I can't send firebase cloud messages

[beynelmilel]

I want to send cloud message with Esp8266. I want to send to all devices without adding device token. I just added the FCM server key to the arduino code. But it didn't work.

#define API_KEY "These parts are actually full."
#define DATABASE_URL "These parts are actually full."
#define WIFI_SSID "Adus"
#define WIFI_PASSWORD "Adus.25"
#define FCM_SERVER_KEY "These parts are actually full."

#include <ESP8266WiFi.h>
#include <FirebaseESP8266.h>
#include "addons/TokenHelper.h"
#include "addons/RTDBHelper.h"

FirebaseData fbdo;
FirebaseAuth auth;
FirebaseConfig config;

void setup() {
Serial.begin(9600);
Serial.print("Nodemcu Connected");
WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
Serial.print("connecting");
while (WiFi.status() != WL_CONNECTED) {
Serial.print(".");
delay(750);
}
config.api_key = API_KEY;
auth.user.email = USER_EMAIL;
auth.user.password = USER_PASSWORD;
config.database_url = DATABASE_URL;
config.token_status_callback = tokenStatusCallback;
Firebase.begin(&config, &auth);
Firebase.setDoubleDigits(5);
delay(2000);
fbdo.fcm.setPriority("high");
fbdo.fcm.setTimeToLive(1000);
fbdo.fcm.setTopic("notification");
fbdo.fcm.begin(FCM_SERVER_KEY);
sendMessage();
}

void loop() {
}

void sendMessage()
{

fbdo.fcm.setNotifyMessage("Notification", "Hello World! ");
Serial.println("send working");
Firebase.broadcastMessage(fbdo);
Firebase.sendTopic(fbdo);
Serial.printf("Send message... %s\n", Firebase.sendMessage(fbdo, 0) ? "ok" : fbdo.errorReason().c_str());

if (fbdo.httpCode() == FIREBASE_ERROR_HTTP_CODE_OK)
    Serial.println(fbdo.fcm.getSendResult()); 
    
Serial.println();
Serial.println("send end :( ");

}

it keeps giving Send message... unknown error. All I want is to send messages like in the cloud message interface. automatically to all devices. Without using the device token.

[mobizt]

When you set the topic using fbdo.fcm.setTopic, it works only for Firebase.sendTopic.

Both Firebase.sendMessage and Firebase.broadcastMessage required device token to send message to, calling fbdo.fcm.addDeviceToken to add device token.

Without device token adding, Firebase.sendMessage will give "unknown error" and Firebase.broadcastMessage will give "bad request".

[beynelmilel]

So how can I send a notification to all devices without giving any tokens?

Send Cloud message on Firebase as in the part.
Can you give a simple code example? Just as the sendMessage() function.
I tried but failed, I would be very grateful if you could help me.

[mobizt]

Send to topic. The devices that subscribed to that topic will get notification.

[beynelmilel]

void sendMessage()
{

fbdo.fcm.setNotifyMessage("Notification", "Hello World! ");
Serial.println("send working");
Firebase.sendTopic(fbdo);
Serial.printf("Send message... %s\n", Firebase.sendTopic(fbdo, 0) ? "ok" : fbdo.errorReason().c_str());

if (fbdo.httpCode() == FIREBASE_ERROR_HTTP_CODE_OK)
    Serial.println(fbdo.fcm.getSendResult());
    
Serial.println();
Serial.println("send end :( ");

}

Is this true?

[mobizt]

The example covers all legacy API functions.

Library allows ESP device to act as server admin instead of mobile or web client.

ESP device will send message to Google server, and the server will push this message to client device later.

I'm not sure where you take FCM server key from.

The FCM server key used in this library must be taken from Firebase console -> Project settings -> Cloud Messaging.

[beynelmilel]

I get the FCM server key from Firebase console -> Project settings -> Cloud Messaging.

[mobizt]

I don't know why you call sendTopic twice

Firebase.sendTopic(fbdo); <---- ??
Serial.printf("Send message... %s\n", Firebase.sendTopic(fbdo, 0) ? "ok" : fbdo.errorReason().c_str()); <-----??

[beynelmilel]

It's my first time dealing with firebase and esp8266. I don't have much experience. I may have made a mistake.

[mobizt]

As you will see from example, function sendTopic accepts one argument (fbdo) then it should be

Serial.printf("Send message... %s\n", Firebase.sendTopic(fbdo) ? "ok" : fbdo.errorReason().c_str()); 

Or for better reading

if (Firebase.sendTopic(fbdo))
{
  Serial.println("Send message... ok");
}
else
{
  Serial.print("Send message... ");
  Serial.println(fbdo.errorReason());
}

This is where to find FCM Server key

You heed to create mobile app or web app that installed the Firebase SDK and registered to your project to get notification message.

If you still can't send the message, you should try to create new project and try again.

[beynelmilel]

Will the messages we send not appear here?

[mobizt]

You have to create real app.

That console is not the place to check the notification message as it's not the real client (no device get notified).

You should have experience to create Firebase Cloud Messaging app using Firebase SDK on supported platforms (mobile or web) that is able to send the notification message to each other to see how it works.

You can get the device registration (id) token when your app authenticated to the server.

You can use that device token with this library to send message to.

[mobizt]

As already stated in example comment, where to get start the FCM app.

Firebase-ESP8266/examples/Messaging/Messaging.ino

Lines 25 to 28 in cf26633

	// For FCM client app quick start
	// https://github.com/firebase/quickstart-android/tree/master/messaging
	// https://github.com/firebase/quickstart-ios
	// https://github.com/firebase/quickstart-js

The FCM required real device with registered app.

[mobizt]

You can create simple web app (javascript) to run on your PC web browser and test it how it works.

[beynelmilel]

Thank you, I will try and let you know.