I was developing the chat app in flutter using firestore, the users successfully chat one-to-one. but I also want to send the notification to the user that someone sends him/her a message. For that I decided to use the cloud messaging service of firebase, but how can I check that the user read the message or not.
There is nothing built into Cloud Firestore to track which user has read a specific document already.
The two most common approaches that I know of are:
To track for each individual message and each individual user whether they have read it, so by keeping a list of the user IDs in each message document. While this potentially stores a lot of extra data, it is the most direct mapping of your use-case.
In most chat apps though, tracking of what messages each user has read is done as an "up to here". So if the user has read all messages up until a certain one or a certain time, the assumption is that they've also read all the messages before that one/moment.
For this model you can instead just keep a single document ID or timestamp for each user (i.e. readUpTo), instead of having to mark each message for each user that has read it. In your UI, you then determine whether to show each message as unread based on the message ID/timestamp compared to the timestamp of readUpTo.
Related
Using Firestore.
Let's say I have a chat app, and once a message is sent, I want to aggregate it to the user's document, which has a "last message" field.
The motivation is to show next to this user's widget the last message sent.
One way to achieve that is using a Cloud Function: listen to changes on the messages collection / document, and copy that data to the user's document.
Another way would be to use the client SDK and write the last message data to the user's document when adding this message to the messages collection / document.
My questions is what are the pros (and cons if any) of using a Cloud Function for that (and in general for aggregating data)?
I have this chat structure for groups and private in real time, is there any way to structure to get the images and names of the people who chat? currently using UserIds I do a separate query to get it, but if someone changes their name or image it won't update.
You typically would start a RTDB listener for the nodes of the RTDB that contain the information for each of the users. Alternatively, you could copy all of the relevant user information into "current chats" and if a user changes their profile information you could also copy that new information into any "current chat" sessions.
In my app, I maintain user profile information in a profile collection in Firestore, and maintain the chat details in RTDB. So I have a realtime listener for the chat (RTDB) and a realtime listener for firestore.collection('profile').where('uid', 'in', arrayOfUserIDsInChat).
(Currently the way I have things, I am limited to the number of user profiles I can listen to ... in is limited to 10 ... but that is sufficient for my current requirements)
I am making a chess app which has a Firebase backend, i am using cloud firestore and cloud functions. basically i am using node 8 to avoid billing issues on cloud functions, i can call and trigger, but i can't wrap my head about how to make an action happen on another device instead of on my own.
After authenticating and logging in, the user gets into a lobby which is a tableViewController and there are shown only the users that are currently logged in.
What i want to achieve is by tapping on a certain row the user that got the tap on it gets an alert shown for him which states whether he accepts the challenge or he declines it. Based on that i proceed to the game or do something else.
The question is though how to make this alert trigger on the other user's device?
Also i've seen some posts that it can be done with snapshotListener on a document, but again i run into the problem of understanding how to trigger the alert on another device. If you've got some other good ideas please share!
Thank you for any feedback!
I think snapshot listeners are really the only way to go. You could use other Firebase services but those aren’t the right tools for the job. Consider creating a collection, maybe call it requests:
[requests]
<userId-userId> (recipientUserId-initiatorUserId)
initiator: string
recipient: string
date: date
Each user has a snapshot listener that listens to this collection where their own userId is equal to recipient. You can add a date field to sort the list by most recent, for example. When a user wants to challenge another user, all they need to do is create a document in this collection:
<userId-userId> (recipientUserId-initiatorUserId)
initiator: myUserId
recipient: theirUserId
date: now
And the recipient's client will instantly see this document.
You could include dressing data in this document, like the initiator's display name or a path to their avatar. But this data may be stale by the time it's rendered so the alternative is to fetch the dressing data from the database using the userId. You could also auto-gen the document ID but if you configure it (like this), it can make operations like deleting simpler. You could also configure the userIds to be alphanumerical so only one request can exist between two users; but if they requested each other at the same time, one would overwrite the other and you'd have to handle that potential edge case. There are lots of things to consider but this is the starting point.
Using these three tools, I'm trying to think of the best way to notify a user when the other user in a chat sends them a message (using APNs).
Would it be reasonable to store (and always update to newest value) the fcm registration token as a field under the user document in firestore, then in cloud functions, create a trigger to respond to new messages being sent (where each message is a document)? Then in order to determine which device to send it to, we use the registration token field?
Is there a better way to do this?
I'm trying to implement chat for my webapp with following features:
When user logs in he should see a number of unread messages (which is both offline messages and "unseen", I will explain "unseen" in next step).
When user is anywhere in the app but on chat window he should be notified that he has a new message. Message should be marked "unseen" and must be added to the count of unread messages.
The first point is quite easily achieved using XEP-0013: Flexible Offline Message Retrieval. So I can retrieve offline messages and when I'm sure user has seen them - I remove them from unread list. But the problem is: how do I achieve same thing for "unseen" messages?
In short what I need is: any message should be marked as offline, unless user sees it and it's removed from the list by explicit request.
Can I achieve that with XMPP and how do I do that?
Thanks in advance.
What you are trying to do is to basically store a counter of unseen stuff in your account. I think you do not need flexible offline retrieval as when you connect the messages would simply become unseen. You thus only have to deal with one case: Unseen.
I will reply from the perspective of ejabberd, that I know better as one of the developer: I would use private storage to store your current state of unseen count and conversation.