openapi: 3.2.0
info:
  title: 4TU.ResearchData Collections API
  version: v2+v3
  summary: Public read API for the 4TU.ResearchData repository operated by TU Delft Library.
  description: 'Public, unauthenticated read interface to the 4TU.ResearchData repository at https://data.4tu.nl, the science/engineering/design research data repository of the 4TU.Federation. The service runs on `djehuty`, open-source repository software written by 4TU.ResearchData and Nikhef — it is NOT a Figshare, Elsevier Pure, Dataverse or DSpace tenancy. The `/v2` surface is deliberately backward compatible with the Figshare v2 API shape (differences: `uuid` supersedes `id`, and usage errors return precise HTTP codes rather than always 400); `/v3` is djehuty''s own surface. Endpoints under `/v2/account/` and parts of `/v3` require a personal API token.

    OPERATOR NOTE: data.4tu.nl resolves to 131.180.169.22, inside the RIPE `DUNET` inetnum registered to Technische Universiteit Delft, and re3data records TU Delft Library as the hosting institution for the 4TU.Federation consortium (with TU Eindhoven, University of Twente and Wageningen University as the other partners). It is therefore institution-operated infrastructure that is co-owned by a four-university consortium, not a vendor platform.'
  contact:
    name: 4TU.ResearchData
    email: researchdata@4tu.nl
    url: https://data.4tu.nl/info/about-4turesearchdata/contact
  license:
    name: EUPL-1.2 (djehuty software)
    url: https://github.com/4TUResearchData/djehuty/blob/main/LICENSE
  termsOfService: https://data.4tu.nl/info/about-4turesearchdata/policies-guidelines
servers:
- url: https://data.4tu.nl
  description: 4TU.ResearchData production (TU Delft Library operated)
tags:
- name: Collections
  description: Curated groupings of published datasets.
paths:
  /v2/collections:
    get:
      tags:
      - Collections
      operationId: listCollections
      summary: List published collections
      parameters:
      - name: limit
        in: query
        required: false
        schema:
          type: integer
      - name: offset
        in: query
        required: false
        schema:
          type: integer
      responses:
        '200':
          description: A list of collection summaries.
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/CollectionSummary'
  /v2/collections/{uuid}:
    get:
      tags:
      - Collections
      operationId: getCollection
      summary: Get one published collection
      parameters:
      - $ref: '#/components/parameters/Uuid'
      responses:
        '200':
          description: The full collection record.
          content:
            application/json:
              schema:
                type: object
        '404':
          $ref: '#/components/responses/NotFound'
components:
  schemas:
    CollectionSummary:
      type: object
      properties:
        id:
          type:
          - integer
          - 'null'
        uuid:
          type: string
          format: uuid
        title:
          type: string
        doi:
          type: string
        handle:
          type: string
        url:
          type: string
          format: uri
        timeline:
          type: object
        published_date:
          type:
          - string
          - 'null'
    Error:
      type: object
      properties:
        message:
          type: string
        code:
          type: string
  parameters:
    Uuid:
      name: uuid
      in: path
      required: true
      description: The dataset or collection UUID. On this repository `uuid` supersedes the Figshare numeric `id`.
      schema:
        type: string
        format: uuid
  responses:
    NotFound:
      description: The resource does not exist.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
          examples:
            notFound:
              value:
                message: This resource does not exist.
  securitySchemes:
    tokenAuth:
      type: http
      scheme: token
      description: '`Authorization: token YOUR_TOKEN_HERE`. Tokens are issued from the depositor dashboard after logging in; there is no OAuth 2.0 flow and no published scope vocabulary.'
x-artifact:
  generated: '2026-08-19'
  method: derived
  source: Derived from live unauthenticated probes of https://data.4tu.nl on 2026-08-19 (every path, parameter, status code and field name in this document was observed in a real response), cross-read against the djehuty API documentation at https://raw.githubusercontent.com/4TUResearchData/djehuty/main/docs/api.md and https://djehuty.4tu.nl/. 4TU.ResearchData publishes no OpenAPI of its own; the djehuty repository tree contains no openapi/swagger file (checked via the GitHub trees API, 575 entries). This is API Evangelist's derivation, not a 4TU artifact.
  x-operator: institution
  x-operator-evidence: data.4tu.nl -> 131.180.169.22, RIPE inetnum 131.180.0.0/16 netname DUNET, org-name "Technische Universiteit Delft". re3data r3d100010216 lists TU Delft Library as a hosting institution alongside the 4TU.Federation.