chat-rooms | Real time public/private chat application using spring boot | Websocket library

According to the Best Practices section of the official Firestore documentation:

You should always try to keep the number of snapshot listeners per client under 100.

Also you should keep in mind some more generic limits and quotas such as:

The maximum concurrent connections for mobile/web clients per database = 1,000,000

I would generally go with the approach of "Every chat room has a subcollection of messages. And every new message is a separate document in this subcollection." This has several advantages: It's easy to add or edit individual messages, and you can perform a number of different queries (like "Grab the 20 most recent messages")

The biggest drawback, I suppose, is that if you find that new users are frequently going to be entering your chat and will want to see the entire chat history of the room up until they joined, that would result in a large number of database reads. Realistically, though, I don't know how often that would happen in real life, and you could mitigate this by using pagination to grab your historical chat in batches.

With socket.io you generally only need to do a socket.join() on the room you want them in, which can be your dynamic room name. From there, you can just emit an event to the room.

One way to think about contexts is to view them as a layer of abstraction when you are designing your app. As it is put in the docs,

Phoenix projects are structured like Elixir and any other Elixir project – we split our code into contexts. A context will group related functionality, such as posts and comments, often encapsulating patterns such as data access and data validation. By using contexts, we decouple and isolate our systems into manageable, independent parts.

Models themselves with their underlying schema are therefore the units which you group into contexts. Models can have more fine-grained api which is necessary for their inner workings. Contexts in turn only expose methods which are useful to other application components or contexts, thus hiding the underlying implementation detail of the models.

It is not necessary to extend the context boundary down through the models level for absolute isolation. Instead you create your schema as usual, with all the many-to-many relations you need on the models. Then implement whatever low-level methods on the models directly. Put in the context only those methods which are either public api of the context or private methods touching more than one model.

UPDATE

In your scenario you might have e.g. Chats context where you put the rooms method. Its signature might be e.g. Chats.rooms_of(user). Repo.get() also goes to the context as, e.g. def get(id), do: Repo.get(User, id). The models end up containing changesets, validation methods, private methods with no dependencies to other models. The context in turn gets most of the group's publicly available business logic methods.

You don't need to loop over the JSON objects here, using jq, you could just interpolate the variable inside each object and do your logic as needed. Since the fields in the JSON could contain spaces between them using a custom delimiter | to split them and use that in the read command of the bash loop

There are two android apk available for WebRTC, appRtcDemo and webRtcDemo. appRtcDemo apk can be used for android device to browser connectivity. You need to provide room id to connect to one room. If you are the room initiator then you have to enter -1. If you want to connect two android device then you have to compile and install webRtcDemo apk. This apk interface provide place to enter ip address of another device and vice versa then both device will be connected.

Please go through -> http://www.webrtc.org/reference/getting-started

For more information. Both the apks i've compiled and installed and checked how it works.

I was able to make calls successfully between two android device using webrtcdemo. But I tested using WLAN of my office network. I did not use it further because I was using apprtcdemo for app reference. My suggestion is when you enter remote ip in webrtcdemo,just check if loop-back is unchecked. I guess for you loop-back is enabled, so you are receiving your own video packet, though you have entered remote ip. Make sure loop-back is disabled while making call.