Feature Value fails in multiprocess environment

[sameerjj]

I have a ForegroundService which requires a feature flag, I declare it to have a separate process in the manifest:
android:process=":location"

when I call
gb.feature("baseurl").value as String
it fails, despite it working in the main process.

[sameerjj]

sample initialization code:

val gb = GBSDKBuilder(
                apiKey = "sdk-key",
                hostURL = "https://cdn.growthbook.io/",
                networkDispatcher = DefaultGBNetworkClient(),
                attributes = mapOf("app_id" to appId),
                trackingCallback = { gbExperiment, gbExperimentResult ->
                    Log.d(TAG, "Variation Id: ${gbExperimentResult.variationId}")
                },
            ).initialize()
            
            val baseUrl = gb.feature("samplekey").value as String
            val legacyEndpoints = gb.feature("sampleflag").off
            

[Bohdan-Kim]

Hello @sameerjj !
Could you please give us more details about "fails".
Is it java.lang.NullPointerException?

[Bohdan-Kim]

Try to use
gb.feature("baseurl").value as String?
instead of
gb.feature("baseurl").value as String

[sameerjj]

Yes null pointer exception - the features don’t exist in that process (my guess would be the cache is in the memory of the other process but still marked as “saved “) The value is null so casting to optional doesn’t really solve the issue as the feature definitely exists and works in the main app Le mer. 8 mai 2024 à 14:40, Bohdan Kim ***@***.***> a écrit :

…

Try to use gb.feature("baseurl").value as String? instead of gb.feature("baseurl").value as String — Reply to this email directly, view it on GitHub <#103 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABVZP6KHJP73LTENSIBOF6LZBJWSZAVCNFSM6AAAAABHMA5DB6VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDCMBRGIYDIOJYGY> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[Bohdan-Kim]

@sameerjj It is not safe to cast. gb.feature("baseurl").value is null because it takes some time to get features from Backend. Some delay needed between SDK initialization and accessing the feature. The delay needed only for the first time. Once features have been got from Backend they will have been cached. We tried the code you provided. The features were not got because of cast to String.
One more point is make sure network request is allowed from the thread you are trying to get features.
Or maybe you want to initialize the SDK from main thread but to access features from another thread?

[sameerjj]

Hi @Bohdan-Kim, is there a way to know when the initialization is complete? .initialize() is synchronous in latest version 1.1.47

[sameerjj]

btw, I induced a delay of 1 second between initialize() and the use of the feature, and it still didn't work in the foreground service separate process. I also tried a retry mechanism. It simply doesn't load here.
Anyways, I'm just going to use my own cache, but there's definitely an issue here

[Bohdan-Kim]

The issue is hard to reproduce.

[Bohdan-Kim]

is there a way to know when the initialization is complete?
setRefreshHandler() in GBSDKBuilder class. setRefreshHandler() can be used to be notified about features refresh.

[Bohdan-Kim]

We tried just to wrap the code with thread {}. Everything works the same. We understand that this is not the foreground service.

[Bohdan-Kim]

It seems like we reproduced the issue.

[Bohdan-Kim]

This foreground service works fine for us:
https://gist.github.com/Bohdan-Kim/d2dd0f0871fe3019996e7adab368d79d

[sameerjj]

Hi @Bohdan-Kim, you would have to add to your manifest that it's a separate process as I mentioned

<service
            android:name="com.example.growthbookdemoapp.ForegroundService"
            android:exported="false"
            android:foregroundServiceType="location"
            android:process=":location" />

[Bohdan-Kim]

We followed your instruction and noticed that when foregroundServiceType and process attributes are applied the features list are not restored from cache.

[Bohdan-Kim]

The pull request was created according to this issue.
After merge in main branch there will be an option to pass Service context to the GrowthBook SDK. For similar issues we will ask to paste this line:

CachingAndroid.consumeContext(this)

where this is a reference to a Service instance.

[Bohdan-Kim]

We released v1.1.58 version of the SDK. The changes from pull request are available in v1.1.58