Implement NSSecureCoding for GDLLogStorage (#2216)

* Implement NSSecureCoding for GDLLogStorage

* Fix style

* Rename variable

Author: mikehaney24

GoogleDataLogger/GoogleDataLogger/Classes/GDLLogStorage.m

@@ -180,17 +180,35 @@ - (void)addLogToTrackingCollections:(GDLLogEvent *)log logFile:(NSURL *)logFile
 
 #pragma mark - NSSecureCoding
 
+/** The NSKeyedCoder key for the logHashToFile property. */
+static NSString *const kGDLLogHashToLogFileKey = @"logHashToLogFileKey";
+
+/** The NSKeyedCoder key for the logTargetToLogFileSet property. */
+static NSString *const kGDLLogTargetToLogSetKey = @"logTargetToLogFileSetKey";
+
 + (BOOL)supportsSecureCoding {
   return YES;
 }
 
 - (instancetype)initWithCoder:(NSCoder *)aDecoder {
-  // TODO
-  return [self.class sharedInstance];
+  // Create the singleton and populate its ivars.
+  GDLLogStorage *sharedInstance = [self.class sharedInstance];
+  dispatch_sync(sharedInstance.storageQueue, ^{
+    Class NSMutableDictionaryClass = [NSMutableDictionary class];
+    sharedInstance->_logHashToLogFile =
+        [aDecoder decodeObjectOfClass:NSMutableDictionaryClass forKey:kGDLLogHashToLogFileKey];
+    sharedInstance->_logTargetToLogFileSet =
+        [aDecoder decodeObjectOfClass:NSMutableDictionaryClass forKey:kGDLLogTargetToLogSetKey];
+  });
+  return sharedInstance;
 }
 
 - (void)encodeWithCoder:(NSCoder *)aCoder {
-  // TODO
+  GDLLogStorage *sharedInstance = [self.class sharedInstance];
+  dispatch_sync(sharedInstance.storageQueue, ^{
+    [aCoder encodeObject:sharedInstance->_logHashToLogFile forKey:kGDLLogHashToLogFileKey];
+    [aCoder encodeObject:sharedInstance->_logTargetToLogFileSet forKey:kGDLLogTargetToLogSetKey];
+  });
 }
 
 @end

GoogleDataLogger/Tests/GDLLogStorageTest.m

@@ -116,7 +116,23 @@ - (void)testLogEventDeallocationIsEnforced {
 
 /** Tests encoding and decoding the storage singleton correctly. */
 - (void)testNSSecureCoding {
-  // TODO
+  GDLLogEvent *logEvent = [[GDLLogEvent alloc] initWithLogMapID:@"404" logTarget:logTarget];
+  logEvent.extensionBytes = [@"testString" dataUsingEncoding:NSUTF8StringEncoding];
+  NSUInteger logHash = logEvent.hash;
+  XCTAssertNoThrow([[GDLLogStorage sharedInstance] storeLog:logEvent]);
+  logEvent = nil;
+  NSData *storageData = [NSKeyedArchiver archivedDataWithRootObject:[GDLLogStorage sharedInstance]];
+  dispatch_sync([GDLLogStorage sharedInstance].storageQueue, ^{
+    XCTAssertNotNil([GDLLogStorage sharedInstance].logHashToLogFile[@(logHash)]);
+  });
+  [[GDLLogStorage sharedInstance] removeLog:@(logHash) logTarget:@(logTarget)];
+  dispatch_sync([GDLLogStorage sharedInstance].storageQueue, ^{
+    XCTAssertNil([GDLLogStorage sharedInstance].logHashToLogFile[@(logHash)]);
+  });
+
+  // TODO(mikehaney24): Ensure that the object created by alloc is discarded?
+  [NSKeyedUnarchiver unarchiveObjectWithData:storageData];
+  XCTAssertNotNil([GDLLogStorage sharedInstance].logHashToLogFile[@(logHash)]);
 }
 
 /** Tests logging a fast log causes an upload attempt. */