Firebase Cloud Messaging (HTTP v1)

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Overview

A client-mode connector for a curated messaging slice of the Firebase Cloud Messaging HTTP v1 API:

Catalog connector event	Entity / path	Notes
POST messages:send (token/topic)	`POST /v1/projects/{project_id}/messages:send`	Notification to registration token or topic
POST data message (app sync)	`POST /v1/projects/{project_id}/messages:send`	Data-only `message.data` (same endpoint)

Default BASE_ADDRESS is https://fcm.googleapis.com. Topics use messaging/fcm/<object>/<verb>.

Auth is OAuth 2.0 Bearer from a Google service account with scope https://www.googleapis.com/auth/firebase.messaging. Prefer Hub secrets FCM_ACCESS_TOKEN and project id FCM_PROJECT_ID (alias FIREBASE_PROJECT_ID). Status remains blocked until an authenticated live smoke succeeds.

Basic Syntax

# Coreflux REST_API template — Firebase Cloud Messaging HTTP v1
# Auth: Authorization: Bearer {value.json.access_token}
# BASE_ADDRESS: https://fcm.googleapis.com

DEFINE ROUTE FirebaseCloudMessagingRestApi WITH TYPE REST_API
    ADD REST_API_CONFIG
        WITH BASE_ADDRESS "https://fcm.googleapis.com"
        WITH ENABLE_CLIENT "true"
        WITH USE_SSL "true"
        WITH REQUEST_TIMEOUT '60'
        WITH DEFAULT_CONTENT_TYPE "application/json"
    ADD EVENT Sendmessage
        WITH SOURCE_TOPIC "messaging/fcm/message/send"
        WITH DESTINATION_TOPIC "messaging/fcm/message/send/response"
        WITH METHOD "POST"
        WITH ENDPOINT "/v1/projects/{value.json.project_id}/messages:send"
        WITH HEADERS
            ADD "Accept" "application/json"
            ADD "Content-Type" "application/json"
            ADD "Authorization" "Bearer {value.json.access_token}"
        WITH BODY "{payload}"
    ADD EVENT Senddatamessage
        WITH SOURCE_TOPIC "messaging/fcm/message/send-data"
        WITH DESTINATION_TOPIC "messaging/fcm/message/send-data/response"
        WITH METHOD "POST"
        WITH ENDPOINT "/v1/projects/{value.json.project_id}/messages:send"
        WITH HEADERS
            ADD "Accept" "application/json"
            ADD "Content-Type" "application/json"
            ADD "Authorization" "Bearer {value.json.access_token}"
        WITH BODY "{payload}"

Events

Event	Method	Endpoint	Request topic	Response topic
Sendmessage	POST	`/v1/projects/{project_id}/messages:send`	`messaging/fcm/message/send`	`messaging/fcm/message/send/response`
Senddatamessage	POST	`/v1/projects/{project_id}/messages:send`	`messaging/fcm/message/send-data`	`messaging/fcm/message/send-data/response`

Auth

Create a Firebase / Google Cloud service account with permission to use FCM (scope https://www.googleapis.com/auth/firebase.messaging).
Exchange a signed JWT for a short-lived access token at https://oauth2.googleapis.com/token (or use Application Default Credentials / gcloud offline). Store the token in Hub as FCM_ACCESS_TOKEN.
Set connector BASE_ADDRESS to https://fcm.googleapis.com.
Pass access_token and project_id on MQTT JSON payloads so the Authorization header and path resolve. Put the FCM message object (and optional validateOnly) in the same JSON — {payload} is the HTTP body.
Never commit service-account JSON, GOOGLE_APPLICATION_CREDENTIALS files, or live tokens.
Successful send returns HTTP 200 with a Message including name. Use validateOnly: true for dry-run smokes.

Example payloads

sendMessage (token notification):

{
  "project_id": "YOUR_FIREBASE_PROJECT_ID",
  "access_token": "YOUR_FCM_ACCESS_TOKEN",
  "message": {
    "token": "YOUR_DEVICE_REGISTRATION_TOKEN",
    "notification": {
      "title": "Coreflux alarm — Zone A",
      "body": "RMS exceeded limit on Zone A"
    }
  }
}

sendMessage (topic):

{
  "project_id": "YOUR_FIREBASE_PROJECT_ID",
  "access_token": "YOUR_FCM_ACCESS_TOKEN",
  "message": {
    "topic": "plant-alarms",
    "notification": {
      "title": "Plant-wide alert",
      "body": "Line 3 stopped"
    }
  }
}

sendDataMessage (app sync):

{
  "project_id": "YOUR_FIREBASE_PROJECT_ID",
  "access_token": "YOUR_FCM_ACCESS_TOKEN",
  "message": {
    "token": "YOUR_DEVICE_REGISTRATION_TOKEN",
    "data": {
      "device_id": "zone-a-vib-01",
      "metric": "vibration_rms",
      "value": "12.4"
    }
  }
}

validateOnly dry-run:

{
  "project_id": "YOUR_FIREBASE_PROJECT_ID",
  "access_token": "YOUR_FCM_ACCESS_TOKEN",
  "validateOnly": true,
  "message": {
    "topic": "coreflux-smoke",
    "notification": { "title": "smoke", "body": "validateOnly" }
  }
}

Install

The template ships with the broker. List it with -listTemplates or fetch it from the Hub catalog.
Deploy with -addRoute from FirebaseCloudMessagingRestApi.lot (not hub-metadata.lot).

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Product Updates

Overview

Basic Syntax

Events

Auth

Example payloads

Install

See also

​Overview

​Basic Syntax

​Events

​Auth

​Example payloads

​Install

​See also

Overview

Basic Syntax

Events

Auth

Example payloads

Install

See also