Amqp Message Properties Structure

{
  "$id": "https://raw.githubusercontent.com/api-evangelist/amqp/refs/heads/main/json-structure/amqp-message-properties-structure.json",
  "$schema": "https://json-structure.org/meta/core/v0/#",
  "name": "AMQP Message Properties",
  "description": "Schema describing the standard AMQP 0-9-1 message properties (Basic.Properties). These properties are defined in the AMQP specification and provide metadata about the message content, delivery, and routing.",
  "type": "object",
  "properties": {
    "contentType": {
      "type": "string",
      "description": "MIME content type of the message body (e.g., application/json, text/plain).",
      "examples": [
        "application/json",
        "text/plain",
        "application/octet-stream"
      ]
    },
    "contentEncoding": {
      "type": "string",
      "description": "MIME content encoding of the message body (e.g., utf-8, gzip).",
      "examples": [
        "utf-8",
        "gzip"
      ]
    },
    "headers": {
      "type": "object",
      "description": "Application-specific message headers as an AMQP field table.",
      "additionalProperties": true
    },
    "deliveryMode": {
      "type": "int32",
      "description": "Message delivery mode. 1 = non-persistent (may be lost on broker restart), 2 = persistent (written to disk).",
      "enum": [
        1,
        2
      ]
    },
    "priority": {
      "type": "int32",
      "description": "Message priority level from 0 (lowest) to 9 (highest).",
      "minimum": 0,
      "maximum": 9
    },
    "correlationId": {
      "type": "uuid",
      "description": "Application-defined correlation identifier, typically used to correlate RPC responses with requests."
    },
    "replyTo": {
      "type": "string",
      "description": "Name of the queue to which replies should be sent, used in the request/reply messaging pattern."
    },
    "expiration": {
      "type": "string",
      "description": "Message expiration (TTL) as a string representing milliseconds. The message will be discarded after this duration.",
      "pattern": "^[0-9]+$"
    },
    "messageId": {
      "type": "uuid",
      "description": "Application-defined unique message identifier."
    },
    "timestamp": {
      "type": "int32",
      "description": "Message timestamp as a UNIX epoch timestamp (seconds since 1970-01-01T00:00:00Z)."
    },
    "type": {
      "type": "string",
      "description": "Application-defined message type name, used to describe the kind of message.",
      "examples": [
        "order.created",
        "payment.processed",
        "user.registered"
      ]
    },
    "userId": {
      "type": "string",
      "description": "The user ID of the authenticated user who published the message. Validated by the broker against the connection credentials."
    },
    "appId": {
      "type": "string",
      "description": "Application identifier of the publishing application."
    },
    "clusterId": {
      "type": "string",
      "description": "Cluster identifier for use by clustering applications. Deprecated in AMQP 0-9-1."
    }
  },
  "additionalProperties": false
}