |

    | nextByCursor     | Link to retrieve the elements following the current page (cursor based)  | when cursor based available |

    | previousByCursor | Link to retrieve the elements preceding the current page (cursor based)  | when cursor based available |'
  name: Collections
paths:
  /api/v3/examples:
    get:
      parameters:
      - description: 'The column to group by.

          Note: Aggregation is as of now only supported by the work package collection.

          You can pass any column name as returned by the [queries](https://www.openproject.org/docs/api/endpoints/queries/) endpoint.'
        example: status
        in: query
        name: groupBy
        required: false
        schema:
          type: string
      - description: ''
        example: true
        in: query
        name: showSums
        required: false
        schema:
          default: false
          type: boolean
      responses:
        '200':
          description: OK
          headers: {}
      tags:
      - Collections
      description: ''
      operationId: view_aggregated_result
      summary: view aggregated result
components:
  securitySchemes:
    BasicAuth:
      type: http
      scheme: basic