# OpenProject Relations API

**Canonical:** https://apis.io/apis/openproject/openproject-relations-api/  
**Provider:** OpenProject — https://apis.io/providers/openproject/  
**Base URL:** https://community.openproject.org/api/v3  
**Documentation:** https://www.openproject.org/docs/api/

OpenProject Relations API is one of 62 APIs that [OpenProject](https://apis.io/providers/openproject/) publishes on the [APIs.io](https://apis.io/) network, described by a machine-readable OpenAPI specification. Tagged areas include Relations. The published artifact set on APIs.io includes an OpenAPI specification and API documentation.

Work packages may be related to each other in different ways. ``` +--------------+ +--------------+ | | 1 1 | | | Work package +-------------+--------------+ Work package | | | from | to | | +--------------+ | +--------------+ +------+-------+ | Relation | +--------------+ | type | | reverseType | | description | | lag | +--------------+ ``` ## Actions | Link | Description | Condition | |:-------------------:| -------------------------------------------------------------------- | --------------------------------------------- | | update | Updates the relation between two work packages via a form | **Permission**: manage work package relations | | updateImmediately | Updates the relation between two work packages | **Permission**: manage work package relations | | delete | Destroys the relation between the two work packages | **Permission**: manage work package relations | ## Linked Properties | Link | Description | Type | Constraints | Supported operations | Condition | |:-------------:|-------------------------------------- | ------------- | ----------- | -------------------- | --------------------------------------------- | | self | This relation | Relation | not null | READ | **Permission**: view work packages | | schema | The schema of this relation | Schema | not null | READ | | | from | The emanating work package | WorkPackage | not null | READ | **Permission**: view work packages | | to | The work package the relation ends in | WorkPackage | not null | READ | **Permission**: view work packages | ## Local Properties | Property | Description | Type | Constraints | Supported operations | | :---------------:| ------------------------------------------------------------- | ------- | ------------------------------------------------------------------------------------------------------------- | -------------------- | | id | Relation ID | Integer | x > 0 | READ | | name | The internationalized name of this kind of relation | String | | READ | type | Which kind of relation (blocks, precedes, etc.) | String | in: relates, duplicates, duplicated, blocks, blocked, precedes, follows, includes, partof, requires, required | READ / WRITE | | reverseType | The kind of relation from the other WP's perspective | String | in: relates, duplicates, duplicated, blocks, blocked, precedes, follows, includes, partof, requires, required | READ | | description | Short text further describing the relation | String | | READ / WRITE | | lag* | The number of days between closing of `from` and start of `to`| Integer | x >= 0 | READ / WRITE | \* Only applicable for some relation types such as "follows". You can check using the relation by schema endpoint at `/api/v3/relations/schema/{type}`.

## Machine-readable artifacts (5)

- **OpenAPI** — https://raw.githubusercontent.com/api-evangelist/openproject/refs/heads/main/openapi/openproject-relations-api-openapi.yml
- **Documentation** — https://www.openproject.org/docs/api/
- **Introduction** — https://www.openproject.org/docs/api/introduction/
- **Endpoints** — https://www.openproject.org/docs/api/endpoints/
- **GitHub** — https://github.com/opf/openproject

## Other OpenProject APIs (12)

- [OpenProject Actions & Capabilities API](https://apis.io/apis/openproject/openproject-actions-capabilities-api/)
- [OpenProject Activities API](https://apis.io/apis/openproject/openproject-activities-api/)
- [OpenProject Attachments API](https://apis.io/apis/openproject/openproject-attachments-api/)
- [OpenProject Budgets API](https://apis.io/apis/openproject/openproject-budgets-api/)
- [OpenProject Categories API](https://apis.io/apis/openproject/openproject-categories-api/)
- [OpenProject Collections API](https://apis.io/apis/openproject/openproject-collections-api/)
- [OpenProject Configuration API](https://apis.io/apis/openproject/openproject-configuration-api/)
- [OpenProject Custom actions API](https://apis.io/apis/openproject/openproject-custom-actions-api/)
- [OpenProject Custom Field Items API](https://apis.io/apis/openproject/openproject-custom-field-items-api/)
- [OpenProject Custom Fields API](https://apis.io/apis/openproject/openproject-custom-fields-api/)
- [OpenProject Custom Options API](https://apis.io/apis/openproject/openproject-custom-options-api/)
- [OpenProject Documents API](https://apis.io/apis/openproject/openproject-documents-api/)

## Tags

Relations

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/apis/openproject/openproject-relations-api/). The API's provider profile, Kin Score and agent-readiness rating are at https://apis.io/providers/openproject/.