[Bug]: Double reporting of background geolocation

[al-muammar]

Required Reading

• Confirmed

Plugin Version

4.16.9

Flutter Doctor

$ flutter doctor                                                                                                                                                                             11:46:11
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Mobile operating-system(s)

• iOS
• Android

Device Manufacturer(s) and Model(s)

SM-A525F

Device operating-systems(s)

Android 13

What happened?

Geolocation tracking turned-on twice and was sending coordinates twice to the server

Plugin Code and/or Config

It seems that there was a race condition and background geolocation start was called twice. At the same time our code looks as follows:

  Future<void> start() async {
    final state = await BackgroundGeolocation.state;
    if (state.enabled) {
      return;
    }
    await BackgroundGeolocation.start();
  }

Then one stream collecting background geolocation was actively sending everything to the server, the other one simply collected and saved to the local database. At some point the collecting stream started sending the data to the server and data duplication finished. It seems like a weird situation

Relevant log output

[christocracy]

The native SDK is implemented as a Singleton.

It is impossible to have two instances independently running and recording location.

[christocracy]

background geolocation start was called twice

You can call .start() a hundred times, the plug-in doesn’t care. It does not affect the performance of the plug-in.

Try it yourself and see.