[Android] Add tracing interceptor

Author: FranAguilera

Cargo.lock

@@ -53,6 +53,8 @@ class OkHttpEventListenerMethodVisitor(
     ) {
     private val captureOkHttpEventListenerFactory =
         "io/bitdrift/capture/network/okhttp/CaptureOkHttpEventListenerFactory"
+    private val captureOkHttpTracingInterceptor =
+        "io/bitdrift/capture/network/okhttp/CaptureOkHttpTracingInterceptor"
 
     override fun onMethodEnter() {
         super.onMethodEnter()
@@ -64,6 +66,8 @@ class OkHttpEventListenerMethodVisitor(
     }
 
     private fun addOverwritingEventListener() {
+        addTracingInterceptor()
+
         // Add the following call at the beginning of the constructor with the Builder parameter:
         // builder.eventListenerFactory(new CaptureOkHttpEventListenerFactory());
 
@@ -95,9 +99,12 @@ class OkHttpEventListenerMethodVisitor(
             "(Lokhttp3/EventListener\$Factory;)Lokhttp3/OkHttpClient\$Builder;",
             false,
         )
+        visitInsn(Opcodes.POP)
     }
 
     private fun addProxyingEventListener() {
+        addTracingInterceptor()
+
         // Add the following call at the beginning of the constructor with the Builder parameter:
         // builder.eventListenerFactory(new CaptureOkHttpEventListenerFactory(builder.eventListenerFactory));
 
@@ -141,5 +148,35 @@ class OkHttpEventListenerMethodVisitor(
             "(Lokhttp3/EventListener\$Factory;)Lokhttp3/OkHttpClient\$Builder;",
             false,
         )
+        visitInsn(Opcodes.POP)
+    }
+
+    private fun addTracingInterceptor() {
+        // Add the following call at the beginning of the constructor with the Builder parameter:
+        // builder.addInterceptor(new CaptureOkHttpTracingInterceptor());
+
+        // OkHttpClient.Builder is the parameter, retrieved here
+        visitVarInsn(Opcodes.ALOAD, 1)
+
+        // Create CaptureOkHttpTracingInterceptor instance
+        visitTypeInsn(Opcodes.NEW, captureOkHttpTracingInterceptor)
+        visitInsn(Opcodes.DUP)
+        visitMethodInsn(
+            Opcodes.INVOKESPECIAL,
+            captureOkHttpTracingInterceptor,
+            "<init>",
+            "()V",
+            false,
+        )
+
+        // Call addInterceptor(Interceptor)
+        visitMethodInsn(
+            Opcodes.INVOKEVIRTUAL,
+            "okhttp3/OkHttpClient\$Builder",
+            "addInterceptor",
+            "(Lokhttp3/Interceptor;)Lokhttp3/OkHttpClient\$Builder;",
+            false,
+        )
+        visitInsn(Opcodes.POP)
     }
 }

platform/jvm/capture-plugin/src/main/kotlin/io/bitdrift/capture/instrumentation/okhttp/visitor/OkHttpEventListenerMethodVisitor.kt

@@ -225,6 +225,14 @@ object Capture {
         val deviceId: String?
             get() = logger()?.deviceId
 
+        /**
+         * Whether workflow-controlled tracing is currently active for this session.
+         * Returns `null` prior to SDK start.
+         */
+        @JvmStatic
+        val isTracingActive: Boolean?
+            get() = logger()?.isTracingActive
+
         /**
          * Defines the initialization of a new session within the currently running logger
          * If no logger is started, this is a no-op.

platform/jvm/capture/src/main/kotlin/io/bitdrift/capture/Capture.kt

@@ -111,6 +111,11 @@ internal object CaptureJniLibrary : IBridge, IStreamingReportProcessor {
      */
     external fun getDeviceId(loggerId: Long): String?
 
+    /**
+     * Returns true when workflow-controlled tracing is active for the current session.
+     */
+    external fun isTracingActive(loggerId: Long): Boolean
+
     /**
      * Adds a field that should be attached to all logs emitted by the logger going forward.
      * If a field with a given key has already been registered with the logger, its value is

platform/jvm/capture/src/main/kotlin/io/bitdrift/capture/CaptureJniLibrary.kt

@@ -37,6 +37,11 @@ interface ILogger {
      */
     val deviceId: String
 
+    /**
+     * Whether workflow-controlled tracing is currently active for this session.
+     */
+    val isTracingActive: Boolean
+
     /**
      * Defines the initialization of a new session within the current logger.
      */

platform/jvm/capture/src/main/kotlin/io/bitdrift/capture/ILogger.kt

@@ -0,0 +1,27 @@
+// capture-sdk - bitdrift's client SDK
+// Copyright Bitdrift, Inc. All rights reserved.
+//
+// Use of this source code is governed by a source available license that can be found in the
+// LICENSE file or at:
+// https://polyformproject.org/wp-content/uploads/2020/06/PolyForm-Shield-1.0.0.txt
+
+package io.bitdrift.capture
+
+import io.bitdrift.capture.common.RuntimeConfig
+import io.bitdrift.capture.common.RuntimeFeature
+
+internal interface IRuntimeProvider {
+    fun isRuntimeFeatureEnabled(feature: RuntimeFeature): Boolean
+
+    fun getRuntimeConfigValue(config: RuntimeConfig): Int
+}
+
+internal object CaptureRuntimeProvider : IRuntimeProvider {
+    override fun isRuntimeFeatureEnabled(feature: RuntimeFeature): Boolean =
+        getLoggerProvider()?.isRuntimeFeatureEnabled(feature) ?: feature.defaultValue
+
+    override fun getRuntimeConfigValue(config: RuntimeConfig): Int =
+        getLoggerProvider()?.getRuntimeConfigValue(config) ?: config.defaultValue
+
+    private fun getLoggerProvider(): IRuntimeProvider? = Capture.logger() as? IRuntimeProvider
+}

platform/jvm/capture/src/main/kotlin/io/bitdrift/capture/IRuntimeProvider.kt

@@ -16,6 +16,7 @@ import androidx.lifecycle.ProcessLifecycleOwner
 import io.bitdrift.capture.attributes.ClientAttributes
 import io.bitdrift.capture.attributes.NetworkAttributes
 import io.bitdrift.capture.common.IWindowManager
+import io.bitdrift.capture.common.RuntimeConfig
 import io.bitdrift.capture.common.RuntimeFeature
 import io.bitdrift.capture.common.WindowManager
 import io.bitdrift.capture.error.ErrorReporterService
@@ -90,7 +91,8 @@ internal class LoggerImpl(
     private val eventListenerDispatcher: CaptureDispatchers.CommonBackground = CaptureDispatchers.CommonBackground,
     windowManager: IWindowManager = WindowManager(errorHandler),
 ) : IInternalLogger,
-    ICompletedReportsProcessor {
+    ICompletedReportsProcessor,
+    IRuntimeProvider {
     @OptIn(ExperimentalBitdriftApi::class)
     internal val webViewConfiguration: WebViewConfiguration? = configuration.webViewConfiguration
 
@@ -311,6 +313,9 @@ internal class LoggerImpl(
     override val deviceId: String
         get() = CaptureJniLibrary.getDeviceId(this.loggerId) ?: "unknown"
 
+    override val isTracingActive: Boolean
+        get() = CaptureJniLibrary.isTracingActive(this.loggerId)
+
     override fun startNewSession() {
         CaptureJniLibrary.startNewSession(this.loggerId)
     }
@@ -538,6 +543,10 @@ internal class LoggerImpl(
         )
     }
 
+    override fun isRuntimeFeatureEnabled(feature: RuntimeFeature): Boolean = runtime.isEnabled(feature)
+
+    override fun getRuntimeConfigValue(config: RuntimeConfig): Int = runtime.getConfigValue(config)
+
     override fun logSessionReplayScreenshot(
         fields: Array<Field>,
         duration: Duration,

platform/jvm/capture/src/main/kotlin/io/bitdrift/capture/LoggerImpl.kt

@@ -16,6 +16,7 @@ import io.bitdrift.capture.network.HttpRequestMetrics
 import io.bitdrift.capture.network.HttpResponse
 import io.bitdrift.capture.network.HttpResponseInfo
 import io.bitdrift.capture.network.HttpUrlPath
+import io.bitdrift.capture.network.okhttp.CaptureOkHttpTracingInterceptor.Companion.TRACE_ID_HEADER
 import okhttp3.Call
 import okhttp3.Connection
 import okhttp3.EventListener
@@ -380,7 +381,10 @@ internal class CaptureOkHttpEventListener internal constructor(
                 response = httpResponse,
                 durationMs = (clock.elapsedRealtime() - callStartTimeMs),
                 metrics = getMetrics(),
-                extraFields = responseExtraFieldsProvider.provideExtraFields(response),
+                extraFields =
+                    responseExtraFieldsProvider
+                        .provideExtraFields(response)
+                        .plus(traceIdFromRequestHeaders(request)),
             )
 
         logger?.log(httpResponseInfo)
@@ -421,10 +425,16 @@ internal class CaptureOkHttpEventListener internal constructor(
                 response = httpResponse,
                 durationMs = (clock.elapsedRealtime() - callStartTimeMs),
                 metrics = getMetrics(),
+                extraFields = traceIdFromRequestHeaders(request),
             )
         logger?.log(httpResponseInfo)
     }
 
+    private fun traceIdFromRequestHeaders(request: Request): Map<String, String> {
+        val traceId = request.header(TRACE_ID_HEADER) ?: return emptyMap()
+        return mapOf(CaptureTracing.TRACE_ID_FIELD_KEY to traceId)
+    }
+
     override fun canceled(call: Call) {
         runCatching { targetEventListener?.canceled(call) }
     }

platform/jvm/capture/src/main/kotlin/io/bitdrift/capture/network/okhttp/CaptureOkHttpEventListener.kt

@@ -0,0 +1,60 @@
+// capture-sdk - bitdrift's client SDK
+// Copyright Bitdrift, Inc. All rights reserved.
+//
+// Use of this source code is governed by a source available license that can be found in the
+// LICENSE file or at:
+// https://polyformproject.org/wp-content/uploads/2020/06/PolyForm-Shield-1.0.0.txt
+
+package io.bitdrift.capture.network.okhttp
+
+import androidx.annotation.VisibleForTesting
+import io.bitdrift.capture.Capture
+import io.bitdrift.capture.CaptureRuntimeProvider
+import io.bitdrift.capture.IRuntimeProvider
+import io.bitdrift.capture.common.RuntimeConfig
+import okhttp3.Interceptor
+import okhttp3.Response
+
+/**
+ * Injects tracing headers into outgoing requests when Capture tracing is active for this session.
+ *
+ * The propagation format is resolved from a runtime config flag.
+ */
+class CaptureOkHttpTracingInterceptor
+    @VisibleForTesting
+    internal constructor(
+        private val runtimeProvider: IRuntimeProvider,
+    ) : Interceptor {
+        constructor() : this(CaptureRuntimeProvider)
+
+        override fun intercept(chain: Interceptor.Chain): Response {
+            val propagationMode = getPropagationMode()
+
+            val request = chain.request()
+            if (propagationMode == CaptureTracing.TracePropagationMode.OFF || Capture.logger()?.isTracingActive == false) {
+                return chain.proceed(request)
+            }
+
+            val trace = CaptureTracing.newTraceContext()
+            val requestBuilder = request.newBuilder()
+            val propagationValue =
+                when (propagationMode) {
+                    CaptureTracing.TracePropagationMode.W3C -> trace.traceparent
+                    CaptureTracing.TracePropagationMode.B3 -> trace.b3
+                    CaptureTracing.TracePropagationMode.OFF -> return chain.proceed(request)
+                }
+            val headerName = propagationMode.headerName ?: return chain.proceed(request)
+            requestBuilder.header(headerName, propagationValue)
+            requestBuilder.header(TRACE_ID_HEADER, trace.traceId)
+            return chain.proceed(requestBuilder.build())
+        }
+
+        private fun getPropagationMode(): CaptureTracing.TracePropagationMode =
+            CaptureTracing.TracePropagationMode.fromRuntimeValue(
+                runtimeProvider.getRuntimeConfigValue(RuntimeConfig.TRACE_PROPAGATION_MODE),
+            )
+
+        internal companion object {
+            internal const val TRACE_ID_HEADER = "x-capture-span-trace-field-trace_id"
+        }
+    }

platform/jvm/capture/src/main/kotlin/io/bitdrift/capture/network/okhttp/CaptureOkHttpTracingInterceptor.kt

@@ -0,0 +1,60 @@
+// capture-sdk - bitdrift's client SDK
+// Copyright Bitdrift, Inc. All rights reserved.
+//
+// Use of this source code is governed by a source available license that can be found in the
+// LICENSE file or at:
+// https://polyformproject.org/wp-content/uploads/2020/06/PolyForm-Shield-1.0.0.txt
+
+package io.bitdrift.capture.network.okhttp
+
+import java.security.SecureRandom
+
+internal object CaptureTracing {
+    internal const val TRACE_ID_FIELD_KEY = "_trace_id"
+
+    /** Supported trace propagation modes. */
+    internal enum class TracePropagationMode(
+        internal val runtimeValue: Int,
+        internal val headerName: String?,
+    ) {
+        /** Disable trace header injection. */
+        OFF(0, null),
+
+        /** W3C Trace Context format via the `traceparent` header. */
+        W3C(1, "traceparent"),
+
+        /** Zipkin B3 single-header format via the `b3` header. */
+        B3(2, "b3"),
+        ;
+
+        internal companion object {
+            fun fromRuntimeValue(value: Int): TracePropagationMode = entries.firstOrNull { it.runtimeValue == value } ?: OFF
+        }
+    }
+
+    private val random = SecureRandom()
+
+    internal data class TraceContext(
+        val traceId: String,
+        val spanId: String,
+        val traceparent: String, // This is W3C header format
+        val b3: String, // B3 header format by Zipkin
+    )
+
+    internal fun newTraceContext(): TraceContext {
+        val traceId = randomHex(16)
+        val spanId = randomHex(8)
+        return TraceContext(
+            traceId = traceId,
+            spanId = spanId,
+            traceparent = "00-$traceId-$spanId-01",
+            b3 = "$traceId-$spanId-1",
+        )
+    }
+
+    private fun randomHex(byteCount: Int): String {
+        val bytes = ByteArray(byteCount)
+        random.nextBytes(bytes)
+        return bytes.joinToString(separator = "") { "%02x".format(it) }
+    }
+}