使用Firebase云消息传递发送通知

Question

我在个人项目中使用android + firebase。现在，我正在尝试在客户进行购买时向特定用户发送通知。我实现了一些关于fcm的教程，但我不知道为什么这些函数不起作用。 index.js是下一个：

// The Cloud Functions for Firebase SDK to create Cloud Functions and setup triggers.
const functions = require('firebase-functions');

// The Firebase Admin SDK to access the Firebase Realtime Database.
const admin = require('firebase-admin');
admin.initializeApp(functions.config().firebase);
var request = require('request');
var API_KEY = "AAAAV42gvFo:....."; 


// Get a database reference to our posts
var db = admin.database();
var ref = db.ref("purchases_cart");

function listenForNotificationRequests() {
// Attach an asynchronous callback to read the data at our posts reference
ref.on("child_added", function(snapshot, prevChildKey) {
  var newPost = snapshot.val();
  console.log("Uid: " + newPost.Uid);
  console.log("fcmToken: " + newPost.fcmToken);
  console.log("purchaseID: " + snapshot.key);
  sendNotificationToUser(
      newPost.fcmToken, 
      snapshot.key,
      newPost.Uid,
      function() {
        snapshot.ref.remove();
      }
    );
});
}

function sendNotificationToUser(fcmToken, message, uid, onSuccess) {
  request({
    url: 'https://fcm.googleapis.com/fcm/send',
    method: 'POST',
    headers: {
      'Content-Type' :' application/json',
      'Authorization': 'key='+API_KEY
    },
    body: JSON.stringify({
      notification: {
        "title": message,
        "body": "some text for body notification",
        "sound" : "default"
      },
      data:{
        "prov_Uid" : uid,
        "type": "new_sale",
        "sale_ID": message
      },
      "to" : fcmToken,
      "priority": "high",
      "time_to_live" : 3600
    })
  }, function(error, response, body) {
    if (error) { console.error(error); }
    else if (response.statusCode >= 400) { 
      console.error('HTTP Error: '+response.statusCode+' - '+response.statusMessage); 
    }
    else {
      onSuccess();
    }
  });
}

// start listening
listenForNotificationRequests();

在android中我的MessageReceived实现如下：

public class MyFirebaseMessagingService extends FirebaseMessagingService {
    private static final String TAG = "MyGcmListenerService";
    private String message_id = "";
    private String type = "";

    @Override
    public void onMessageReceived(RemoteMessage message) {
        String sale_id = "";
        Object obj = message.getData().get("sale_ID");
        if (obj != null) {
            sale_id = obj.toString();
        }
        String message_type = "";
        obj = message.getData().get("type");
        if (obj != null) {
            message_type = obj.toString();
        }

        SharedPreferences sharedPref = getSharedPreferences("myPreferences", Context.MODE_PRIVATE);
        message_id = sharedPref.getString("sales_uuid","-");
        type = sharedPref.getString("message_type","-");


        if (!(message_id.equals(sale_id) && type.equals(message_type))) {
            //String image = message.getNotification().getIcon();
            String title = message.getNotification().getTitle();
            if (title == null){
                title = "title notification";
            }
            String text = message.getNotification().getBody();
            if (text == null){
                text = "body text";
            }
            String sound = message.getNotification().getSound();
            String prov_uid = "";
            obj = message.getData().get("prov_Uid");
            if (obj != null) {
                prov_uid = obj.toString();
            }
            SharedPreferences.Editor editor = sharedPref.edit();
            editor.putString("sales_uuid",sale_id);
            editor.putString("message_type",message_type);
            editor.commit();
            this.sendNotification(new NotificationData(0, title, text, sound));
        }
    }

    /**
     * Create and show a simple notification containing the received GCM message.
     *
     * @param notificationData GCM message received.
     */
    private void sendNotification(NotificationData notificationData) {

        Intent intent = new Intent(this, MainActivity.class);
        intent.putExtra(NotificationData.TEXT, notificationData.getTextMessage());

        intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
        PendingIntent pendingIntent = PendingIntent.getActivity(this, 0 /* Request code */, intent,
                PendingIntent.FLAG_ONE_SHOT);

        NotificationCompat.Builder notificationBuilder = null;
        try {


            notificationBuilder = new NotificationCompat.Builder(this)
                    .setSmallIcon(R.mipmap.ic_launcher)
                    .setContentTitle(URLDecoder.decode(notificationData.getTitle(), "UTF-8"))
                    .setContentText(URLDecoder.decode(notificationData.getTextMessage(), "UTF-8"))
                    .setAutoCancel(true)
                    .setSound(RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION))
                    .setContentIntent(pendingIntent);

        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }

        if (notificationBuilder != null) {
            NotificationManager notificationManager =
                    (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
            notificationManager.notify(notificationData.getId(), notificationBuilder.build());
        } else {
            Log.d(TAG, "Não foi possível criar objeto notificationBuilder");
        }
    }
}

先谢谢你的帮助。