Last.fm Track Radio Seed

arazzo: 1.0.1
info:
  title: Last.fm Track Radio Seed
  summary: Search for a track, resolve its full info, and build a similar-tracks radio seed — branching when no match is found.
  description: >-
    A radio-seeding flow that turns a free-text track query into a list of
    similar tracks. It searches the catalog for a track, branches on whether a
    match was returned, resolves the best match's full info, and then pulls
    tracks similar to it to seed a radio queue. Every request is written inline,
    including the required api_key and the format=json selector, so the chain is
    readable and replayable without the OpenAPI source.
  version: 1.0.0
sourceDescriptions:
- name: trackApi
  url: ../openapi/lastfm-track-api-openapi.yml
  type: openapi
workflows:
- workflowId: track-radio-seed
  summary: Resolve a searched track into a similar-tracks radio seed, branching on no match.
  description: >-
    Searches for a track, branches when there is no match, resolves the best
    match's info, and builds a similar-tracks list.
  inputs:
    type: object
    required:
    - apiKey
    - track
    properties:
      apiKey:
        type: string
        description: Your Last.fm API key.
      track:
        type: string
        description: The track name to search for.
      artist:
        type: string
        description: Optional artist name to narrow the search.
      limit:
        type: integer
        description: Max items per page for the similar tracks list.
        default: 20
  steps:
  - stepId: searchTrack
    description: >-
      Search the catalog for tracks matching the supplied name, narrowed by
      artist when provided.
    operationId: trackSearch
    parameters:
    - name: api_key
      in: query
      value: $inputs.apiKey
    - name: format
      in: query
      value: json
    - name: track
      in: query
      value: $inputs.track
    - name: artist
      in: query
      value: $inputs.artist
    - name: limit
      in: query
      value: 5
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      matchName: $response.body#/results/trackmatches/track/0/name
      matchArtist: $response.body#/results/trackmatches/track/0/artist
    onSuccess:
    - name: hasMatch
      type: goto
      stepId: trackInfo
      criteria:
      - context: $response.body
        condition: $.results.trackmatches.track.length > 0
        type: jsonpath
    - name: noMatch
      type: end
      criteria:
      - context: $response.body
        condition: $.results.trackmatches.track.length == 0
        type: jsonpath
  - stepId: trackInfo
    description: >-
      Resolve the full info envelope for the best matching track.
    operationId: trackGetInfo
    parameters:
    - name: api_key
      in: query
      value: $inputs.apiKey
    - name: format
      in: query
      value: json
    - name: artist
      in: query
      value: $steps.searchTrack.outputs.matchArtist
    - name: track
      in: query
      value: $steps.searchTrack.outputs.matchName
    - name: autocorrect
      in: query
      value: 1
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      trackName: $response.body#/track/name
      trackArtist: $response.body#/track/artist/name
      trackUrl: $response.body#/track/url
  - stepId: similarTracks
    description: >-
      Pull tracks similar to the resolved track to seed a radio queue.
    operationId: trackGetSimilar
    parameters:
    - name: api_key
      in: query
      value: $inputs.apiKey
    - name: format
      in: query
      value: json
    - name: artist
      in: query
      value: $steps.trackInfo.outputs.trackArtist
    - name: track
      in: query
      value: $steps.trackInfo.outputs.trackName
    - name: limit
      in: query
      value: $inputs.limit
    - name: autocorrect
      in: query
      value: 1
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      similarTracks: $response.body#/similartracks/track
  outputs:
    trackName: $steps.trackInfo.outputs.trackName
    trackArtist: $steps.trackInfo.outputs.trackArtist
    trackUrl: $steps.trackInfo.outputs.trackUrl
    similarTracks: $steps.similarTracks.outputs.similarTracks