# Novu Spectral Ruleset
# Opinionated rules enforcing the patterns observed in the Novu OpenAPI specification.
# Covers: REST surface conventions, naming, security (secretKey ApiKey header), rate-limit headers,
# pagination, response shapes, and operation metadata.

extends:
  - spectral:oas

functions: []

rules:

  # ── INFO / METADATA ─────────────────────────────────────────────────────
  info-title-novu-prefix:
    description: API title should identify the API as a Novu surface.
    message: "info.title should start with 'Novu' (got: '{{value}}')."
    severity: warn
    given: $.info.title
    then:
      function: pattern
      functionOptions:
        match: "^Novu"

  info-description-required:
    description: info.description must be present and non-empty.
    severity: warn
    given: $.info
    then:
      field: description
      function: truthy

  info-contact-required:
    description: info.contact should be defined.
    severity: info
    given: $.info
    then:
      field: contact
      function: truthy

  info-license-required:
    description: info.license should be defined (Novu is MIT licensed).
    severity: info
    given: $.info
    then:
      field: license
      function: truthy

  info-version-semver:
    description: info.version should follow semantic versioning.
    severity: warn
    given: $.info.version
    then:
      function: pattern
      functionOptions:
        match: "^\\d+\\.\\d+\\.\\d+(-[A-Za-z0-9.-]+)?$"

  # ── OPENAPI VERSION ─────────────────────────────────────────────────────
  openapi-version-3:
    description: Use OpenAPI 3.x.
    severity: error
    given: $.openapi
    then:
      function: pattern
      functionOptions:
        match: "^3\\."

  # ── SERVERS ─────────────────────────────────────────────────────────────
  servers-https-only:
    description: All servers MUST use HTTPS.
    severity: error
    given: $.servers[*].url
    then:
      function: pattern
      functionOptions:
        match: "^https://"

  servers-novu-domain:
    description: Server URLs should target a novu.co domain.
    severity: info
    given: $.servers[*].url
    then:
      function: pattern
      functionOptions:
        match: "novu\\.co"

  # ── PATHS — NAMING ──────────────────────────────────────────────────────
  paths-kebab-case:
    description: Path segments (excluding parameters) should use kebab-case.
    severity: warn
    given: $.paths.*~
    then:
      function: pattern
      functionOptions:
        match: "^(/(v[0-9]+|[a-z0-9][a-z0-9-]*|\\{[^/]+\\}))+$"

  paths-version-prefix:
    description: Every path should be versioned (e.g. /v1/, /v2/).
    severity: warn
    given: $.paths.*~
    then:
      function: pattern
      functionOptions:
        match: "^/v[0-9]+/"

  paths-no-trailing-slash:
    description: Paths must not end with a trailing slash.
    severity: error
    given: $.paths.*~
    then:
      function: pattern
      functionOptions:
        notMatch: ".+/$"

  paths-no-query-string:
    description: Path keys must not include query strings.
    severity: error
    given: $.paths.*~
    then:
      function: pattern
      functionOptions:
        notMatch: "\\?"

  # ── OPERATIONS ──────────────────────────────────────────────────────────
  operation-operationid-required:
    description: Every operation must declare an operationId.
    severity: error
    given: $.paths.*[get,post,put,patch,delete]
    then:
      field: operationId
      function: truthy

  operation-operationid-camelcase:
    description: operationId should be camelCase (Novu uses ControllerName_methodName pattern).
    severity: warn
    given: $.paths.*[get,post,put,patch,delete].operationId
    then:
      function: pattern
      functionOptions:
        match: "^[A-Za-z][A-Za-z0-9_]*$"

  operation-summary-required:
    description: Every operation must declare a summary.
    severity: error
    given: $.paths.*[get,post,put,patch,delete]
    then:
      field: summary
      function: truthy

  operation-summary-novu-prefix:
    description: Operation summary should start with the 'Novu' provider prefix and be in Title Case.
    severity: warn
    given: $.paths.*[get,post,put,patch,delete].summary
    then:
      function: pattern
      functionOptions:
        match: "^Novu "

  operation-description-required:
    description: Every operation should declare a description.
    severity: warn
    given: $.paths.*[get,post,put,patch,delete]
    then:
      field: description
      function: truthy

  operation-tags-required:
    description: Every operation should declare at least one tag.
    severity: warn
    given: $.paths.*[get,post,put,patch,delete]
    then:
      field: tags
      function: truthy

  # ── TAGS ────────────────────────────────────────────────────────────────
  tags-title-case:
    description: Tag names should be in Title Case (matches the resource grouping in the Novu Dashboard).
    severity: warn
    given: $.tags[*].name
    then:
      function: pattern
      functionOptions:
        match: "^[A-Z][A-Za-z0-9]*( [A-Z][A-Za-z0-9]*)*$"

  # ── PARAMETERS ──────────────────────────────────────────────────────────
  parameter-description-required:
    description: Every parameter should declare a description.
    severity: warn
    given: $.paths.*[get,post,put,patch,delete].parameters[*]
    then:
      field: description
      function: truthy

  parameter-camelcase:
    description: Parameter names should be camelCase (Novu convention, e.g. subscriberId, environmentId).
    severity: warn
    given: $.paths.*[get,post,put,patch,delete].parameters[?(@.in!='header')].name
    then:
      function: pattern
      functionOptions:
        match: "^[a-z][A-Za-z0-9]*$"

  parameter-pagination-cursor-limit:
    description: Paginated list endpoints should expose cursor + limit parameters.
    severity: info
    given: $.paths.*.get.parameters[?(@.name=='limit')]
    then:
      field: schema
      function: truthy

  # ── REQUEST BODIES ──────────────────────────────────────────────────────
  request-body-application-json:
    description: Request bodies should accept application/json.
    severity: warn
    given: $.paths.*[post,put,patch].requestBody.content
    then:
      field: "application/json"
      function: truthy

  # ── RESPONSES ───────────────────────────────────────────────────────────
  response-2xx-required:
    description: Every operation must define at least one 2xx response.
    severity: error
    given: $.paths.*[get,post,put,patch,delete].responses
    then:
      function: schema
      functionOptions:
        schema:
          anyOf:
            - required: ["200"]
            - required: ["201"]
            - required: ["202"]
            - required: ["204"]

  response-401-required:
    description: Authenticated operations should document the 401 Unauthorized response.
    severity: warn
    given: $.paths.*[get,post,put,patch,delete].responses
    then:
      field: "401"
      function: truthy

  response-429-required:
    description: Rate-limited operations should document the 429 Too Many Requests response.
    severity: info
    given: $.paths.*[get,post,put,patch,delete].responses
    then:
      field: "429"
      function: truthy

  response-error-content-type:
    description: Error responses should return application/json.
    severity: warn
    given: $.paths.*[get,post,put,patch,delete].responses[?(@property.match(/^[45]/))].content
    then:
      field: "application/json"
      function: truthy

  response-rate-limit-headers:
    description: Successful responses should expose RateLimit-Limit / RateLimit-Remaining / RateLimit-Reset / RateLimit-Policy headers per Novu's policy.
    severity: info
    given: $.paths.*[get,post,put,patch,delete].responses[?(@property.match(/^2/))].headers
    then:
      field: "RateLimit-Limit"
      function: truthy

  response-idempotency-headers:
    description: Mutating operations should expose Idempotency-Key / Idempotency-Replay response headers.
    severity: info
    given: $.paths.*[post,put,patch,delete].responses[?(@property.match(/^2/))].headers
    then:
      field: "Idempotency-Key"
      function: truthy

  # ── SCHEMAS ─────────────────────────────────────────────────────────────
  schema-property-camelcase:
    description: Schema property names should be camelCase (Novu DTO convention).
    severity: warn
    given: $.components.schemas[*].properties.*~
    then:
      function: pattern
      functionOptions:
        match: "^[a-z][A-Za-z0-9]*$"

  schema-type-required:
    description: Top-level schemas must declare a type.
    severity: warn
    given: $.components.schemas[*]
    then:
      function: schema
      functionOptions:
        schema:
          anyOf:
            - required: ["type"]
            - required: ["$ref"]
            - required: ["oneOf"]
            - required: ["anyOf"]
            - required: ["allOf"]

  schema-dto-suffix:
    description: Request/response DTO schemas should use the Dto suffix Novu adopts (RequestDto / ResponseDto / Dto).
    severity: info
    given: $.components.schemas
    then:
      function: schema
      functionOptions:
        schema:
          patternProperties:
            "Dto$": {}

  # ── SECURITY ────────────────────────────────────────────────────────────
  security-scheme-secretkey-required:
    description: components.securitySchemes must define the secretKey ApiKey scheme used by Novu.
    severity: error
    given: $.components.securitySchemes
    then:
      field: secretKey
      function: truthy

  security-apikey-header:
    description: The secretKey scheme should be an ApiKey scheme delivered in the Authorization header.
    severity: warn
    given: $.components.securitySchemes.secretKey
    then:
      function: schema
      functionOptions:
        schema:
          type: object
          properties:
            type: { const: apiKey }
            in: { const: header }
            name: { const: Authorization }

  # ── HTTP METHOD CONVENTIONS ─────────────────────────────────────────────
  get-no-request-body:
    description: GET operations should not declare a request body.
    severity: error
    given: $.paths.*.get.requestBody
    then:
      function: falsy

  delete-204-or-200:
    description: DELETE operations should respond with 200 or 204.
    severity: info
    given: $.paths.*.delete.responses
    then:
      function: schema
      functionOptions:
        schema:
          anyOf:
            - required: ["200"]
            - required: ["202"]
            - required: ["204"]

  # ── GENERAL QUALITY ─────────────────────────────────────────────────────
  components-schemas-defined:
    description: components.schemas should be defined.
    severity: warn
    given: $.components
    then:
      field: schemas
      function: truthy

  no-empty-description:
    description: Descriptions, when present, must be non-empty.
    severity: warn
    given: $..description
    then:
      function: truthy