Obfuscation problem with AppUserTurnstile event

[yunikkk]

Configuration

• SDK Version - 4.7.0

Steps to Reproduce
We've been facing an issue with MAU calculation from Chinese customer (Sogou) for some time.
Turned out, telemetry library does not expose proguard config to keep AppUserTurnstile from obfuscation, in fact none of the classes from com.mapbox.android.telemetry package are being kept via proguard config.

So if user of some library (eg. Vision), which in turn uses Telemetry is not explicitly keeping telemetry classes from proguard, AppUserTurnstile will be obfuscated, and then converted to JSON with wrong schema, eg.

[
  {
    "c": "appUserTurnstile",
    "d": "2020-02-20T18:58:22.326+0300",
    "e": "cbff5455-344f-42ba-96a7-6c542ca3255a",
    "enabled.telemetry": true,
    "g": "B2N_sprout",
    "h": "MapboxVision",
    "i": "0.12.0",
    "j": "Nokia 7 plus",
    "k": "Android - 10",
    "l": null
  }
]

Such JSON will then fail to be processed on server so user won't be calculated as MAU.

BTW, you can notice that "enabled.telemetry" is not renamed due to explicit annotation that is used by gson @SerializedName("enabled.telemetry").

Several other mapbox libraries contain specific Telemetry related proguard exclusion configs, eg. https://github.com/mapbox/mapbox-navigation-android/blob/master/libandroid-navigation/proguard-consumer.pro. So users on Navigation won't have issue with MAU calculation.

At the same time I haven't found same config at Maps proguard so I wonder if it's possible that maps users may have similar issues that we have in Vision with missing MAU when obfuscation is turned on?

Also I've not checked further but it seems other Events may have similar issues with gson serialization.

Expected
Telemetry sends events with correct schema even if obfuscation is turned on

cc @kiryldz

[alfwatt]

Looks like we need:

• update to the proguard config to stop our symbols from getting mangled
• integration test which runs the code through any popular obfuscators our customers are using
• update to the documentation to make a note about obfuscation issues

[yunikkk]

@mapbox/maps-android could anyone please check that Maps actually keeps telemetry classes from obfuscation at the moment with current telem releases?

[tobrun]

I don't think that is the case. @Chaoba can you run point on fixing this for mapbox-gl-native-android?

[alfwatt]

@mapbox/maps-android can ya'll make a copy of this issue for the parallel work in Maps?

We should also invite @mapbox/navigation to this obscure party to make sure we have integration tests for all the SDKs that cover these obfuscation issues.

[zugaldia]

@mapbox/maps-android can ya'll make a copy of this issue for the parallel work in Maps?

This was addressed by mapbox/mapbox-gl-native-android#194 (thanks @Chaoba!)

[tobrun]

Small update for map side of things. We have a 9.1.0-alpha.1 version out with latest events library + proguard config on our end. We won't be backporting events library to older version but will include a proguard config to make sure we aren't obfuscating telemetry. We are planning a 9.0.1 and 8.7.3 with these changes.

[alfwatt]

@yunikkk please verify that these changes are working for you in the latest version of the Telemetry SDK and close the ticket if you believe we've addressed the issue completely

[yunikkk]

@alfwatt we've shipped new build with the updated telemetry inside and can confirm fix is working! Closing the issue

[Guardiola31337]

👀 mapbox/mapbox-gl-native-android#306 cc @zugaldia