Add tracing support

[FranAguilera]

What

Resolves BIT-7463, BIT-7462

Depends on bitdriftlabs/shared-core#412

Adds tracing support for Android (W3C, B3). The whole feature is controlled via runtime config client_config.trace.propagation_mode (frontend config will be tracing_features.trace_id_deep_link_url_template)

Android example for manual integration

private val okHttpClientManual: OkHttpClient =
        OkHttpClient
            .Builder()
            .addInterceptor(CaptureOkHttpTracingInterceptor()) // Add this interceptor to your okhttp client
            .eventListenerFactory(
                CaptureOkHttpEventListenerFactory(
                    requestFieldProvider = RetrofitUrlPathProvider(CustomRequestFieldProvider()),
                    responseFieldProvider = CustomResponseFieldProvider(),
                ),
            )
            .build()

If automatic instrumentation is enabled, no additional interceptor needs to be added (only apply gradle plugin flag)

bitdrift {
    instrumentation {
        automaticOkHttpInstrumentation = true
    }
}

For iOS, tracing works automatically when the URLSession integration is enabled with swizzling (default config). No additional setup required.

Verification

• JUnit tests

Manual

• In Android gradle-test-app. Use chucker to easily confirm visually the added headers to requests
• Set runtime flag to W3C, and setup a workflow to set tracing as active
• Configure runtime config values in staging
• gradle-test-app should append the required headers (for both auto/and manual okhttp calls)
• For auto instrumentation, use maven local and use the local version in gradle-test-app. Verify header are still appended

Android Manual	Android automatic (automaticOkHttpInstrumentation to true)
link	link

---

• CHANGELOG.md's "Unreleased" section has been updated, if applicable.

[github-actions]

Size Comparison Report (x86_64)

Metric	APK (KB)	SO (KB)
Baseline	3406	1280
Current	3406	1280
Difference	0	0

APK size unchanged. SO size unchanged.

[github-actions]

Android Benchmark Results

Device: PR: Emulator - Android SDK built for x86_64 (API 31) | main: Emulator - Android SDK built for x86_64 (API 31)

Note: Benchmarks run on emulator. Results may vary between runs and may differ from physical devices.

Allocations

Test	PR	main	Δ
logHttpNetworkLog50FieldsAndHeadersAndFieldProviders	924	919	+0.5%
logNotMatched5000Fields	10	10	0.0%
logNotMatchedNoFields	1	1	0.0%
trackSpansWithFields	140	138	+1.4%
trackSpansWithoutFields	55	56	-1.8%
webViewBridgeBridgeReady	61	60	+1.7%
webViewBridgeCustomLog	66	58	+13.8%
webViewBridgeInvalidJson	38	38	0.0%
webViewBridgeWebVitalCLS	177	175	+1.1%

Timing

Test	PR	main	Δ
logHttpNetworkLog50FieldsAndHeadersAndFieldProviders	240.04 us	273.66 us	-12.3%
logNotMatched5000Fields	2.48 ms	3.09 ms	-19.8%
logNotMatchedNoFields	446 ns	463 ns	-3.8%
trackSpansWithFields	484.45 us	615.34 us	-21.3%
trackSpansWithoutFields	7.95 us	8.66 us	-8.2%
webViewBridgeBridgeReady	8.48 us	8.03 us	+5.7%
webViewBridgeCustomLog	8.81 us	14.01 us	-37.1%
webViewBridgeInvalidJson	163.93 us	106.58 us	+53.8%
webViewBridgeWebVitalCLS	20.64 us	20.23 us	+2.0%

[FranAguilera]

Pending to consolidate both config values

[FranAguilera]

Actually will do this in a separate PR this is getting a bit noisy given the iOS changes as well

[snowp]

There's potentially a larger discussion to be had about how "tracing enabled" interacts with clients that already populate the headers and whether we can do something in that case but I wouldn't block this PR on it