Android Firebase云功能通知

Question

我已设法设置firebase云功能以向主题发送通知.问题是它发送给所有用户,包括发件人,我如何设置我的云功能,以便它不向发送者显示通知？请帮忙？以下是我发送给主题的方式

exports.sendNotesNotification = functions.database.ref('/Notes/{pushId}')
    .onWrite(event => {
        const notes = event.data.val();

        const payload = {
                notification: {

                    username: notes.username,
                    title: notes.title,
                    body: notes.desc

                }

            }

            admin.messaging().sendToTopic("New_entry", payload)
            .then(function(response){
                console.log("Successfully sent notes: ", response);
            })
            .catch(function(error){
                console.log("Error sending notes: ", error);
            });
        }); 

Answer 1

从firebase的文档中,应该使用主题发送通知,以用于公开且不是时间关键的通知.在您的情况下,通知不是公开的,并且由于发件人也订阅了该特定主题,他也将收到通知.因此,如果您想避免向发件人发送通知,则必须从主题中取消订阅该发件人.

或者更好的解决方案是您应该使用FCM令牌将通知发送到单个设备.用于发送FCM令牌通知的node.js代码是

admin.messaging().sendToDevice(<array of tokens>, payload);

你可以从Android的FirebaseInstanceIdService的onTokenRefresh()方法获取设备令牌.

 @Override
    public void onTokenRefresh() {
        // Get updated InstanceID token.
        String refreshedToken = FirebaseInstanceId.getInstance().getToken();
        // TO DO: send token to your server or firebase database
}

更新:

将firebase标记存储到数据库现在您应该像这样构建数据库

   -users
      |-user1uid
      |   |-name //your choice
      |   |-email //your choice
      |   |-fcmTokens
      |        |-valueOftoken1:true
      |        |-valueOftoken2:true
   -notes
      |  |-notesId
      |      |-yourdata
      |      |-createdBy:uidofUser  //user who created note
      |
   -subscriptions       //when onWrite() will trigger we will use this to get UID of all subscribers of creator of "note". 
      |      |-uidofUser    
      |           |-uidofSubscriber1:true //user subscribe to notes written. by parent node uid
      |           |-uidofSubscriber2:true

在这里保存令牌在数据库是代码 onTokenRefresh()

 @Override
        public void onTokenRefresh() {
            // Get updated InstanceID token.
            String refreshedToken = FirebaseInstanceId.getInstance().getToken(); //get refreshed token
            FirebaseAuth mAuth = FirebaseAuth.getInstance();
            FirebaseUser user = mAuth.getCurrentUser(); //get currentto get uid
            if(user!=null){
            DatabaseReference mDatabase = FirebaseDatabase.getInstance().getReference().child("users").child(user.getUid()); // create a reference to userUid in database
            if(refreshedToken!=null) //
              mDatabase.child("fcmTokens").child(refreshedToken).setValue(true); //creates a new node of user's token and set its value to true.
            else
              Log.i(TAG, "onTokenRefresh: token was null");
    }
    Log.d(tag, "Refreshed token SEND TO FIREBASE: " + refreshedToken);
    }

当为该用户创建新令牌时,上述代码将在用户的fcmTokens中创建新节点.

node.js的一部分是检索用户令牌并向这些令牌发送通知.为了这

exports.sendNotesNotification = functions.database.ref('/Notes/{pushId}')
    .onWrite(event => {

        const notes = event.data.val();
        const createdby = notes.createdBy;
        const getAllSubscribersPromise = admin.database().ref(`/subscriptions/${createdby}/`).once('value'); // retrieving subscribers 

         const payload = {
                notification: {

                    username: notes.username,
                    title: notes.title,
                    body: notes.desc

                }

            }

        return getAllSubscribersPromise.then(result => {
        const userUidSnapShot = result; //results will have children having keys of subscribers uid.
        if (!userUidSnapShot.hasChildren()) {
          return console.log('There are no subscribed users to write notifications.'); 
        }
        console.log('There are', userUidSnapShot.numChildren(), 'users to send notifications to.');
        const users = Object.keys(userUidSnapShot.val()); //fetched the keys creating array of subscribed users

        var AllFollowersFCMPromises = []; //create new array of promises of TokenList for every subscribed users
        for (var i = 0;i<userUidSnapShot.numChildren(); i++) {
            const user=users[i];
            console.log('getting promise of user uid=',user);
            AllFollowersFCMPromises[i]= admin.database().ref(`/users/${user}/fcmToken/`).once('value');
        }

        return Promise.all(AllFollowersFCMPromises).then(results => {

            var tokens = []; // here is created array of tokens now ill add all the fcm tokens of all the user and then send notification to all these.
            for(var i in results){
                var usersTokenSnapShot=results[i];
                console.log('For user = ',i);
                if(usersTokenSnapShot.exists()){
                    if (usersTokenSnapShot.hasChildren()) { 
                        const t=  Object.keys(usersTokenSnapShot.val()); //array of all tokens of user [n]
                        tokens = tokens.concat(t); //adding all tokens of user to token array
                        console.log('token[s] of user = ',t);
                    }
                    else{

                    }
                }
            }
            console.log('final tokens = ',tokens," notification= ",payload);
            return admin.messaging().sendToDevice(tokens, payload).then(response => {
      // For each message check if there was an error.
                const tokensToRemove = [];
                response.results.forEach((result, index) => {
                    const error = result.error;
                    if (error) {
                        console.error('Failure sending notification to uid=', tokens[index], error);
                        // Cleanup the tokens who are not registered anymore.
                        if (error.code === 'messaging/invalid-registration-token' || error.code === 'messaging/registration-token-not-registered') {
                            tokensToRemove.push(usersTokenSnapShot.ref.child(tokens[index]).remove());
                        }
                    }
                    else{
                        console.log("notification sent",result);
                    }
                });

                return Promise.all(tokensToRemove);
            });

            return console.log('final tokens = ',tokens," notification= ",payload);
        });





            });
        }); 

我没有检查node.js部分让我知道你是否还有问题.