AsyncAPI · Schema

AsyncAPI Server

An AsyncAPI Server — describes a broker or endpoint the application connects to. The protocol field selects the binding namespace (kafka, mqtt, amqp, ws, nats, etc.).

AsyncAPIEvent-Driven ArchitectureAsynchronous APIsMessage BrokersAPI SpecificationsKafkaMQTTAMQPWebSocketLinux Foundation

Properties

Name	Type	Description
host	string	Hostname (and optional port) of the server. Variables allowed via `{var}` template syntax.
pathname	string	Optional path component for protocols that need it (e.g. AMQP vhost, WebSocket path).
protocol	string	The protocol used. Drives which bindings are valid.
protocolVersion	string	Version of the protocol, e.g. `0.9.1` for AMQP, `5.0` for MQTT, `3.6.0` for Kafka.
title	string
summary	string
description	string
variables	object	Map of variables used in the host/pathname template.
security	array	Security requirements that apply to all operations on this server.
tags	array
externalDocs	object
bindings	object	Protocol-specific server bindings (e.g. kafka.schemaRegistryUrl).

View JSON Schema on GitHub

JSON Schema

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://raw.githubusercontent.com/api-evangelist/async-apis/refs/heads/main/json-schema/asyncapi-server-schema.json",
  "title": "AsyncAPI Server",
  "description": "An AsyncAPI Server — describes a broker or endpoint the application connects to. The protocol field selects the binding namespace (kafka, mqtt, amqp, ws, nats, etc.).",
  "type": "object",
  "required": ["host", "protocol"],
  "properties": {
    "host": {
      "type": "string",
      "description": "Hostname (and optional port) of the server. Variables allowed via `{var}` template syntax.",
      "examples": ["kafka.example.com:9092", "broker.hivemq.com:1883", "{env}.events.example.com"]
    },
    "pathname": {
      "type": "string",
      "description": "Optional path component for protocols that need it (e.g. AMQP vhost, WebSocket path)."
    },
    "protocol": {
      "type": "string",
      "description": "The protocol used. Drives which bindings are valid.",
      "enum": [
        "amqp", "amqps", "http", "https", "ibmmq", "jms",
        "kafka", "kafka-secure", "anypointmq", "mqtt", "secure-mqtt",
        "solace", "stomp", "stomps", "ws", "wss",
        "mercure", "googlepubsub", "pulsar", "nats", "sns", "sqs", "ros2"
      ]
    },
    "protocolVersion": {
      "type": "string",
      "description": "Version of the protocol, e.g. `0.9.1` for AMQP, `5.0` for MQTT, `3.6.0` for Kafka."
    },
    "title": {"type": "string"},
    "summary": {"type": "string"},
    "description": {"type": "string"},
    "variables": {
      "type": "object",
      "description": "Map of variables used in the host/pathname template.",
      "additionalProperties": {
        "type": "object",
        "properties": {
          "enum": {"type": "array"},
          "default": {"type": "string"},
          "description": {"type": "string"},
          "examples": {"type": "array"}
        }
      }
    },
    "security": {
      "type": "array",
      "description": "Security requirements that apply to all operations on this server.",
      "items": {"type": "object"}
    },
    "tags": {"type": "array"},
    "externalDocs": {"type": "object"},
    "bindings": {
      "type": "object",
      "description": "Protocol-specific server bindings (e.g. kafka.schemaRegistryUrl).",
      "properties": {
        "kafka": {"type": "object"},
        "mqtt": {"type": "object"},
        "amqp": {"type": "object"},
        "ws": {"type": "object"},
        "ibmmq": {"type": "object"}
      }
    }
  }
}