Revert GDTCORStorage changes for now (#5778)

* Revert "Refactor event saving and searching (#5773)"

This reverts commit a61786c.

* Revert "Expand the storage protocol and provide an event iterator (#5742)"

This reverts commit 641d853.

* Revert "Implement helpers for storing and finding events (#5738)"

This reverts commit 9a0aed8.

Author: mikehaney24

GoogleDataTransport/GDTCORLibrary/GDTCORFlatFileStorage.m

@@ -20,21 +20,12 @@
 #import <GoogleDataTransport/GDTCORConsoleLogger.h>
 #import <GoogleDataTransport/GDTCOREvent.h>
 #import <GoogleDataTransport/GDTCORLifecycle.h>
-#import <GoogleDataTransport/GDTCORPlatform.h>
 #import <GoogleDataTransport/GDTCORPrioritizer.h>
-#import <GoogleDataTransport/GDTCORStorageEventSelector.h>
 
 #import "GDTCORLibrary/Private/GDTCOREvent_Private.h"
-#import "GDTCORLibrary/Private/GDTCORFlatFileStorageIterator.h"
 #import "GDTCORLibrary/Private/GDTCORRegistrar_Private.h"
 #import "GDTCORLibrary/Private/GDTCORUploadCoordinator.h"
 
-NSString *const gGDTCORFlatFileStorageEventDataPathKey = @"DataPath";
-
-NSString *const gGDTCORFlatFileStorageMappingIDPathKey = @"MappingIDPath";
-
-NSString *const gGDTCORFlatFileStorageQoSTierPathKey = @"QoSTierPath";
-
 @implementation GDTCORFlatFileStorage
 
 + (void)load {
@@ -60,115 +51,27 @@ + (NSString *)archivePath {
   return archivePath;
 }
 
-+ (NSString *)baseEventStoragePath {
-  static NSString *eventDataPath;
++ (NSString *)libraryDataPath {
+  static NSString *libraryDataPath;
   static dispatch_once_t onceToken;
   dispatch_once(&onceToken, ^{
-    eventDataPath =
+    libraryDataPath =
         [GDTCORRootDirectory() URLByAppendingPathComponent:NSStringFromClass([self class])
                                                isDirectory:YES]
             .path;
-    eventDataPath = [eventDataPath stringByAppendingPathComponent:@"gdt_event_data"];
-    if (![[NSFileManager defaultManager] fileExistsAtPath:eventDataPath isDirectory:NULL]) {
+    libraryDataPath = [libraryDataPath stringByAppendingPathComponent:@"gdt_library_data"];
+    if (![[NSFileManager defaultManager] fileExistsAtPath:libraryDataPath isDirectory:NULL]) {
       NSError *error;
-      [[NSFileManager defaultManager] createDirectoryAtPath:eventDataPath
+      [[NSFileManager defaultManager] createDirectoryAtPath:libraryDataPath
                                 withIntermediateDirectories:YES
                                                  attributes:0
                                                       error:&error];
       GDTCORAssert(error == nil, @"Creating the library data path failed: %@", error);
     }
   });
-  return eventDataPath;
-}
-
-+ (NSString *)libraryDataStoragePath {
-  static NSString *libraryDataPath;
-  static dispatch_once_t onceToken;
-  dispatch_once(&onceToken, ^{
-    libraryDataPath =
-        [GDTCORRootDirectory() URLByAppendingPathComponent:NSStringFromClass([self class])
-                                               isDirectory:YES]
-            .path;
-    libraryDataPath = [libraryDataPath stringByAppendingPathComponent:@"gdt_library_data"];
-  });
-  if (![[NSFileManager defaultManager] fileExistsAtPath:libraryDataPath isDirectory:NULL]) {
-    NSError *error;
-    [[NSFileManager defaultManager] createDirectoryAtPath:libraryDataPath
-                              withIntermediateDirectories:YES
-                                               attributes:0
-                                                    error:&error];
-    GDTCORAssert(error == nil, @"Creating the library data path failed: %@", error);
-  }
   return libraryDataPath;
 }
 
-+ (NSString *)pathForTarget:(GDTCORTarget)target
-                    eventID:(NSNumber *)eventID
-                    qosTier:(NSNumber *)qosTier
-                  mappingID:(NSString *)mappingID {
-  return
-      [NSString stringWithFormat:@"%@/%ld/%@.%@.%@", [GDTCORFlatFileStorage baseEventStoragePath],
-                                 (long)target, eventID, qosTier, mappingID];
-}
-
-+ (NSSet<NSString *> *)pathsForTarget:(GDTCORTarget)target
-                             eventIDs:(nullable NSSet<NSNumber *> *)eventIDs
-                             qosTiers:(nullable NSSet<NSNumber *> *)qosTiers
-                           mappingIDs:(nullable NSSet<NSString *> *)mappingIDs {
-  NSMutableSet<NSString *> *paths = [[NSMutableSet alloc] init];
-  NSFileManager *fileManager = [NSFileManager defaultManager];
-  NSString *targetPath = [NSString
-      stringWithFormat:@"%@/%ld", [GDTCORFlatFileStorage baseEventStoragePath], (long)target];
-  NSError *error;
-  NSArray<NSString *> *dirPaths = [fileManager contentsOfDirectoryAtPath:targetPath error:&error];
-  if (error) {
-    GDTCORLogDebug(@"There was an error reading the contents of the target path: %@", error);
-    return paths;
-  }
-  BOOL checkingIDs = eventIDs.count > 0;
-  BOOL checkingQosTiers = qosTiers.count > 0;
-  BOOL checkingMappingIDs = mappingIDs.count > 0;
-  BOOL checkingAnything = checkingIDs == NO && checkingQosTiers == NO && checkingMappingIDs == NO;
-  for (NSString *path in dirPaths) {
-    if (checkingAnything) {
-      [paths addObject:path];
-      continue;
-    }
-    NSString *filename = [path lastPathComponent];
-    NSArray<NSString *> *components = [filename componentsSeparatedByString:@"."];
-    if (components.count != 3) {
-      GDTCORLogDebug(@"There was an error reading the filename components: %@", components);
-      [[NSFileManager defaultManager] removeItemAtPath:path error:nil];
-      continue;
-    }
-    NSNumber *eventID = @(components[0].integerValue);
-    NSNumber *qosTier = @(components[1].integerValue);
-    NSString *mappingID = components[2];
-    if (eventID == nil || qosTier == nil) {
-      GDTCORLogDebug(@"There was an error parsing the filename components: %@", components);
-      [[NSFileManager defaultManager] removeItemAtPath:path error:nil];
-      continue;
-    }
-    NSNumber *eventIDMatch = checkingIDs ? @([eventIDs containsObject:eventID]) : nil;
-    NSNumber *qosTierMatch = checkingQosTiers ? @([qosTiers containsObject:qosTier]) : nil;
-    NSNumber *mappingIDMatch = checkingMappingIDs ? @([mappingIDs containsObject:mappingID]) : nil;
-    if ((eventIDMatch == nil || eventIDMatch.boolValue) &&
-        (qosTierMatch == nil || qosTierMatch.boolValue) &&
-        (mappingIDMatch == nil || mappingIDMatch.boolValue)) {
-      [paths addObject:path];
-    }
-  }
-  return paths;
-}
-
-+ (NSArray<NSString *> *)searchPathsWithEventSelector:(GDTCORStorageEventSelector *)eventSelector {
-  NSSet *searchPaths = [GDTCORFlatFileStorage pathsForTarget:eventSelector.selectedTarget
-                                                    eventIDs:eventSelector.selectedEventIDs
-                                                    qosTiers:eventSelector.selectedQosTiers
-                                                  mappingIDs:eventSelector.selectedMappingIDs];
-  return [searchPaths allObjects];
-}
-
 + (instancetype)sharedInstance {
   static GDTCORFlatFileStorage *sharedStorage;
   static dispatch_once_t onceToken;
@@ -311,7 +214,7 @@ - (void)libraryDataForKey:(nonnull NSString *)key
                onComplete:
                    (nonnull void (^)(NSData *_Nullable, NSError *_Nullable error))onComplete {
   dispatch_async(_storageQueue, ^{
-    NSString *dataPath = [[[self class] libraryDataStoragePath] stringByAppendingPathComponent:key];
+    NSString *dataPath = [[[self class] libraryDataPath] stringByAppendingPathComponent:key];
     NSError *error;
     NSData *data = [NSData dataWithContentsOfFile:dataPath options:0 error:&error];
     if (onComplete) {
@@ -322,7 +225,7 @@ - (void)libraryDataForKey:(nonnull NSString *)key
 
 - (void)storeLibraryData:(NSData *)data
                   forKey:(nonnull NSString *)key
-              onComplete:(nullable void (^)(NSError *_Nullable error))onComplete {
+              onComplete:(nonnull void (^)(NSError *_Nullable error))onComplete {
   if (!data || data.length <= 0) {
     if (onComplete) {
       onComplete([NSError errorWithDomain:NSInternalInconsistencyException code:-1 userInfo:nil]);
@@ -331,7 +234,7 @@ - (void)storeLibraryData:(NSData *)data
   }
   dispatch_async(_storageQueue, ^{
     NSError *error;
-    NSString *dataPath = [[[self class] libraryDataStoragePath] stringByAppendingPathComponent:key];
+    NSString *dataPath = [[[self class] libraryDataPath] stringByAppendingPathComponent:key];
     [data writeToFile:dataPath options:NSDataWritingAtomic error:&error];
     if (onComplete) {
       onComplete(error);
@@ -343,7 +246,7 @@ - (void)removeLibraryDataForKey:(nonnull NSString *)key
                      onComplete:(nonnull void (^)(NSError *_Nullable error))onComplete {
   dispatch_async(_storageQueue, ^{
     NSError *error;
-    NSString *dataPath = [[[self class] libraryDataStoragePath] stringByAppendingPathComponent:key];
+    NSString *dataPath = [[[self class] libraryDataPath] stringByAppendingPathComponent:key];
     if ([[NSFileManager defaultManager] fileExistsAtPath:dataPath]) {
       [[NSFileManager defaultManager] removeItemAtPath:dataPath error:&error];
       if (onComplete) {
@@ -353,61 +256,6 @@ - (void)removeLibraryDataForKey:(nonnull NSString *)key
   });
 }
 
-- (BOOL)hasEventsForTarget:(GDTCORTarget)target {
-  // TODO(mikehaney24): Increase the performance of this call.
-  GDTCORStorageEventSelector *eventSelector =
-      [[GDTCORStorageEventSelector alloc] initWithTarget:target
-                                                eventIDs:nil
-                                              mappingIDs:nil
-                                                qosTiers:nil];
-  id<GDTCORStorageEventIterator> iter = [self iteratorWithSelector:eventSelector];
-  return [iter nextEvent] != nil;
-}
-
-- (nullable id<GDTCORStorageEventIterator>)iteratorWithSelector:
-    (nonnull GDTCORStorageEventSelector *)eventSelector {
-  __block GDTCORFlatFileStorageIterator *iterator;
-  dispatch_sync(_storageQueue, ^{
-    NSArray<NSString *> *searchPaths =
-        [GDTCORFlatFileStorage searchPathsWithEventSelector:eventSelector];
-    iterator.eventFiles = searchPaths;
-  });
-  return iterator;
-}
-
-- (void)purgeEventsFromBefore:(GDTCORClock *)beforeSnapshot
-                   onComplete:(void (^)(NSError *_Nullable error))onComplete {
-  // TODO(mikehaney24): Figure out how we're going to deal with this.
-}
-
-- (void)storageSizeWithCallback:(void (^)(uint64_t storageSize))onComplete {
-  dispatch_async(_storageQueue, ^{
-    unsigned long long totalBytes = 0;
-    NSString *eventDataPath = [GDTCORFlatFileStorage baseEventStoragePath];
-    NSString *libraryDataPath = [GDTCORFlatFileStorage libraryDataStoragePath];
-    NSDirectoryEnumerator *enumerator =
-        [[NSFileManager defaultManager] enumeratorAtPath:eventDataPath];
-    while ([enumerator nextObject]) {
-      NSFileAttributeType fileType = enumerator.fileAttributes[NSFileType];
-      if ([fileType isEqual:NSFileTypeRegular]) {
-        NSNumber *fileSize = enumerator.fileAttributes[NSFileSize];
-        totalBytes += fileSize.unsignedLongLongValue;
-      }
-    }
-    enumerator = [[NSFileManager defaultManager] enumeratorAtPath:libraryDataPath];
-    while ([enumerator nextObject]) {
-      NSFileAttributeType fileType = enumerator.fileAttributes[NSFileType];
-      if ([fileType isEqual:NSFileTypeRegular]) {
-        NSNumber *fileSize = enumerator.fileAttributes[NSFileSize];
-        totalBytes += fileSize.unsignedLongLongValue;
-      }
-    }
-    if (onComplete) {
-      onComplete(totalBytes);
-    }
-  });
-}
-
 #pragma mark - Private helper methods
 
 /** Saves the event's dataObject to a file using NSData mechanisms.
@@ -462,8 +310,8 @@ - (void)appWillForeground:(GDTCORApplication *)app {
 
 - (void)appWillBackground:(GDTCORApplication *)app {
   dispatch_async(_storageQueue, ^{
-    // Immediately request a background task to run until the end of the current queue of work,
-    // and cancel it once the work is done.
+    // Immediately request a background task to run until the end of the current queue of work, and
+    // cancel it once the work is done.
     __block GDTCORBackgroundIdentifier bgID =
         [app beginBackgroundTaskWithName:@"GDTStorage"
                        expirationHandler:^{