Automatically downsample transaction when system is under load (backpressure)

sentry-spring-boot-jakarta/src/test/kotlin/io/sentry/spring/boot/jakarta/it/SentrySpringIntegrationTest.kt

@@ -210,7 +210,9 @@ class SentrySpringIntegrationTest {
 
 @SpringBootApplication
 open class App {
-    private val transport = mock<ITransport>()
+    private val transport = mock<ITransport>().also {
+        whenever(it.isHealthy).thenReturn(true)
+    }
 
     @Bean
     open fun mockTransportFactory(): ITransportFactory {

sentry-spring-boot/src/test/kotlin/io/sentry/spring/boot/it/SentrySpringIntegrationTest.kt

@@ -210,7 +210,9 @@ class SentrySpringIntegrationTest {
 
 @SpringBootApplication
 open class App {
-    private val transport = mock<ITransport>()
+    private val transport = mock<ITransport>().also {
+        whenever(it.isHealthy).thenReturn(true)
+    }
 
     @Bean
     open fun mockTransportFactory(): ITransportFactory {

sentry-spring-jakarta/src/test/kotlin/io/sentry/spring/jakarta/EnableSentryTest.kt

@@ -6,8 +6,11 @@ import io.sentry.ITransportFactory
 import io.sentry.Integration
 import io.sentry.Sentry
 import io.sentry.SentryOptions
+import io.sentry.transport.ITransport
 import org.assertj.core.api.Assertions.assertThat
+import org.mockito.kotlin.any
 import org.mockito.kotlin.mock
+import org.mockito.kotlin.whenever
 import org.springframework.boot.context.annotation.UserConfigurations
 import org.springframework.boot.test.context.runner.ApplicationContextRunner
 import org.springframework.context.annotation.Bean
@@ -185,7 +188,9 @@ class EnableSentryTest {
     class AppConfigWithCustomTransportFactory {
 
         @Bean
-        fun transport() = mock<ITransportFactory>()
+        fun transport() = mock<ITransportFactory>().also {
+            whenever(it.create(any(), any())).thenReturn(mock<ITransport>())
+        }
     }
 
     @EnableSentry(dsn = "http://key@localhost/proj")

sentry-spring-jakarta/src/test/kotlin/io/sentry/spring/jakarta/webflux/SentryWebfluxIntegrationTest.kt

@@ -145,7 +145,9 @@ class SentryWebfluxIntegrationTest {
 @SpringBootApplication(exclude = [ReactiveSecurityAutoConfiguration::class, SecurityAutoConfiguration::class])
 open class App {
 
-    private val transport = mock<ITransport>()
+    private val transport = mock<ITransport>().also {
+        whenever(it.isHealthy).thenReturn(true)
+    }
 
     @Bean
     open fun mockTransportFactory(): ITransportFactory {

sentry-spring/src/test/kotlin/io/sentry/spring/EnableSentryTest.kt

@@ -6,8 +6,11 @@ import io.sentry.ITransportFactory
 import io.sentry.Integration
 import io.sentry.Sentry
 import io.sentry.SentryOptions
+import io.sentry.transport.ITransport
 import org.assertj.core.api.Assertions.assertThat
+import org.mockito.kotlin.any
 import org.mockito.kotlin.mock
+import org.mockito.kotlin.whenever
 import org.springframework.boot.context.annotation.UserConfigurations
 import org.springframework.boot.test.context.runner.ApplicationContextRunner
 import org.springframework.context.annotation.Bean
@@ -185,7 +188,9 @@ class EnableSentryTest {
     class AppConfigWithCustomTransportFactory {
 
         @Bean
-        fun transport() = mock<ITransportFactory>()
+        fun transport() = mock<ITransportFactory>().also {
+            whenever(it.create(any(), any())).thenReturn(mock<ITransport>())
+        }
     }
 
     @EnableSentry(dsn = "http://key@localhost/proj")

sentry-spring/src/test/kotlin/io/sentry/spring/webflux/SentryWebfluxIntegrationTest.kt

@@ -145,7 +145,9 @@ class SentryWebfluxIntegrationTest {
 @SpringBootApplication(exclude = [ReactiveSecurityAutoConfiguration::class, SecurityAutoConfiguration::class])
 open class App {
 
-    private val transport = mock<ITransport>()
+    private val transport = mock<ITransport>().also {
+        whenever(it.isHealthy).thenReturn(true)
+    }
 
     @Bean
     open fun mockTransportFactory(): ITransportFactory {

sentry-test-support/src/main/kotlin/io/sentry/test/Mocks.kt

@@ -2,19 +2,24 @@
 package io.sentry.test
 
 import io.sentry.ISentryExecutorService
+import io.sentry.backpressure.IBackpressureMonitor
 import org.mockito.kotlin.mock
 import java.util.concurrent.Callable
 import java.util.concurrent.Future
 
 class ImmediateExecutorService : ISentryExecutorService {
     override fun submit(runnable: Runnable): Future<*> {
-        runnable.run()
+        if (runnable !is IBackpressureMonitor) {
+            runnable.run()
+        }
         return mock()
     }
 
     override fun <T> submit(callable: Callable<T>): Future<T> = mock()
     override fun schedule(runnable: Runnable, delayMillis: Long): Future<*> {
-        runnable.run()
+        if (runnable !is IBackpressureMonitor) {
+            runnable.run()
+        }
         return mock<Future<Runnable>>()
     }
     override fun close(timeoutMillis: Long) {}

sentry/api/sentry.api

@@ -435,6 +435,7 @@ public final class io/sentry/Hub : io/sentry/IHub {
 	public fun getTransaction ()Lio/sentry/ITransaction;
 	public fun isCrashedLastRun ()Ljava/lang/Boolean;
 	public fun isEnabled ()Z
+	public fun isHealthy ()Z
 	public fun popScope ()V
 	public fun pushScope ()V
 	public fun removeExtra (Ljava/lang/String;)V
@@ -485,6 +486,7 @@ public final class io/sentry/HubAdapter : io/sentry/IHub {
 	public fun getTransaction ()Lio/sentry/ITransaction;
 	public fun isCrashedLastRun ()Ljava/lang/Boolean;
 	public fun isEnabled ()Z
+	public fun isHealthy ()Z
 	public fun popScope ()V
 	public fun pushScope ()V
 	public fun removeExtra (Ljava/lang/String;)V
@@ -578,6 +580,7 @@ public abstract interface class io/sentry/IHub {
 	public abstract fun getTransaction ()Lio/sentry/ITransaction;
 	public abstract fun isCrashedLastRun ()Ljava/lang/Boolean;
 	public abstract fun isEnabled ()Z
+	public abstract fun isHealthy ()Z
 	public abstract fun popScope ()V
 	public abstract fun pushScope ()V
 	public abstract fun removeExtra (Ljava/lang/String;)V
@@ -718,6 +721,7 @@ public abstract interface class io/sentry/ISentryClient {
 	public abstract fun flush (J)V
 	public abstract fun getRateLimiter ()Lio/sentry/transport/RateLimiter;
 	public abstract fun isEnabled ()Z
+	public fun isHealthy ()Z
 }
 
 public abstract interface class io/sentry/ISentryExecutorService {
@@ -1119,6 +1123,7 @@ public final class io/sentry/NoOpHub : io/sentry/IHub {
 	public fun getTransaction ()Lio/sentry/ITransaction;
 	public fun isCrashedLastRun ()Ljava/lang/Boolean;
 	public fun isEnabled ()Z
+	public fun isHealthy ()Z
 	public fun popScope ()V
 	public fun pushScope ()V
 	public fun removeExtra (Ljava/lang/String;)V
@@ -1665,6 +1670,7 @@ public final class io/sentry/Sentry {
 	public static fun init (Ljava/lang/String;)V
 	public static fun isCrashedLastRun ()Ljava/lang/Boolean;
 	public static fun isEnabled ()Z
+	public static fun isHealthy ()Z
 	public static fun popScope ()V
 	public static fun pushScope ()V
 	public static fun removeExtra (Ljava/lang/String;)V
@@ -1781,6 +1787,7 @@ public final class io/sentry/SentryClient : io/sentry/ISentryClient {
 	public fun flush (J)V
 	public fun getRateLimiter ()Lio/sentry/transport/RateLimiter;
 	public fun isEnabled ()Z
+	public fun isHealthy ()Z
 }
 
 public final class io/sentry/SentryCrashLastRunState {
@@ -2078,6 +2085,7 @@ public class io/sentry/SentryOptions {
 	public fun addOptionsObserver (Lio/sentry/IOptionsObserver;)V
 	public fun addScopeObserver (Lio/sentry/IScopeObserver;)V
 	public fun addTracingOrigin (Ljava/lang/String;)V
+	public fun getBackpressureMonitor ()Lio/sentry/backpressure/IBackpressureMonitor;
 	public fun getBeforeBreadcrumb ()Lio/sentry/SentryOptions$BeforeBreadcrumbCallback;
 	public fun getBeforeSend ()Lio/sentry/SentryOptions$BeforeSendCallback;
 	public fun getBeforeSendTransaction ()Lio/sentry/SentryOptions$BeforeSendTransactionCallback;
@@ -2156,6 +2164,7 @@ public class io/sentry/SentryOptions {
 	public fun isAttachThreads ()Z
 	public fun isDebug ()Z
 	public fun isEnableAutoSessionTracking ()Z
+	public fun isEnableBackpressureHandling ()Z
 	public fun isEnableDeduplication ()Z
 	public fun isEnableExternalConfiguration ()Z
 	public fun isEnablePrettySerializationOutput ()Z
@@ -2177,6 +2186,7 @@ public class io/sentry/SentryOptions {
 	public fun setAttachServerName (Z)V
 	public fun setAttachStacktrace (Z)V
 	public fun setAttachThreads (Z)V
+	public fun setBackpressureMonitor (Lio/sentry/backpressure/IBackpressureMonitor;)V
 	public fun setBeforeBreadcrumb (Lio/sentry/SentryOptions$BeforeBreadcrumbCallback;)V
 	public fun setBeforeSend (Lio/sentry/SentryOptions$BeforeSendCallback;)V
 	public fun setBeforeSendTransaction (Lio/sentry/SentryOptions$BeforeSendTransactionCallback;)V
@@ -2191,6 +2201,7 @@ public class io/sentry/SentryOptions {
 	public fun setDistinctId (Ljava/lang/String;)V
 	public fun setDsn (Ljava/lang/String;)V
 	public fun setEnableAutoSessionTracking (Z)V
+	public fun setEnableBackpressureHandling (Z)V
 	public fun setEnableDeduplication (Z)V
 	public fun setEnableExternalConfiguration (Z)V
 	public fun setEnablePrettySerializationOutput (Z)V
@@ -2821,6 +2832,24 @@ public final class io/sentry/UserFeedback$JsonKeys {
 	public fun <init> ()V
 }
 
+public final class io/sentry/backpressure/BackpressureMonitor : io/sentry/backpressure/IBackpressureMonitor, java/lang/Runnable {
+	public fun <init> (Lio/sentry/SentryOptions;Lio/sentry/IHub;)V
+	public fun getDownsampleFactor ()I
+	public fun run ()V
+	public fun start ()V
+}
+
+public abstract interface class io/sentry/backpressure/IBackpressureMonitor {
+	public abstract fun getDownsampleFactor ()I
+	public abstract fun start ()V
+}
+
+public final class io/sentry/backpressure/NoOpBackpressureMonitor : io/sentry/backpressure/IBackpressureMonitor {
+	public fun getDownsampleFactor ()I
+	public static fun getInstance ()Lio/sentry/backpressure/NoOpBackpressureMonitor;
+	public fun start ()V
+}
+
 public class io/sentry/cache/EnvelopeCache : io/sentry/cache/IEnvelopeCache {
 	public static final field CRASH_MARKER_FILE Ljava/lang/String;
 	public static final field NATIVE_CRASH_MARKER_FILE Ljava/lang/String;
@@ -4429,6 +4458,7 @@ public final class io/sentry/transport/AsyncHttpTransport : io/sentry/transport/
 	public fun close ()V
 	public fun flush (J)V
 	public fun getRateLimiter ()Lio/sentry/transport/RateLimiter;
+	public fun isHealthy ()Z
 	public fun send (Lio/sentry/SentryEnvelope;Lio/sentry/Hint;)V
 }
 
@@ -4444,6 +4474,7 @@ public abstract interface class io/sentry/transport/ICurrentDateProvider {
 public abstract interface class io/sentry/transport/ITransport : java/io/Closeable {
 	public abstract fun flush (J)V
 	public abstract fun getRateLimiter ()Lio/sentry/transport/RateLimiter;
+	public fun isHealthy ()Z
 	public fun send (Lio/sentry/SentryEnvelope;)V
 	public abstract fun send (Lio/sentry/SentryEnvelope;Lio/sentry/Hint;)V
 }
@@ -4478,6 +4509,7 @@ public final class io/sentry/transport/RateLimiter {
 	public fun <init> (Lio/sentry/transport/ICurrentDateProvider;Lio/sentry/SentryOptions;)V
 	public fun filter (Lio/sentry/SentryEnvelope;Lio/sentry/Hint;)Lio/sentry/SentryEnvelope;
 	public fun isActiveForCategory (Lio/sentry/DataCategory;)Z
+	public fun isAnyRateLimitActive ()Z
 	public fun updateRetryAfterLimits (Ljava/lang/String;Ljava/lang/String;I)V
 }
 

sentry/src/main/java/io/sentry/Hub.java

@@ -604,6 +604,11 @@ public void bindClient(final @NotNull ISentryClient client) {
     }
   }
 
+  @Override
+  public boolean isHealthy() {
+    return stack.peek().getClient().isHealthy();
+  }
+
   @Override
   public void flush(long timeoutMillis) {
     if (!isEnabled()) {

sentry/src/main/java/io/sentry/HubAdapter.java

@@ -168,6 +168,11 @@ public void bindClient(@NotNull ISentryClient client) {
     Sentry.bindClient(client);
   }
 
+  @Override
+  public boolean isHealthy() {
+    return Sentry.isHealthy();
+  }
+
   @Override
   public void flush(long timeoutMillis) {
     Sentry.flush(timeoutMillis);

sentry/src/main/java/io/sentry/IHub.java

@@ -329,6 +329,13 @@ default void addBreadcrumb(@NotNull String message, @NotNull String category) {
    */
   void bindClient(@NotNull ISentryClient client);
 
+  /**
+   * Whether the transport is healthy.
+   *
+   * @return true if the transport is healthy
+   */
+  boolean isHealthy();
+
   /**
    * Flushes events queued up, but keeps the Hub enabled. Not implemented yet.
    *

sentry/src/main/java/io/sentry/ISentryClient.java

@@ -273,4 +273,9 @@ SentryId captureTransaction(
   @ApiStatus.Internal
   @Nullable
   RateLimiter getRateLimiter();
+
+  @ApiStatus.Internal
+  default boolean isHealthy() {
+    return true;
+  }
 }

sentry/src/main/java/io/sentry/NoOpHub.java

@@ -131,6 +131,11 @@ public void configureScope(@NotNull ScopeCallback callback) {}
   @Override
   public void bindClient(@NotNull ISentryClient client) {}
 
+  @Override
+  public boolean isHealthy() {
+    return false;
+  }
+
   @Override
   public void flush(long timeoutMillis) {}
 

sentry/src/main/java/io/sentry/Sentry.java

@@ -1,5 +1,6 @@
 package io.sentry;
 
+import io.sentry.backpressure.BackpressureMonitor;
 import io.sentry.cache.EnvelopeCache;
 import io.sentry.cache.IEnvelopeCache;
 import io.sentry.config.PropertiesProviderFactory;
@@ -391,6 +392,11 @@ private static boolean initConfigurations(final @NotNull SentryOptions options)
       options.addCollector(new JavaMemoryCollector());
     }
 
+    if (options.isEnableBackpressureHandling()) {
+      options.setBackpressureMonitor(new BackpressureMonitor(options, HubAdapter.getInstance()));
+      options.getBackpressureMonitor().start();
+    }
+
     return true;
   }
 
@@ -731,6 +737,10 @@ public static void bindClient(final @NotNull ISentryClient client) {
     getCurrentHub().bindClient(client);
   }
 
+  public static boolean isHealthy() {
+    return getCurrentHub().isHealthy();
+  }
+
   /**
    * Flushes events queued up to the current hub. Not implemented yet.
    *

sentry/src/main/java/io/sentry/SentryClient.java

@@ -941,6 +941,11 @@ public void flush(final long timeoutMillis) {
     return transport.getRateLimiter();
   }
 
+  @Override
+  public boolean isHealthy() {
+    return transport.isHealthy();
+  }
+
   private boolean sample() {
     // https://docs.sentry.io/development/sdk-dev/features/#event-sampling
     if (options.getSampleRate() != null && random != null) {