Ariba Guided Buying API Rules

# ariba-guided-buying — Spectral ruleset (strengthened)
# Plain Spectral. Existing hand-authored rules preserved; measured rules added
# from this provider's own OpenAPI conventions by strengthen_ruleset.py,
# then self-validated against the spec.
#
# Provenance:
#   - servers-https-only: 100% of servers already https (error)
#   - servers-expected-domain: 4/4 servers on ariba.com
#   - path-params-casing: camel @ 100% (n=3)
#   - operationid-casing: camel @ 100% (n=6)
#   - schema-names-casing: pascal @ 100% (n=15)
#   - schema-properties-casing: snake @ 62% (n=42)
#   - security: global (root) — NOT emitting operation-security-required
#   - error-schema-defined: ErrorResponse
#   - operation-documents-400: 100% adherence
#   - operation-documents-500: 100% adherence
#   - merge: kept 34 existing, added 5 measured, upgraded 0
#   - added: path-params-casing, schema-names-casing, schema-properties-casing, error-schema-defined, no-empty-descriptions
extends:
  - spectral:oas
rules:
  info-title-required:
    description: API title must be defined and follow the "Ariba Guided Buying - {API Name}" pattern.
    severity: error
    given: $.info
    then:
      field: title
      function: truthy
  info-title-prefix:
    description: API title should start with "Ariba Guided Buying".
    severity: warn
    given: $.info.title
    then:
      function: pattern
      functionOptions:
        match: ^Ariba Guided Buying
  info-description-required:
    description: API info must have a description.
    severity: error
    given: $.info
    then:
      field: description
      function: truthy
  info-version-required:
    description: API version must be defined.
    severity: error
    given: $.info
    then:
      field: version
      function: truthy
  info-contact-required:
    description: API info should include contact information.
    severity: warn
    given: $.info
    then:
      field: contact
      function: truthy
  openapi-version-3:
    description: APIs must use OpenAPI 3.0.x.
    severity: error
    given: $
    then:
      field: openapi
      function: pattern
      functionOptions:
        match: ^3\.0\.
  servers-required:
    description: Servers must be defined.
    severity: error
    given: $
    then:
      field: servers
      function: truthy
  servers-https-only:
    description: All server URLs must use HTTPS.
    severity: error
    given: $.servers[*].url
    then:
      function: pattern
      functionOptions:
        match: ^https://
  servers-openapi-ariba-host:
    description: Production server should use openapi.ariba.com host.
    severity: warn
    given: $.servers[*].url
    then:
      function: pattern
      functionOptions:
        match: openapi\.ariba\.com
  paths-kebab-case:
    description: Path segments must use kebab-case.
    severity: warn
    given: $.paths[*]~
    then:
      function: pattern
      functionOptions:
        match: ^(\/[a-zA-Z0-9{}\$._-]+)+$
  paths-no-trailing-slash:
    description: Paths must not have a trailing slash.
    severity: warn
    given: $.paths[*]~
    then:
      function: pattern
      functionOptions:
        notMatch: \/$
  operation-summary-required:
    description: Every operation must have a summary.
    severity: error
    given: $.paths[*][get,post,put,patch,delete]
    then:
      field: summary
      function: truthy
  operation-summary-prefix:
    description: Operation summaries should start with "Ariba Guided Buying".
    severity: warn
    given: $.paths[*][get,post,put,patch,delete].summary
    then:
      function: pattern
      functionOptions:
        match: ^Ariba Guided Buying
  operation-description-required:
    description: Every operation must have a description.
    severity: error
    given: $.paths[*][get,post,put,patch,delete]
    then:
      field: description
      function: truthy
  operation-id-required:
    description: Every operation must have an operationId.
    severity: error
    given: $.paths[*][get,post,put,patch,delete]
    then:
      field: operationId
      function: truthy
  operation-id-camel-case:
    description: operationId should use camelCase.
    severity: warn
    given: $.paths[*][get,post,put,patch,delete].operationId
    then:
      function: pattern
      functionOptions:
        match: ^[a-z][a-zA-Z0-9]*$
  operation-tags-required:
    description: Every operation must have at least one tag.
    severity: error
    given: $.paths[*][get,post,put,patch,delete]
    then:
      field: tags
      function: truthy
  parameter-description-required:
    description: All parameters must have a description.
    severity: error
    given: $.paths[*][get,post,put,patch,delete].parameters[*]
    then:
      field: description
      function: truthy
  parameter-schema-required:
    description: All parameters must have a schema.
    severity: error
    given: $.paths[*][get,post,put,patch,delete].parameters[*]
    then:
      field: schema
      function: truthy
  parameter-realm-naming:
    description: Realm parameter should be named "realm" (SAP Ariba convention).
    severity: info
    given: $.paths[*][get,post,put,patch,delete].parameters[*]
    then:
      function: pattern
      functionOptions:
        match: ^(realm|\$filter|\$count|\$skip|\$select|\$expand|\$search|shopID|entity_id|entity_type)$
  request-body-description-required:
    description: Request bodies should have a description.
    severity: warn
    given: $.paths[*][post,put,patch].requestBody
    then:
      field: description
      function: truthy
  request-body-json-content:
    description: Request bodies should define application/json content.
    severity: warn
    given: $.paths[*][post,put,patch].requestBody.content
    then:
      field: application/json
      function: truthy
  response-success-required:
    description: Every operation must have a 200 or 201 success response.
    severity: error
    given: $.paths[*][get,post,put,patch,delete].responses
    then:
      function: schema
      functionOptions:
        schema:
          anyOf:
          - required:
            - '200'
          - required:
            - '201'
          - required:
            - '204'
  response-400-recommended:
    description: Operations should define a 400 Bad Request response.
    severity: warn
    given: $.paths[*][get,post,put,patch,delete].responses
    then:
      field: '400'
      function: truthy
  response-401-recommended:
    description: Operations should define a 401 Unauthorized response.
    severity: warn
    given: $.paths[*][get,post,put,patch,delete].responses
    then:
      field: '401'
      function: truthy
  response-500-recommended:
    description: Operations should define a 500 Internal Server Error response.
    severity: warn
    given: $.paths[*][get,post,put,patch,delete].responses
    then:
      field: '500'
      function: truthy
  response-description-required:
    description: All responses must have a description.
    severity: error
    given: $.paths[*][get,post,put,patch,delete].responses[*]
    then:
      field: description
      function: truthy
  schema-property-description-recommended:
    description: Schema properties should have descriptions.
    severity: info
    given: $.components.schemas[*].properties[*]
    then:
      field: description
      function: truthy
  schema-type-defined:
    description: Component schemas should define a type.
    severity: warn
    given: $.components.schemas[*]
    then:
      field: type
      function: truthy
  security-schemes-defined:
    description: Security schemes must be defined in components.
    severity: error
    given: $.components.securitySchemes
    then:
      function: truthy
  security-oauth2-ariba:
    description: SAP Ariba APIs should use OAuth 2.0 with api.ariba.com token URL.
    severity: warn
    given: $.components.securitySchemes.OAuth2.flows.clientCredentials.tokenUrl
    then:
      function: pattern
      functionOptions:
        match: api\.ariba\.com
  get-no-request-body:
    description: GET operations must not have a request body.
    severity: error
    given: $.paths[*].get
    then:
      field: requestBody
      function: falsy
  delete-no-request-body:
    description: DELETE operations should not have a request body.
    severity: warn
    given: $.paths[*].delete
    then:
      field: requestBody
      function: falsy
  microcks-operation-extension:
    description: Operations should include x-microcks-operation for mock server configuration.
    severity: info
    given: $.paths[*][get,post,put,patch,delete]
    then:
      field: x-microcks-operation
      function: truthy
  path-params-casing:
    description: Path parameters should be camelCase (the dominant convention in this API).
    severity: warn
    given: $.paths[*].parameters[?(@.in=='path')].name
    then:
      function: pattern
      functionOptions:
        match: ^[a-z][A-Za-z0-9]*$
  schema-names-casing:
    description: Component schema names should be PascalCase (the dominant convention in this API).
    severity: warn
    given: $.components.schemas
    then:
      field: '@key'
      function: casing
      functionOptions:
        type: pascal
  schema-properties-casing:
    description: Schema properties should be snake_case (the dominant convention in this API).
    severity: info
    given: $.components.schemas[*].properties
    then:
      field: '@key'
      function: casing
      functionOptions:
        type: snake
  error-schema-defined:
    description: A shared error schema (ErrorResponse) should be defined for error payloads.
    severity: warn
    given: $.components.schemas
    then:
      field: ErrorResponse
      function: truthy
  no-empty-descriptions:
    description: Descriptions must not be empty strings.
    severity: warn
    given: $..description
    then:
      function: truthy