extends:
  - spectral:oas

documentationUrl: https://postalcodes.info/api

rules:
  # Provider identity
  postalcodes-info-contact-required:
    description: PostalCodes.info specs must keep contact details for the maintainer.
    message: 'info.contact.email is required and should point to PostalCodes.info maintainer.'
    severity: error
    given: $.info.contact
    then:
      - field: email
        function: truthy
      - field: url
        function: truthy

  postalcodes-info-license-odbl:
    description: PostalCodes.info data is published under the Open Database License (ODbL) 1.0.
    message: 'info.license should reference the Open Database License (ODbL) 1.0.'
    severity: warn
    given: $.info.license
    then:
      - field: name
        function: pattern
        functionOptions:
          match: '(?i)open database license|odbl'
      - field: url
        function: pattern
        functionOptions:
          match: 'opendatacommons\\.org/licenses/odbl'

  postalcodes-info-server-canonical-host:
    description: The canonical server must point at https://postalcodes.info.
    message: 'servers[].url must reference https://postalcodes.info.'
    severity: error
    given: $.servers[*]
    then:
      field: url
      function: pattern
      functionOptions:
        match: '^https://postalcodes\\.info(/.*)?$'

  # Operations and summaries
  postalcodes-info-operation-summary-title-case:
    description: Operation summaries must use Title Case to match the documentation portal.
    message: 'Operation summary "{{value}}" should use Title Case.'
    severity: warn
    given: $.paths.*.*.summary
    then:
      function: pattern
      functionOptions:
        match: '^[A-Z0-9][A-Za-z0-9 ,\\-\\(\\)/]*$'

  postalcodes-info-operation-id-camel:
    description: operationId values should be lowerCamelCase verbs.
    message: 'operationId "{{value}}" should be lowerCamelCase.'
    severity: warn
    given: $.paths.*.*.operationId
    then:
      function: pattern
      functionOptions:
        match: '^[a-z][a-zA-Z0-9]+$'

  postalcodes-info-operation-tags-allowed:
    description: Only Search, Downloads and Lookup Pages tags are sanctioned for postalcodes.info paths.
    message: 'Operation tag "{{value}}" is not one of the sanctioned tags.'
    severity: warn
    given: $.paths.*.*.tags[*]
    then:
      function: enumeration
      functionOptions:
        values:
          - Search
          - Downloads
          - Lookup Pages

  # Parameters
  postalcodes-info-country-code-pattern:
    description: ISO 3166-1 alpha-2 country code parameters must use a 2-letter pattern.
    message: 'country parameter must be constrained to a 2-letter ISO 3166-1 alpha-2 code.'
    severity: warn
    given: $.paths.*.*.parameters[?(@.name=="country" && @.in=="query")].schema
    then:
      field: pattern
      function: pattern
      functionOptions:
        match: '\\^\\[A-Za-z\\]\\{2\\}\\$'

  postalcodes-info-postal-code-is-string:
    description: Postal codes must be modeled as strings to preserve leading zeros, spaces and punctuation.
    message: '"postal_code" must be modeled as a string, not a number.'
    severity: error
    given: $.components.schemas.PostalRecord.properties.postal_code
    then:
      field: type
      function: pattern
      functionOptions:
        match: '^string$'

  # Downloads workflow
  postalcodes-info-download-token-headers:
    description: The download-token endpoint must require X-Requested-With and Referer headers.
    message: 'createDownloadToken must enforce X-Requested-With and Referer same-origin headers.'
    severity: warn
    given: $.paths['/download-token.php'].get.parameters
    then:
      function: schema
      functionOptions:
        schema:
          type: array
          contains:
            type: object
            properties:
              name:
                enum:
                  - X-Requested-With
                  - Referer

  postalcodes-info-download-format-enum:
    description: The download endpoint must constrain format to csv, xlsx, json.
    message: 'downloadCountryDataset format parameter must be enumerated as csv | xlsx | json.'
    severity: error
    given: $.paths['/download.php'].get.parameters[?(@.name=="format")].schema
    then:
      field: enum
      function: schema
      functionOptions:
        schema:
          type: array
          items:
            type: string
          contains:
            enum:
              - csv
              - xlsx
              - json

  # Examples discipline
  postalcodes-info-200-has-example:
    description: 200 responses should include at least one example to document the JSON shape.
    message: '200 response on {{path}} should include an example.'
    severity: info
    given: $.paths.*.*.responses['200'].content.application/json
    then:
      function: truthy
      field: examples