NATS Connections API

openapi: 3.1.0
info:
  title: NATS Monitoring HTTP Accounts Connections API
  description: The NATS server exposes a monitoring HTTP endpoint that provides real-time server statistics including connection info, route details, subscription data, JetStream metrics, and health checks for observability and operations.
  version: 2.10.0
  contact:
    name: NATS.io
    url: https://nats.io/
  license:
    name: Apache 2.0
    url: https://www.apache.org/licenses/LICENSE-2.0
servers:
- url: http://localhost:8222
  description: Default NATS monitoring endpoint
tags:
- name: Connections
paths:
  /connz:
    get:
      summary: Connection information
      operationId: getConnz
      tags:
      - Connections
      description: Reports detailed information on current and recently closed connections.
      parameters:
      - name: sort
        in: query
        schema:
          type: string
          enum:
          - cid
          - start
          - subs
          - pending
          - msgs_to
          - msgs_from
          - bytes_to
          - bytes_from
          - last
          - idle
          - uptime
          - stop
          - reason
      - name: auth
        in: query
        schema:
          type: boolean
      - name: subs
        in: query
        schema:
          type: boolean
      - name: offset
        in: query
        schema:
          type: integer
      - name: limit
        in: query
        schema:
          type: integer
      - name: cid
        in: query
        schema:
          type: integer
      - name: state
        in: query
        schema:
          type: string
          enum:
          - open
          - closed
          - any
      responses:
        '200':
          description: Connection details
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Connz'
components:
  schemas:
    Connz:
      type: object
      properties:
        now:
          type: string
        num_connections:
          type: integer
        total:
          type: integer
        offset:
          type: integer
        limit:
          type: integer
        connections:
          type: array
          items:
            type: object
            properties:
              cid:
                type: integer
              kind:
                type: string
              type:
                type: string
              ip:
                type: string
              port:
                type: integer
              start:
                type: string
              last_activity:
                type: string
              rtt:
                type: string
              uptime:
                type: string
              idle:
                type: string
              pending_bytes:
                type: integer
              in_msgs:
                type: integer
              out_msgs:
                type: integer
              in_bytes:
                type: integer
              out_bytes:
                type: integer
              subscriptions:
                type: integer
              name:
                type: string
              lang:
                type: string
              version:
                type: string
              account:
                type: string