Backstage

Backstage Bus API

The Bus API from Backstage — 3 operation(s) for bus.

Documentation GitHub OpenAPI

Operations 3

POST /bus/v1/events Post event #

PUT /bus/v1/subscriptions/{subscriptionId} Put subscription #

GET /bus/v1/subscriptions/{subscriptionId}/events Get subscription events #

Work with this as data

Every API here is available over the APIs.io API and to AI agents over MCP.

MCP server

One button, every client — Claude, Cursor, VS Code and the rest.

https://apis.io/mcp

Tools for apis

7 MCP tools reach this

find_apisBrowse and filter every API in the catalog.
get_api_artifactsOne API's artifacts, grouped by type.
get_openapiThe primary OpenAPI for this API.
find_similar_apisAPIs that look like this one.
apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
resolveTurn a domain, URL or GitHub org into the provider it belongs to.
find_cohortsEvery scored population of providers in the catalog.

All 92 tools →

Call it yourself

curl for this page

This API

curl "https://apis.io/api/v1/apis/backstage:backstage-bus-api"

All apis

curl "https://apis.io/api/v1/apis?limit=25"

Calls without X-API-Key need no key. Calls with it need a paid plan — get a key.

Get an API key

Free tier, no form to fill in. Signing in shares your email address with us — we store it to create your key and to recognise you if you sign in with another provider. See our Privacy Policy and Terms.

GitHub Google LinkedIn

A second provider on the same verified email joins the account you already have.

OpenAPI Specification

openapi: 3.2.0
info:
  title: events Bus API
  version: '1'
  description: The Backstage backend plugin that powers the events system.
  license:
    name: Apache-2.0
    url: http://www.apache.org/licenses/LICENSE-2.0.html
  contact: {}
servers:
- url: /
tags:
- name: Bus
paths:
  /bus/v1/events:
    post:
      operationId: PostEvent
      description: Publish a new event
      responses:
        '201':
          description: The event was published successfully
        '204':
          description: The event did not need to be published as all subscribers have already been notified
        default:
          $ref: '#/components/responses/ErrorResponse'
      security:
      - {}
      - JWT: []
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - event
              properties:
                event:
                  $ref: '#/components/schemas/Event'
                notifiedSubscribers:
                  type: array
                  description: The IDs of subscriptions that have already received this event
                  items:
                    type: string
            examples:
              Publishing a simple Event:
                value:
                  event:
                    topic: test-topic
                    payload:
                      myData: foo
      tags:
      - Bus
      summary: Post event
      x-summary-source: derived
  /bus/v1/subscriptions/{subscriptionId}:
    put:
      operationId: PutSubscription
      description: Ensures that the subscription exists with the provided configuration
      responses:
        '201':
          description: The subscription exists or was created successfully
        default:
          $ref: '#/components/responses/ErrorResponse'
      security:
      - {}
      - JWT: []
      parameters:
      - $ref: '#/components/parameters/subscriptionId'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - topics
              properties:
                topics:
                  type: array
                  description: The topics to subscribe to
                  items:
                    type: string
            examples:
              Subscribing to a single topic:
                value:
                  topics:
                  - test-topic
      tags:
      - Bus
      summary: Put subscription
      x-summary-source: derived
  /bus/v1/subscriptions/{subscriptionId}/events:
    get:
      operationId: GetSubscriptionEvents
      description: Get new events for the provided subscription
      responses:
        '200':
          description: New events
          content:
            application/json:
              schema:
                type: object
                required:
                - events
                properties:
                  events:
                    type: array
                    items:
                      $ref: '#/components/schemas/Event'
        '202':
          description: No new events are available. Response will block until the client should try again.
        default:
          $ref: '#/components/responses/ErrorResponse'
      security:
      - {}
      - JWT: []
      parameters:
      - $ref: '#/components/parameters/subscriptionId'
      tags:
      - Bus
      summary: Get subscription events
      x-summary-source: derived
components:
  parameters:
    subscriptionId:
      name: subscriptionId
      in: path
      required: true
      schema:
        type: string
  schemas:
    Event:
      type: object
      required:
      - topic
      - payload
      properties:
        topic:
          type: string
          description: The topic that the event is published on
        payload:
          description: The event payload
    Error:
      type: object
      properties:
        error:
          type: object
          properties:
            name:
              type: string
            message:
              type: string
          required:
          - name
          - message
        request:
          type: object
          properties:
            method:
              type: string
            url:
              type: string
          required:
          - method
          - url
        response:
          type: object
          properties:
            statusCode:
              type: number
          required:
          - statusCode
      required:
      - error
      - request
      - response
  responses:
    ErrorResponse:
      description: An error response from the backend.
      content:
        application/json; charset=utf-8:
          schema:
            $ref: '#/components/schemas/Error'
  securitySchemes:
    JWT:
      type: http
      scheme: bearer
      bearerFormat: JWT