openapi: 3.1.0
info:
  title: Dresden Open Data (OGC API Features)
  version: "2026-10-08"
  summary: Geodata of the City of Dresden, including transit lines and stops.
  description: |
    The City of Dresden publishes its geodata through an
    [OGC API Features](https://ogcapi.ogc.org/features/) server. This
    document covers only the parts used by the transit datasets described in
    the Markdown docs. The server itself publishes an OpenAPI document at
    `https://kommisdd.dresden.de/net4/public/ogcapi/Api`, but that one
    only describes the landing page, conformance and collection list, not
    the feature endpoints.

    Server behavior that differs from the OGC defaults (checked on the date
    in the version field):

    - Without `limit`, `items` returns all features of a collection.
    - `offset` is not supported and returns an error.
    - Filtering by property values is not supported; unknown query
      parameters are ignored.
    - Responses have no `next` links and no `numberMatched`.
    - Errors such as an unknown collection or an unsupported parameter come
      back with HTTP 200 and a `{code, description}` JSON object.

    The server sends `Access-Control-Allow-Origin: *`.

    **License:** Open Data license of the City of Dresden. Attribution
    "Landeshauptstadt Dresden" is required; commercial use is permitted.
  contact:
    name: kiliankoe/vvo
    url: https://github.com/kiliankoe/vvo
externalDocs:
  description: Dresden Open Data documentation (Markdown)
  url: https://github.com/kiliankoe/vvo/blob/main/documentation/opendata.md
servers:
  - url: https://kommisdd.dresden.de/net4/public/ogcapi
# No authentication.
security: []
tags:
  - name: Collections
    description: Dataset metadata.
  - name: Features
    description: Dataset contents as GeoJSON.

paths:
  /collections:
    get:
      tags: [Collections]
      operationId: getCollections
      summary: List collections
      description: List all datasets (several hundred). Transit datasets are listed in the Markdown docs.
      parameters:
        - name: f
          in: query
          schema: { type: string, enum: [json] }
          example: json
          description: Response format. Use `json`; browsers otherwise get HTML.
      responses:
        "200":
          description: Collections.
          content:
            application/json:
              schema:
                $ref: "#/components/schemas/Collections"

  /collections/{collectionId}:
    get:
      tags: [Collections]
      operationId: describeCollection
      summary: Describe a collection
      description: Metadata of one dataset, including its attribute names and types.
      parameters:
        - $ref: "#/components/parameters/collectionId"
        - name: f
          in: query
          schema: { type: string, enum: [json] }
          example: json
      responses:
        "200":
          description: Collection metadata.
          content:
            application/json:
              schema:
                oneOf:
                  - $ref: "#/components/schemas/Collection"
                  - $ref: "#/components/schemas/Error"
              example:
                id: L457
                title: Straßenbahnlinien
                links:
                  - rel: items
                    type: application/geo+json
                    title: Datenabruf der Ebene
                    href: https://kommisdd.dresden.de/net4/public/ogcapi/collections/L457/items?limit=10
                extent:
                  spatial:
                    bbox:
                      - [399652.9748, 5650402.6549, 419770.487, 5668600.1244]
                    crs: http://www.opengis.net/def/crs/EPSG/0/25833
                crs:
                  - http://www.opengis.net/def/crs/EPSG/0/4326
                  - http://www.opengis.net/def/crs/EPSG/0/25833
                itemType: feature
                properties:
                  - name: objectid
                    type: Int64
                    flags: RowId, UniqueValues
                  - { name: slinie, type: Text }
                  - { name: takt, type: Double }

  /collections/{collectionId}/items:
    get:
      tags: [Features]
      operationId: getFeatures
      summary: Get features
      description: Features of a dataset as a GeoJSON FeatureCollection.
      parameters:
        - $ref: "#/components/parameters/collectionId"
        - name: limit
          in: query
          schema: { type: integer, minimum: 1 }
          example: 10
          description: Maximum number of features. Without it, all features are returned.
        - name: bbox
          in: query
          style: form
          explode: false
          schema:
            type: array
            items: { type: number }
            minItems: 4
            maxItems: 4
          example: [13.6, 50.9, 13.9, 51.2]
          description: Bounding box as `minLon,minLat,maxLon,maxLat` in WGS84.
        - $ref: "#/components/parameters/crs"
      responses:
        "200":
          description: |
            Features as GeoJSON. Errors such as an unknown collection or an
            unsupported parameter also use HTTP 200, with an error object
            served as `application/json`.
          content:
            application/geo+json:
              schema:
                $ref: "#/components/schemas/FeatureCollection"
              example:
                type: FeatureCollection
                links:
                  - rel: self
                    type: application/json
                    title: Dieses Dokument
                    href: https://kommisdd.dresden.de/net4/public/ogcapi/collections/L1087/items?limit=1
                timeStamp: "2026-10-08T13:14:55.2497994Z"
                numberReturned: 1
                features:
                  - type: Feature
                    geometry:
                      type: Point
                      crs:
                        type: name
                        properties: { name: "urn:ogc:def:crs:EPSG::4326" }
                      coordinates: [13.734074895146318, 51.0510715460776]
                    id: L900.0
                    properties:
                      url: https://www.dvb.de/de-de/service/service-standorte/#kuz
                      x: 5411371.23
                      y: 5658084.27
                      id: 1
                      art: Kundenzentrum
                      name0: DVB-Kundenzentrum
                      aenddat: 15.10.2019 00:00:00
            application/json:
              schema:
                $ref: "#/components/schemas/Error"
              example:
                code: NotImplementedException
                description: Der Parameter 'offset' wird z. Z. nicht unterstützt.

  /collections/{collectionId}/items/{featureId}:
    get:
      tags: [Features]
      operationId: getFeature
      summary: Get a feature
      description: |
        A single feature. Lookup works for numeric feature IDs (pass them
        without the `.0` suffix) but not for string IDs such as `L900.0`.
      parameters:
        - $ref: "#/components/parameters/collectionId"
        - name: featureId
          in: path
          required: true
          schema: { type: string }
          example: "1"
        - $ref: "#/components/parameters/crs"
      responses:
        "200":
          description: Feature.
          content:
            application/geo+json:
              schema:
                $ref: "#/components/schemas/Feature"
        "404":
          description: Feature not found. The body is an empty JSON object.
          content:
            application/geo+json:
              schema:
                type: object

components:
  parameters:
    collectionId:
      name: collectionId
      in: path
      required: true
      schema: { type: string }
      example: L457
      description: |
        Dataset ID. Transit datasets include `L457` (tram lines), `L1076`
        (bus lines), `L1233` (stops with accessibility data) and `L1087` (DVB
        service points).
    crs:
      name: crs
      in: query
      schema:
        type: string
        enum:
          - http://www.opengis.net/def/crs/EPSG/0/4326
          - http://www.opengis.net/def/crs/EPSG/0/25833
        default: http://www.opengis.net/def/crs/EPSG/0/4326
      description: Coordinate reference system of the returned geometries.

  schemas:
    Error:
      type: object
      required: [code]
      properties:
        code:
          type: string
          examples: [NotImplementedException, Exception]
        description:
          type: string

    Link:
      type: object
      required: [href]
      properties:
        href: { type: string }
        rel: { type: string }
        type: { type: string }
        title: { type: string }

    Collection:
      type: object
      required: [id]
      properties:
        id:
          type: string
        title:
          type: string
        description:
          type: [string, "null"]
        links:
          type: array
          items:
            $ref: "#/components/schemas/Link"
        extent:
          type: object
        crs:
          type: array
          items: { type: string }
        itemType:
          type: string
        properties:
          type: array
          description: Attribute names and types. Not part of the OGC standard.
          items:
            type: object
            properties:
              name: { type: string }
              type: { type: string }
              flags: { type: string }

    Collections:
      type: object
      required: [collections]
      properties:
        links:
          type: array
          items:
            $ref: "#/components/schemas/Link"
        collections:
          type: array
          items:
            $ref: "#/components/schemas/Collection"

    Geometry:
      type: object
      description: GeoJSON geometry. Includes a legacy `crs` member naming the coordinate system.
      required: [type]
      properties:
        type:
          type: string
          enum:
            - Point
            - MultiPoint
            - LineString
            - MultiLineString
            - Polygon
            - MultiPolygon
        coordinates:
          type: array
          items: {}
        crs:
          type: object

    Feature:
      type: object
      required: [type, properties]
      properties:
        type:
          const: Feature
        id:
          type: [number, string]
          description: Numeric for most datasets, a string like `L900.0` for some.
        geometry:
          oneOf:
            - $ref: "#/components/schemas/Geometry"
            - type: "null"
        properties:
          type: object
          description: Dataset-specific attributes.

    FeatureCollection:
      type: object
      required: [type, features]
      properties:
        type:
          const: FeatureCollection
        links:
          type: array
          items:
            $ref: "#/components/schemas/Link"
        timeStamp:
          type: string
          format: date-time
        numberReturned:
          type: integer
        features:
          type: array
          items:
            $ref: "#/components/schemas/Feature"