YouTube Search Channel and Subscribe

arazzo: 1.0.1
info:
  title: YouTube Search Channel and Subscribe
  summary: Search for a channel, confirm it exists, then subscribe the authenticated user to it.
  description: >-
    A discover-then-act flow. It searches YouTube restricted to channel
    resources, confirms the top result by reading the channel resource, and then
    subscribes the authenticated user to that channel. Every step spells out its
    request inline so the flow can be read and executed without opening the
    underlying OpenAPI description.
  version: 1.0.0
sourceDescriptions:
- name: channelsApi
  url: ../openapi/youtube-channels-api-openapi.yml
  type: openapi
- name: searchApi
  url: ../openapi/youtube-search-api-openapi.yml
  type: openapi
- name: subscriptionsApi
  url: ../openapi/youtube-subscriptions-api-openapi.yml
  type: openapi
workflows:
- workflowId: search-channel-subscribe
  summary: Find a channel by query and subscribe to it.
  description: >-
    Searches for channels matching a query, resolves the first result to a full
    channel resource, and creates a subscription to that channel for the
    authenticated user.
  inputs:
    type: object
    required:
    - apiKey
    - query
    properties:
      apiKey:
        type: string
        description: The Google API key used to authorize each YouTube Data API request.
      query:
        type: string
        description: The query term used to find a channel.
  steps:
  - stepId: searchChannel
    description: Search YouTube restricted to channel resources and capture the first channel id.
    operationId: youtube.search.list
    parameters:
    - name: part
      in: query
      value: snippet
    - name: q
      in: query
      value: $inputs.query
    - name: type
      in: query
      value: channel
    - name: maxResults
      in: query
      value: 5
    - name: key
      in: query
      value: $inputs.apiKey
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      channelId: $response.body#/items/0/id/channelId
  - stepId: getChannel
    description: Read the channel resource to confirm it exists before subscribing.
    operationId: youtube.channels.list
    parameters:
    - name: part
      in: query
      value: snippet,statistics
    - name: id
      in: query
      value: $steps.searchChannel.outputs.channelId
    - name: key
      in: query
      value: $inputs.apiKey
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      channelTitle: $response.body#/items/0/snippet/title
  - stepId: subscribe
    description: Subscribe the authenticated user to the confirmed channel.
    operationId: youtube.subscriptions.insert
    parameters:
    - name: part
      in: query
      value: snippet
    - name: key
      in: query
      value: $inputs.apiKey
    requestBody:
      contentType: application/json
      payload:
        snippet:
          resourceId:
            kind: youtube#channel
            channelId: $steps.searchChannel.outputs.channelId
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      subscriptionId: $response.body#/id
  outputs:
    channelId: $steps.searchChannel.outputs.channelId
    channelTitle: $steps.getChannel.outputs.channelTitle
    subscriptionId: $steps.subscribe.outputs.subscriptionId