Merge pull request #272 from Microsoft/feature/init-services-by-priority

Feature/init services by priority

MobileCenter/MobileCenter/Internals/MSMobileCenterInternal.h

@@ -12,8 +12,6 @@
 static NSString *const kMSInstallIdKey = @"MSInstallId";
 static NSString *const kMSMobileCenterIsEnabledKey = @"MSMobileCenterIsEnabled";
 
-@class MSService;
-
 @interface MSMobileCenter ()
 
 @property(nonatomic) id<MSLogManager> logManager;
@@ -57,4 +55,12 @@ static NSString *const kMSMobileCenterIsEnabledKey = @"MSMobileCenterIsEnabled";
  */
 + (NSString *)logTag;
 
-@end
+
+/**
+ * Sort the array of services in descending order based on their priority.
+ *
+ * @return The array of services in descending order.
+ */
+- (NSArray *)sortServices:(NSArray<Class> *)services;
+
+  @end

MobileCenter/MobileCenter/Internals/MSServiceCommon.h

@@ -8,7 +8,7 @@
 NS_ASSUME_NONNULL_BEGIN
 
 /**
- * Protocol declaring services common logic.
+ * Protocol declaring public common logic for services.
  */
 @protocol MSServiceCommon <NSObject>
 
@@ -52,6 +52,11 @@ NS_ASSUME_NONNULL_BEGIN
  */
 @property(nonatomic, readonly) MSPriority priority;
 
+/**
+ * The initialization priority for this service.
+ */
+@property(nonatomic, readonly) MSInitializationPriority initializationPriority;
+
 /**
  * Get the unique instance.
  *

MobileCenter/MobileCenter/Internals/MSServiceInternal.h

@@ -8,6 +8,9 @@
 
 /**
  *  Protocol declaring all the logic of a service. This is what concrete services needs to conform to.
+ *  The difference is that MSServiceCommon is public, while MSServiceInternal is private.
+ *  Some properties are present in both, which is counter-intuitive but the way we implemented this
+ *  to achieve abstraction and not have empty implementations in MSServiceAbstract.
  */
 @protocol MSServiceInternal <MSService, MSServiceCommon>
 
@@ -19,10 +22,15 @@
 @property(nonatomic, copy, readonly) NSString *storageKey;
 
 /**
- * The channel priority for this service.
+ * The channel priority for this service. Defined here as well as in MSServiceCommon to achieve abstraction.
  */
 @property(nonatomic, readonly) MSPriority priority;
 
+/**
+ * The initialization priority for this service. Defined here as well as in MSServiceCommon to achieve abstraction.
+ */
+@property(nonatomic, readonly) MSInitializationPriority initializationPriority;
+
 /**
  * The app secret for the SDK.
  */
@@ -31,7 +39,7 @@
 /**
  * Get the unique instance.
  *
- * @return unique instance.
+ * @return The unique instance.
  */
 + (instancetype)sharedInstance;
 

MobileCenter/MobileCenter/Internals/Utils/MSConstants+Internal.h

@@ -17,10 +17,22 @@ static NSString *const kMSContentType = @"application/json";
 static NSString *const kMSAPIVersion = @"1.0.0-preview20160914";
 static NSString *const kMSAPIVersionKey = @"api_version";
 
-// Channel priorities, check the kMSPriorityCount if you add a new value.
-typedef NS_ENUM(NSInteger, MSPriority) { MSPriorityDefault, MSPriorityBackground, MSPriorityHigh };
+/** Channel priorities, check the kMSPriorityCount if you add a new value.
+ * The order matters here! Values NEED to range from low priority to high priority.
+ */
+typedef NS_ENUM(NSInteger, MSPriority) { MSPriorityBackground, MSPriorityDefault, MSPriorityHigh };
 static short const kMSPriorityCount = MSPriorityHigh + 1;
 
+/**
+ * The priority by which the modules are initialized.
+ *  MSPriorityMax is reserved for only 1 module and this needs to be Crashes. Crashes needs to be initialized first to
+ *  catch crashes in our other SDK Modules (which will hopefully never happen) and to avoid losing any log at crash time.
+ */
+typedef NS_ENUM(NSInteger, MSInitializationPriority) { MSInitializationPriorityDefault = 500, MSInitializationPriorityMax = 999 };
+
+/**
+ * Enum with the different HTTP status codes.
+ */
 typedef NS_ENUM(NSInteger, MSHTTPCodesNo) {
   // Informational
   MSHTTPCodesNo1XXInformationalUnknown = 1,

MobileCenter/MobileCenter/MSMobileCenter.m

@@ -176,12 +176,35 @@ static NSString *const kMSDefaultBaseUrl = @"https://in.mobile.azure.com";
 - (void)start:(NSString *)appSecret withServices:(NSArray<Class> *)services {
   BOOL configured = [self configure:appSecret];
   if (configured) {
-    for (Class service in services) {
+
+    NSArray *sortedServices = [self sortServices:services];
+
+    for (Class service in sortedServices) {
       [self startService:service];
     }
   }
 }
 
+- (NSArray *)sortServices:(NSArray<Class> *)services {
+  // Sort services in descending order to make sure the service with the highest priority gets initialized first.
+  // This is intended to make sure Crashes gets initialized first.
+  if (services && services.count > 1) {
+    return [services sortedArrayUsingComparator:^NSComparisonResult(Class clazzA, Class clazzB) {
+        id <MSServiceInternal> serviceA = [clazzA sharedInstance];
+        id <MSServiceInternal> serviceB = [clazzB sharedInstance];
+
+        if (serviceA.initializationPriority < serviceB.initializationPriority) {
+          return NSOrderedDescending;
+        }
+        else {
+          return NSOrderedAscending;
+        }
+    }];
+  } else {
+    return services;
+  }
+}
+
 - (void)startService:(Class)clazz {
   id<MSServiceInternal> service = [clazz sharedInstance];
 

MobileCenter/MobileCenterTests/MSMobileCenterTest.m

@@ -2,8 +2,10 @@
 #import "MSMobileCenter.h"
 #import "MSMobileCenterInternal.h"
 #import "MSMobileCenterPrivate.h"
+#import "OCMock.h"
 #import <OCHamcrestIOS/OCHamcrestIOS.h>
 #import <XCTest/XCTest.h>
+#import "MSServiceInternal.h"
 
 static NSString *const kSMInstallIdStringExample = @"F18499DA-5C3D-4F05-B4E8-D8C9C06A6F09";
 
@@ -139,4 +141,24 @@ static NSString *const kSMNullifiedInstallIdString = @"00000000-0000-0000-0000-0
   [MSMobileCenter configureWithAppSecret:@"App-Secret"];
   XCTAssertTrue([MSMobileCenter isConfigured]);
 }
+
+- (void)testSortingServicesWorks {
+  
+  // If
+  id<MSServiceCommon> mockServiceMaxPrio = OCMProtocolMock(@protocol(MSServiceCommon));
+  OCMStub([mockServiceMaxPrio sharedInstance]).andReturn(mockServiceMaxPrio);
+  OCMStub([mockServiceMaxPrio initializationPriority]).andReturn(MSInitializationPriorityMax);
+
+  id<MSServiceCommon> mockServiceDefaultPrio = OCMProtocolMock(@protocol(MSServiceCommon));
+  OCMStub([mockServiceDefaultPrio sharedInstance]).andReturn(mockServiceDefaultPrio);
+  OCMStub([mockServiceDefaultPrio initializationPriority]).andReturn(MSInitializationPriorityDefault);
+  
+  // When
+  NSArray<MSServiceAbstract *> *sorted = [self.sut sortServices:@[mockServiceDefaultPrio, mockServiceMaxPrio]];
+
+  // Then
+  XCTAssertTrue([sorted[0] initializationPriority] == MSInitializationPriorityMax);
+  XCTAssertTrue([sorted[1] initializationPriority] == MSInitializationPriorityDefault);
+}
+
 @end

MobileCenter/MobileCenterTests/MSServiceAbstractTest.m

@@ -37,6 +37,10 @@
   return MSPriorityDefault;
 }
 
+- (MSInitializationPriority)initializationPriority {
+  return MSInitializationPriorityDefault;
+}
+
 + (NSString *)logTag {
   return @"MSServiceAbstractTest";
 }
@@ -319,4 +323,8 @@
   OCMVerify([logManagerMock setEnabled:YES andDeleteDataOnDisabled:YES forPriority:self.abstractService.priority]);
 }
 
+- (void)testInitializationPriorityCorrect {
+  XCTAssertTrue([self.abstractService initializationPriority] == MSInitializationPriorityDefault);
+}
+
 @end

MobileCenterAnalytics/MobileCenterAnalytics/MSAnalytics.m

@@ -71,6 +71,10 @@ static dispatch_once_t onceToken;
   return MSPriorityDefault;
 }
 
+- (MSInitializationPriority)initializationPriority {
+  return MSInitializationPriorityDefault;
+}
+
 #pragma mark - MSServiceAbstract
 
 - (void)applyEnabledState:(BOOL)isEnabled {

MobileCenterAnalytics/MobileCenterAnalyticsTests/MSAnalyticsTests.m

@@ -268,4 +268,8 @@ static NSString *const kMSTestAppSecret = @"TestAppSecret";
   self.didFailSendingEventLogWasCalled = true;
 }
 
+- (void)testInitializationPriorityCorrect {
+  XCTAssertTrue([[MSAnalytics sharedInstance] initializationPriority] == MSInitializationPriorityDefault);
+}
+
 @end

MobileCenterCrashes/MobileCenterCrashes/MSCrashes.mm

@@ -272,6 +272,10 @@ static void uncaught_cxx_exception_handler(const MSCrashesUncaughtCXXExceptionIn
   return MSPriorityHigh;
 }
 
+- (MSInitializationPriority)initializationPriority {
+  return MSInitializationPriorityMax;
+}
+
 #pragma mark - MSLogManagerDelegate
 
 /**
@@ -506,17 +510,18 @@ static void uncaught_cxx_exception_handler(const MSCrashesUncaughtCXXExceptionIn
     if ([[tmp pathExtension] isEqualToString:kMSLogBufferFileExtension]) {
       NSString *filePath = [self.logBufferDir stringByAppendingPathComponent:tmp];
       NSData *serializedLog = [NSData dataWithContentsOfFile:filePath];
-
-      id <MSLog> item = [NSKeyedUnarchiver unarchiveObjectWithData:serializedLog];
-      if (item) {
-        if ([((NSObject *) item) isKindOfClass:[MSAppleErrorLog class]]) {
-          [self.logManager processLog:item withPriority:self.priority];
-        } else {
-          [self.logManager processLog:item withPriority:MSPriorityDefault];
+      if(serializedLog && serializedLog.length && serializedLog.length > 0) {
+        id <MSLog> item = [NSKeyedUnarchiver unarchiveObjectWithData:serializedLog];
+        if (item) {
+          if ([((NSObject *) item) isKindOfClass:[MSAppleErrorLog class]]) {
+            [self.logManager processLog:item withPriority:self.priority];
+          } else {
+            [self.logManager processLog:item withPriority:MSPriorityDefault];
+          }
         }
+        // Create empty new file, overwrites the old one.
+        [[NSFileManager defaultManager] createFileAtPath:filePath contents:[NSData data] attributes:nil];
       }
-      // Create empty new file, overwrites the old one.
-      [[NSFileManager defaultManager] createFileAtPath:filePath contents:[NSData data] attributes:nil];
     }
   }
 }

MobileCenterCrashes/MobileCenterCrashesTests/MSCrashesTests.mm

@@ -222,4 +222,8 @@ static NSString *const kMSTestAppSecret = @"TestAppSecret";
   XCTAssertTrue(self.sut.bufferIndex == 1);
 }
 
+- (void)testInitializationPriorityCorrect {
+  XCTAssertTrue([[MSCrashes sharedInstance] initializationPriority] == MSInitializationPriorityMax);
+}
+
 @end