Add scope based feature flags (#4812)

* Add scope based feature flags

* fix equals

* add serialization tests

* Create new reference on buffer clone

* add comment explaining the merge method

* optimize merge method

* make flag and result nullable params

* handle empty/noop buffer on merge and add tests for it

* optimize add method

* format; fix test

* Fix duplicate check

* Update sentry/src/main/java/io/sentry/SentryOptions.java

Co-authored-by: Lorenzo Cian <[email protected]>

* Format code

* changelog

* nullable getFeatureFlags

---------

Co-authored-by: Lorenzo Cian <[email protected]>
Co-authored-by: Sentry Github Bot <[email protected]>

Author: 3 people

CHANGELOG.md

@@ -2,6 +2,14 @@
 
 ## Unreleased
 
+### Features
+
+- Add feature flags API ([#4812](https://github.com/getsentry/sentry-java/pull/4812))
+  - You may now keep track of your feature flag evaluations and have them show up in Sentry.
+  - You may use top level API (`Sentry.addFeatureFlag("my-feature-flag", true);`) or `IScope` and `IScopes` API
+  - Feature flag evaluations tracked on scope(s) will be added to any errors reported to Sentry.
+  - The SDK keeps the latest 100 evaluations from scope(s), replacing old entries as new evaluations are added.
+
 ### Fixes
 
 - Removed SentryExecutorService limit for delayed scheduled tasks ([#4846](https://github.com/getsentry/sentry-java/pull/4846))

sentry-samples/sentry-samples-console-opentelemetry-noagent/src/main/java/io/sentry/samples/console/Main.java

@@ -61,6 +61,8 @@ public static void main(String[] args) throws InterruptedException {
     // Only data added to the scope on `configureScope` above is included.
     Sentry.captureMessage("Some warning!", SentryLevel.WARNING);
 
+    Sentry.addFeatureFlag("my-feature-flag", true);
+
     // Sending exception:
     Exception exception = new RuntimeException("Some error!");
     Sentry.captureException(exception);

sentry-samples/sentry-samples-console-opentelemetry-noagent/src/test/kotlin/sentry/systemtest/ConsoleApplicationSystemTest.kt

@@ -55,7 +55,7 @@ class ConsoleApplicationSystemTest {
     // Verify we received the RuntimeException
     testHelper.ensureErrorReceived { event ->
       event.exceptions?.any { ex -> ex.type == "RuntimeException" && ex.value == "Some error!" } ==
-        true
+        true && testHelper.doesEventHaveFlag(event, "my-feature-flag", true)
     }
 
     // Verify we received the detailed event with fingerprint

sentry-samples/sentry-samples-console/src/main/java/io/sentry/samples/console/Main.java

@@ -126,6 +126,8 @@ public static void main(String[] args) throws InterruptedException {
     // Only data added to the scope on `configureScope` above is included.
     Sentry.captureMessage("Some warning!", SentryLevel.WARNING);
 
+    Sentry.addFeatureFlag("my-feature-flag", true);
+
     // Sending exception:
     Exception exception = new RuntimeException("Some error!");
     Sentry.captureException(exception);

sentry-samples/sentry-samples-console/src/test/kotlin/io/sentry/systemtest/ConsoleApplicationSystemTest.kt

@@ -51,7 +51,7 @@ class ConsoleApplicationSystemTest {
     // Verify we received the RuntimeException
     testHelper.ensureErrorReceived { event ->
       event.exceptions?.any { ex -> ex.type == "RuntimeException" && ex.value == "Some error!" } ==
-        true
+        true && testHelper.doesEventHaveFlag(event, "my-feature-flag", true)
     }
 
     // Verify we received the detailed event with fingerprint

sentry-samples/sentry-samples-jul/src/main/java/io/sentry/samples/jul/Main.java

@@ -1,5 +1,6 @@
 package io.sentry.samples.jul;
 
+import io.sentry.Sentry;
 import java.util.UUID;
 import java.util.logging.Level;
 import java.util.logging.LogManager;
@@ -22,6 +23,10 @@ public static void main(String[] args) throws Exception {
     MDC.put("userId", UUID.randomUUID().toString());
     MDC.put("requestId", UUID.randomUUID().toString());
 
+    Sentry.addFeatureFlag("my-feature-flag", true);
+
+    LOGGER.warning("important warning");
+
     // logging arguments are converted to Sentry Event parameters
     LOGGER.log(Level.INFO, "User has made a purchase of product: %d", 445);
 

sentry-samples/sentry-samples-jul/src/test/kotlin/io/sentry/systemtest/ConsoleApplicationSystemTest.kt

@@ -57,6 +57,11 @@ class ConsoleApplicationSystemTest {
       } != null
     }
 
+    testHelper.ensureErrorReceived { event ->
+      event.message?.message == "important warning" &&
+        testHelper.doesEventHaveFlag(event, "my-feature-flag", true)
+    }
+
     testHelper.ensureLogsReceived { logs, _ ->
       testHelper.doesContainLogWithBody(logs, "User has made a purchase of product: 445") &&
         testHelper.doesContainLogWithBody(logs, "Something went wrong")

sentry-samples/sentry-samples-log4j2/src/main/java/io/sentry/samples/log4j2/Main.java

@@ -1,5 +1,6 @@
 package io.sentry.samples.log4j2;
 
+import io.sentry.Sentry;
 import java.util.UUID;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
@@ -19,6 +20,8 @@ public static void main(String[] args) {
     // ThreadContext tag not listed in log4j2.xml
     ThreadContext.put("context-tag", "context-tag-value");
 
+    Sentry.addFeatureFlag("my-feature-flag", true);
+
     // logging arguments are converted to Sentry Event parameters
     LOGGER.info("User has made a purchase of product: {}", 445);
     // because minimumEventLevel is set to WARN this raises an event

sentry-samples/sentry-samples-log4j2/src/test/kotlin/io/sentry/systemtest/ConsoleApplicationSystemTest.kt

@@ -47,6 +47,11 @@ class ConsoleApplicationSystemTest {
         event.level?.name == "ERROR"
     }
 
+    testHelper.ensureErrorReceived { event ->
+      event.message?.message == "Important warning" &&
+        testHelper.doesEventHaveFlag(event, "my-feature-flag", true)
+    }
+
     testHelper.ensureErrorReceived { event ->
       event.breadcrumbs?.firstOrNull {
         it.message == "Hello Sentry!" && it.level == SentryLevel.DEBUG

sentry-samples/sentry-samples-logback/src/main/java/io/sentry/samples/logback/Main.java

@@ -1,5 +1,6 @@
 package io.sentry.samples.logback;
 
+import io.sentry.Sentry;
 import java.util.UUID;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -17,6 +18,9 @@ public static void main(String[] args) {
     // MDC tag not listed in logback.xml
     MDC.put("context-tag", "context-tag-value");
 
+    Sentry.addFeatureFlag("my-feature-flag", true);
+    LOGGER.warn("important warning");
+
     // logging arguments are converted to Sentry Event parameters
     LOGGER.info("User has made a purchase of product: {}", 445);