{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://raw.githubusercontent.com/api-evangelist/sunset-header/main/json-schema/sunset-header-schema.json",
  "title": "Sunset Header",
  "description": "Schema for representing API deprecation lifecycle data using the Sunset HTTP header field (RFC 8594) and Deprecation HTTP header field (RFC 9745).",
  "type": "object",
  "properties": {
    "endpoint": {
      "type": "string",
      "format": "uri",
      "description": "The URI of the API endpoint subject to deprecation."
    },
    "sunsetDate": {
      "type": "string",
      "format": "date-time",
      "description": "The date and time when the endpoint will become unresponsive. Corresponds to the value of the Sunset HTTP header (RFC 8594) in ISO 8601 format."
    },
    "deprecationDate": {
      "type": "string",
      "format": "date-time",
      "description": "The date and time when the endpoint was or will be deprecated. Corresponds to the Deprecation HTTP header (RFC 9745). Must not be later than sunsetDate if both are present."
    },
    "sunsetHeaderValue": {
      "type": "string",
      "description": "The raw HTTP-date value of the Sunset header as sent in the response (e.g., 'Sat, 31 Dec 2026 23:59:59 GMT').",
      "example": "Sat, 31 Dec 2026 23:59:59 GMT"
    },
    "deprecationHeaderValue": {
      "type": "string",
      "description": "The raw structured-date value of the Deprecation header as sent in the response (e.g., '@1688169599').",
      "example": "@1688169599"
    },
    "migrationUrl": {
      "type": "string",
      "format": "uri",
      "description": "URL of the migration guide or replacement resource. Communicated via the Link header with rel='sunset' or rel='deprecation'."
    },
    "replacementEndpoint": {
      "type": "string",
      "format": "uri",
      "description": "The URI of the replacement endpoint that consumers should migrate to."
    },
    "status": {
      "type": "string",
      "enum": ["active", "deprecated", "sunset"],
      "description": "Current lifecycle status of the endpoint. 'active' is fully operational; 'deprecated' is operational but scheduled for retirement; 'sunset' is end-of-life."
    },
    "linkHeaders": {
      "type": "array",
      "description": "Array of Link header values associated with this endpoint's deprecation.",
      "items": {
        "type": "object",
        "properties": {
          "url": {
            "type": "string",
            "format": "uri",
            "description": "Target URL of the link."
          },
          "rel": {
            "type": "string",
            "enum": ["sunset", "deprecation", "successor-version", "latest-version"],
            "description": "Link relation type."
          }
        },
        "required": ["url", "rel"]
      }
    }
  },
  "required": ["endpoint", "status"],
  "examples": [
    {
      "endpoint": "https://api.example.com/v1/users",
      "status": "deprecated",
      "deprecationDate": "2026-01-01T00:00:00Z",
      "deprecationHeaderValue": "@1735689600",
      "sunsetDate": "2027-01-01T00:00:00Z",
      "sunsetHeaderValue": "Fri, 01 Jan 2027 00:00:00 GMT",
      "migrationUrl": "https://developer.example.com/migration-v2",
      "replacementEndpoint": "https://api.example.com/v2/users",
      "linkHeaders": [
        {
          "url": "https://developer.example.com/migration-v2",
          "rel": "deprecation"
        },
        {
          "url": "https://api.example.com/v2/users",
          "rel": "successor-version"
        }
      ]
    }
  ]
}