[Perf] Add networkInstrumentationEnabled opt-out flag (#8277)

FirebasePerformance/CHANGELOG.md

@@ -1,6 +1,11 @@
 # Unreleased
 - [fixed] Fixed a race condition crash in `FPRConfigurations` by making
   `remoteConfigFlags` atomic and explicitly nullable. (#16144)
+- [added] Added a `networkInstrumentationEnabled` opt-out for URLSession and
+  URLConnection swizzling. Settable via `Info.plist` key
+  `firebase_performance_network_instrumentation_enabled` or at runtime via
+  `Performance.sharedInstance().isNetworkInstrumentationEnabled`. Defaults to
+  true. (#8277)
 
 # 12.13.0
 - [fixed] Fixed NSURLSession delegate instrumentation for NSProxy delegates. (#14478)

FirebasePerformance/Sources/Configurations/FPRConfigurations.h

@@ -51,6 +51,13 @@ FOUNDATION_EXTERN FPRConfigName kFPRConfigDataCollectionEnabled;
 /** The config KVC name string for the instrumentationEnabled property. */
 FOUNDATION_EXTERN FPRConfigName kFPRConfigInstrumentationEnabled;
 
+/** Enables or disables the URLSession/URLConnection network instrumentation only. Other
+ * instrumentation (app start, screen rendering, custom traces) is unaffected. Default is YES. */
+@property(nonatomic, getter=isNetworkInstrumentationEnabled) BOOL networkInstrumentationEnabled;
+
+/** The config KVC name string for the networkInstrumentationEnabled property. */
+FOUNDATION_EXTERN FPRConfigName kFPRConfigNetworkInstrumentationEnabled;
+
 /** Log source against which the Fireperf events are recorded. */
 @property(nonatomic, readonly) int logSource;
 

FirebasePerformance/Sources/Configurations/FPRConfigurations.m

@@ -29,10 +29,17 @@
 
 FPRConfigName kFPRConfigInstrumentationEnabled = @"instrumentationEnabled";
 
+FPRConfigName kFPRConfigNetworkInstrumentationEnabled = @"networkInstrumentationEnabled";
+
 NSString *const kFPRConfigInstrumentationUserPreference =
     @"com.firebase.performanceInsrumentationEnabled";
 NSString *const kFPRConfigInstrumentationPlistKey = @"firebase_performance_instrumentation_enabled";
 
+NSString *const kFPRConfigNetworkInstrumentationUserPreference =
+    @"com.firebase.performanceNetworkInstrumentationEnabled";
+NSString *const kFPRConfigNetworkInstrumentationPlistKey =
+    @"firebase_performance_network_instrumentation_enabled";
+
 NSString *const kFPRConfigCollectionUserPreference = @"com.firebase.performanceCollectionEnabled";
 NSString *const kFPRConfigCollectionPlistKey = @"firebase_performance_collection_enabled";
 
@@ -62,6 +69,8 @@ + (void)reset {
   gSharedInstanceToken = 0;
   [[GULUserDefaults standardUserDefaults]
       removeObjectForKey:kFPRConfigInstrumentationUserPreference];
+  [[GULUserDefaults standardUserDefaults]
+      removeObjectForKey:kFPRConfigNetworkInstrumentationUserPreference];
   [[GULUserDefaults standardUserDefaults] removeObjectForKey:kFPRConfigCollectionUserPreference];
 }
 
@@ -217,6 +226,31 @@ - (BOOL)isInstrumentationEnabled {
   return instrumentationPreference;
 }
 
+- (void)setNetworkInstrumentationEnabled:(BOOL)networkInstrumentationEnabled {
+  [self.userDefaults setBool:networkInstrumentationEnabled
+                      forKey:kFPRConfigNetworkInstrumentationUserPreference];
+}
+
+- (BOOL)isNetworkInstrumentationEnabled {
+  // Resolves in order: GULUserDefaults, Info.plist, defaults to YES.
+  BOOL networkInstrumentationPreference = YES;
+
+  id networkInstrumentationPreferenceObject =
+      [self.userDefaults objectForKey:kFPRConfigNetworkInstrumentationUserPreference];
+
+  if (networkInstrumentationPreferenceObject) {
+    networkInstrumentationPreference = [networkInstrumentationPreferenceObject boolValue];
+  } else {
+    networkInstrumentationPreferenceObject =
+        [self objectForInfoDictionaryKey:kFPRConfigNetworkInstrumentationPlistKey];
+    if (networkInstrumentationPreferenceObject) {
+      networkInstrumentationPreference = [networkInstrumentationPreferenceObject boolValue];
+    }
+  }
+
+  return networkInstrumentationPreference;
+}
+
 #pragma mark - Fireperf SDK configurations.
 
 - (BOOL)sdkEnabled {

FirebasePerformance/Sources/FIRPerformance.m

@@ -106,6 +106,20 @@ - (void)setInstrumentationEnabled:(BOOL)instrumentationEnabled {
   }
 }
 
+- (BOOL)isNetworkInstrumentationEnabled {
+  return [FPRConfigurations sharedInstance].isNetworkInstrumentationEnabled;
+}
+
+- (void)setNetworkInstrumentationEnabled:(BOOL)networkInstrumentationEnabled {
+  [[FPRConfigurations sharedInstance]
+      setNetworkInstrumentationEnabled:networkInstrumentationEnabled];
+  if (self.fprClient.isSwizzled) {
+    FPRLogError(kFPRInstrumentationDisabledAfterConfigure,
+                @"Network instrumentation preference will only take effect on next app start "
+                @"because Firebase Performance has already been configured.");
+  }
+}
+
 #pragma mark - Custom attributes related methods
 
 - (NSDictionary<NSString *, NSString *> *)attributes {

FirebasePerformance/Sources/FPRClient.m

@@ -172,7 +172,9 @@ - (BOOL)startWithConfiguration:(FPRConfiguration *)config error:(NSError *__auto
 - (void)checkAndStartInstrumentation {
   BOOL instrumentationEnabled = self.configuration.isInstrumentationEnabled;
   if (instrumentationEnabled && !self.isSwizzled) {
-    [self.instrumentation registerInstrumentGroup:kFPRInstrumentationGroupNetworkKey];
+    if (self.configuration.isNetworkInstrumentationEnabled) {
+      [self.instrumentation registerInstrumentGroup:kFPRInstrumentationGroupNetworkKey];
+    }
     [self.instrumentation registerInstrumentGroup:kFPRInstrumentationGroupUIKitKey];
     self.swizzled = YES;
   }

FirebasePerformance/Sources/Public/FirebasePerformance/FIRPerformance.h

@@ -51,6 +51,18 @@ NS_SWIFT_NAME(Performance)
  */
 @property(nonatomic, assign, getter=isInstrumentationEnabled) BOOL instrumentationEnabled;
 
+/**
+ * Controls only the automatic URLSession/URLConnection network instrumentation. Other
+ * instrumentation (app start, screen rendering, custom traces) is unaffected. Setting this value
+ * to false has immediate effect only if done before calling FirebaseApp.configure(). Otherwise it
+ * takes effect on the next app start. Default is true.
+ *
+ * This setting is persisted, and is applied on future invocations of your application. Once
+ * explicitly set, it overrides any settings in your `Info.plist`.
+ */
+@property(nonatomic, assign, getter=isNetworkInstrumentationEnabled)
+    BOOL networkInstrumentationEnabled;
+
 /** @return The shared instance. */
 + (nonnull instancetype)sharedInstance NS_SWIFT_NAME(sharedInstance());