formats: [oas3]
rules:
  tu-dresden-info-title:
    description: API must declare a title (LOD API).
    severity: error
    given: $.info
    then:
      field: title
      function: truthy
  tu-dresden-info-version:
    description: API must declare a version.
    severity: error
    given: $.info
    then:
      field: version
      function: truthy
  tu-dresden-server-defined:
    description: A server URL should be defined (https://data.slub-dresden.de).
    severity: error
    given: $.servers
    then:
      function: truthy
  tu-dresden-operation-tags:
    description: Every operation should carry at least one tag (source, authority_search, search and access, reconcile, explorative search).
    severity: warn
    given: $.paths[*][get,post]
    then:
      field: tags
      function: truthy
  tu-dresden-operation-operationId:
    description: Every operation must declare a unique operationId.
    severity: error
    given: $.paths[*][get,post]
    then:
      field: operationId
      function: truthy
  tu-dresden-format-param:
    description: Search and access operations expose a 'format' query parameter for content negotiation (nt, rdf, ttl, nq, jsonl, json).
    severity: hint
    given: $.paths[*][get].parameters[?(@.name=='format')]
    then:
      field: schema.type
      function: truthy
  tu-dresden-200-response:
    description: Every operation should document a 200 Success response.
    severity: warn
    given: $.paths[*][get,post].responses
    then:
      field: "200"
      function: truthy