Not able to make network calls while device is locked

[HugoHeneault]

I'm using latest https://github.com/phonegap/phonegap-plugin-push to get some VoIP notifications. It's running well when the phone is unlocked even when the app has been killed.

But when I lock the phone, I got the cordova-call screen showing, but on answer my socket.io is not able to connect.

I already opened an issue on the plugin push repo (phonegap/phonegap-plugin-push#2245) but I think it's more related to CordovaCall than push plugin...

Did anyone get the calls working with webrtc while the screen is locked?

Here is a sample of my code:

pushObject.on('notification').subscribe(async (data: any) => {
    // even with app force closed, xcode shows this code in logs
    console.log("Push on notification", data);
    
    if (this.platform.is('ios')) {
         cordova.plugins.CordovaCall.receiveCall(data.additionalData.username);
    }
}


cordova.plugins.CordovaCall.on('answer', async () => {
     const socket = io(ENV.API_URL, {
          port: ENV.API_PORT,
          query: 'test'
     });

     socket.on('connected', () => {
          // this code never runs if the screen is locked
          // if we check in network tabs with safari open, we can see an infinite loading socket.io request
          console.log('connected');
     });
});

I need to create a socket.io connection to get ice and descriptions...

[HugoHeneault]

Maybe there is a way to force device unlocking before answering?

[D-Marc1]

This is definitely not related to CordovaCall. PushKit was specifically made to allow VoIP apps to wake up the app and run code for a maximum of 30 seconds.

There's a few things I'm confused about your code. Why are you using async for cordova.plugins.CordovaCall.on('answer') and pushObject.on('notification') when there's no await? Why is socket.on('connected') nested inside of cordova.plugins.CordovaCall.on('answer')? As a rule of thumb, you shouldn't nest event handlers.

[dmarcs]

I agree with @D-Marc1. Your code should look like this

pushObject.on('notification').subscribe(async (data: any) => {
    // even with app force closed, xcode shows this code in logs
    console.log("Push on notification", data);
    
    if (this.platform.is('ios')) {
         cordova.plugins.CordovaCall.receiveCall(data.additionalData.username);
    }
}

const socket = io(ENV.API_URL, {
    port: ENV.API_PORT,
    query: 'test'
});

socket.on('connected', () => {
    // this code never runs if the screen is locked
    // if we check in network tabs with safari open, we can see an infinite loading socket.io request
    console.log('connected');
});

cordova.plugins.CordovaCall.on('answer', async () => {
});

[HugoHeneault]

So, some clarification (sorry guys my code might be misunderstood without context):

• I'm using async because I need to load user token from an async function, but I removed this line for clarity purposes.
• The socket is only used to handle Icecandidates and some messages for webrtc. It isn't for long-time connection, only for in-call messages. After the call, the socket is closed.

Even if I try to load something else than opening a socket (like load a 2ko json file), the connection is blocked. :(

If you have a way to make requests during the 30s after VoIP push notifications, I'd like to know what you're doing to get it working 🙂

[D-Marc1]

I'd suggest using this plugin instead of PhoneGap Push for PushKit. Other than that, I'm sorry, but I'm honestly not sure what else to tell you. There's nothing special you need to do to make it work. I'd suggest trying to get PushKit to work first, and then worry about it integrating it with this plugin. The issue is likely how you're using Socket.io

[dmarcs]

I'm guessing that your code opens the socket connection too late. You probably need to open it earlier, and not in the callback.

[HugoHeneault]

So you're able to make connection requests going through network with pushkit on your side?

Because I'm using the latest https://github.com/phonegap/phonegap-plugin-push which handles VoIP notifications for iOS since phonegap/phonegap-plugin-push#2194 has been merged... And pushkit seems to be working great (waking app even if it was locked, even with screen locked...)

I tried to open it at the exact moment when the VoIP notification arrives, but it's still not working :(

Thank you guys for your support!

[dmarcs]

I really think that you need to open the socket connection outside of onAnswer. You can check web inspector to see if your socket is connected. I have a demo video chat app that uses CordovaCall, the PushKit plugin that @D-Marc1 mentioned, iosRTC, and Firebase as the signaling server. It works perfectly even when the screen is locked and the app is closed. If I switch to Node.js, I'm sure it will still work.

Try making the socket connection when you first open the app, and let me know if that still doesn't work.

[HugoHeneault]

I'll try it and come back to you. I'm pretty sure I already tried opening the socket when the VoIP notification arrives. But I'll let you know.

Thanks for your tips.

[dmarcs]

@HugoHeneault Did you try opening the socket before the VOIP notification arrives? I would open the socket as soon as the app starts.

[D-Marc1]

The guys at Socket.IO were nice enough to provide a nice tutorial on how to use it with Cordova. I know that you want to start the socket connection only when a user sends or receives a call, but I don't think that's possible, to my knowledge. You should start the socket connection as soon as you open the app.

[HugoHeneault]

The socket closes when the device is locked, after a few minutes. This is due to the way ios handles memory savings.

Coming back to my first question: did you guys manage to download content while receiving the VoIP notification? I don't think the issue is socket.io related, as I have the same issue if I try to make xhr requests or download content at the moment the notification is received...

[D-Marc1]

This is without a doubt not a CordovaCall issue, as it's simply the native call UI and nothing more. You're combining CallKit, PushKit to wake up your app and using Socket.IO for your signaling server. I don't understand why you think it's related to this plugin at all.