fix: Always start SDK on the main thread

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 ### Fixes
 
+- Start SDK only in the main thread (#3291)
 - Remove "duplicate library" warning (#3312)
 
 ## 8.13.0

Sentry.xcodeproj/project.pbxproj

@@ -776,6 +776,7 @@
 		D86F419827C8FEFA00490520 /* SentryCoreDataTrackerExtension.swift in Sources */ = {isa = PBXBuildFile; fileRef = D86F419727C8FEFA00490520 /* SentryCoreDataTrackerExtension.swift */; };
 		D8751FA5274743710032F4DE /* SentryNSURLSessionTaskSearchTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = D8751FA4274743710032F4DE /* SentryNSURLSessionTaskSearchTests.swift */; };
 		D875ED0B276CC84700422FAC /* SentryNSDataTrackerTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = D875ED0A276CC84700422FAC /* SentryNSDataTrackerTests.swift */; };
+		D87FA2892AB9EB06007DE933 /* MainThreadTestIntegration.swift in Sources */ = {isa = PBXBuildFile; fileRef = D87FA2882AB9EB06007DE933 /* MainThreadTestIntegration.swift */; };
 		D880E3A728573E87008A90DB /* SentryBaggageTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = D880E3A628573E87008A90DB /* SentryBaggageTests.swift */; };
 		D884A20527C80F6300074664 /* SentryCoreDataTrackerTest.swift in Sources */ = {isa = PBXBuildFile; fileRef = D884A20327C80F2700074664 /* SentryCoreDataTrackerTest.swift */; };
 		D885266427739D01001269FC /* SentryFileIOTrackingIntegrationTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = D885266327739D01001269FC /* SentryFileIOTrackingIntegrationTests.swift */; };
@@ -1728,6 +1729,7 @@
 		D8751FA4274743710032F4DE /* SentryNSURLSessionTaskSearchTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SentryNSURLSessionTaskSearchTests.swift; sourceTree = "<group>"; };
 		D8757D142A209F7300BFEFCC /* SentrySampleDecision+Private.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = "SentrySampleDecision+Private.h"; path = "include/SentrySampleDecision+Private.h"; sourceTree = "<group>"; };
 		D875ED0A276CC84700422FAC /* SentryNSDataTrackerTests.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = SentryNSDataTrackerTests.swift; sourceTree = "<group>"; };
+		D87FA2882AB9EB06007DE933 /* MainThreadTestIntegration.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MainThreadTestIntegration.swift; sourceTree = "<group>"; };
 		D880E3A628573E87008A90DB /* SentryBaggageTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SentryBaggageTests.swift; sourceTree = "<group>"; };
 		D880E3B02860A5A0008A90DB /* SentryEvent+Private.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = "SentryEvent+Private.h"; path = "include/SentryEvent+Private.h"; sourceTree = "<group>"; };
 		D884A20327C80F2700074664 /* SentryCoreDataTrackerTest.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SentryCoreDataTrackerTest.swift; sourceTree = "<group>"; };
@@ -3182,6 +3184,7 @@
 				84281C4D2A579A0C00EE88F2 /* SentryProfilerMocksSwiftCompatible.mm */,
 				84AC61DA29F7654A009EEF61 /* TestDispatchSourceWrapper.swift */,
 				84A5D75A29D5170700388BFA /* TimeInterval+Sentry.swift */,
+				D87FA2882AB9EB06007DE933 /* MainThreadTestIntegration.swift */,
 				7B30B68126527C55006B2752 /* TestDisplayLinkWrapper.swift */,
 				8E25C97425F8511A00DC215B /* TestRandom.swift */,
 				7BE3C7762445E50A00A38442 /* TestCurrentDateProvider.swift */,
@@ -4484,6 +4487,7 @@
 				84B7FA4529B2926900AD93B1 /* TestDisplayLinkWrapper.swift in Sources */,
 				84AC61DB29F7654A009EEF61 /* TestDispatchSourceWrapper.swift in Sources */,
 				8431F01729B2851500D8DC56 /* TestSentrySystemWrapper.swift in Sources */,
+				D87FA2892AB9EB06007DE933 /* MainThreadTestIntegration.swift in Sources */,
 				84281C632A579D0700EE88F2 /* SentryProfilerMocks.mm in Sources */,
 				84B7FA4129B28CD200AD93B1 /* TestSentryDispatchQueueWrapper.swift in Sources */,
 				84B7FA3E29B28ADD00AD93B1 /* TestClient.swift in Sources */,

SentryTestUtils/MainThreadTestIntegration.swift

@@ -0,0 +1,16 @@
+import Foundation
+import Sentry
+
+public class MainThreadTestIntegration: NSObject, SentryIntegrationProtocol {
+
+    public var installedInTheMainThread = false
+
+    public func install(with options: Options) -> Bool {
+        installedInTheMainThread = Thread.isMainThread
+        return true
+    }
+
+    public static func replaceOptionIntegrations(_ options: Options) {
+        options.integrations = [ NSStringFromClass(MainThreadTestIntegration.self) ]
+    }
+}

Sources/Sentry/SentryReachability.m

@@ -98,6 +98,13 @@
     }
 }
 
+void
+SentryConnectivityReset(void)
+{
+    [sentry_reachability_change_blocks removeAllObjects];
+    sentry_current_reachability_state = kSCNetworkReachabilityFlagsUninitialized;
+}
+
 @implementation SentryReachability
 
 + (void)initialize

Sources/Sentry/SentrySDK.m

@@ -8,12 +8,14 @@
 #import "SentryCrash.h"
 #import "SentryCrashWrapper.h"
 #import "SentryDependencyContainer.h"
+#import "SentryDispatchQueueWrapper.h"
 #import "SentryFileManager.h"
 #import "SentryHub+Private.h"
 #import "SentryLog.h"
 #import "SentryMeta.h"
 #import "SentryOptions+Private.h"
 #import "SentryScope.h"
+#import "SentryThreadWrapper.h"
 #import "SentryUIDeviceWrapper.h"
 
 @interface
@@ -135,27 +137,29 @@ + (void)setStartInvocations:(NSUInteger)value
 
 + (void)startWithOptions:(SentryOptions *)options
 {
-    startInvocations++;
+    [SentryThreadWrapper onMainThread:^{
+        startInvocations++;
 
-    [SentryLog configure:options.debug diagnosticLevel:options.diagnosticLevel];
+        [SentryLog configure:options.debug diagnosticLevel:options.diagnosticLevel];
 
-    SentryClient *newClient = [[SentryClient alloc] initWithOptions:options];
-    [newClient.fileManager moveAppStateToPreviousAppState];
-    [newClient.fileManager moveBreadcrumbsToPreviousBreadcrumbs];
+        SentryClient *newClient = [[SentryClient alloc] initWithOptions:options];
+        [newClient.fileManager moveAppStateToPreviousAppState];
+        [newClient.fileManager moveBreadcrumbsToPreviousBreadcrumbs];
 
-    SentryScope *scope
-        = options.initialScope([[SentryScope alloc] initWithMaxBreadcrumbs:options.maxBreadcrumbs]);
-    // The Hub needs to be initialized with a client so that closing a session
-    // can happen.
-    [SentrySDK setCurrentHub:[[SentryHub alloc] initWithClient:newClient andScope:scope]];
-    SENTRY_LOG_DEBUG(@"SDK initialized! Version: %@", SentryMeta.versionString);
-    [SentrySDK installIntegrations];
+        SentryScope *scope = options.initialScope(
+            [[SentryScope alloc] initWithMaxBreadcrumbs:options.maxBreadcrumbs]);
+        // The Hub needs to be initialized with a client so that closing a session
+        // can happen.
+        [SentrySDK setCurrentHub:[[SentryHub alloc] initWithClient:newClient andScope:scope]];
+        SENTRY_LOG_DEBUG(@"SDK initialized! Version: %@", SentryMeta.versionString);
+        [SentrySDK installIntegrations];
 
-    [SentryCrashWrapper.sharedInstance startBinaryImageCache];
-    [SentryDependencyContainer.sharedInstance.binaryImageCache start];
+        [SentryCrashWrapper.sharedInstance startBinaryImageCache];
+        [SentryDependencyContainer.sharedInstance.binaryImageCache start];
 #if TARGET_OS_IOS
-    [SentryDependencyContainer.sharedInstance.uiDeviceWrapper start];
+        [SentryDependencyContainer.sharedInstance.uiDeviceWrapper start];
 #endif
+    }];
 }
 
 + (void)startWithConfigureOptions:(void (^)(SentryOptions *options))configureOptions

Tests/SentryTests/Networking/SentryReachabilityTests.m

@@ -2,6 +2,8 @@
 #import "SentryReachability.h"
 #import <XCTest/XCTest.h>
 
+void SentryConnectivityReset(void);
+
 @interface TestSentryReachabilityObserver : NSObject <SentryReachabilityObserver>
 @end
 @implementation TestSentryReachabilityObserver
@@ -22,6 +24,7 @@ - (void)setUp
 - (void)tearDown
 {
     self.reachability = nil;
+    SentryConnectivityReset();
 }
 
 - (void)testConnectivityRepresentations

Tests/SentryTests/SentrySDKTests.swift

@@ -653,7 +653,21 @@ class SentrySDKTests: XCTestCase {
 
         XCTAssertEqual(flushTimeout, transport.flushInvocations.first)
     }
-
+
+//    func testStartInTheMainThread() {
+//        let expect = expectation(description: "SDK Initialization")
+//        DispatchQueue.global(qos: .background).async {
+//            SentrySDK.start { options in
+//                MainThreadTestIntegration.replaceOptionIntegrations(options)
+//            }
+//            expect.fulfill()
+//        }
+//        wait(for: [expect], timeout: 0.5)
+//
+//        let mainThreadIntegration = SentrySDK.currentHub().installedIntegrations().first { integration in integration is MainThreadTestIntegration } as? MainThreadTestIntegration
+//        XCTAssertEqual(mainThreadIntegration?.installedInTheMainThread, true, "SDK is not being initialized in the main thread")
+//    }
+
 #if SENTRY_HAS_UIKIT
 
     func testSetAppStartMeasurementConcurrently() {