Disable backup of documents folder and all its sub

问题:

I have an already running enterprise application which stores a lot of documents inside the documents folders. I wish to disable the iCloud backup of all these documents and folders inside the Documents folder. The problem is that the contents inside the folder keep on changing dynamically and the idea of adding kCFURLIsExcludedFromBackupKey for every files sounds a bit difficult, as there are multiple classes in my code which can write to the documents directory.

Is there any way I can disable the upload of the entire documents folder and its subfolder.

回答1:

Perhaps the files are changing dynamically because they are being regularly updated from a server or similar? If so, then the answer is to move your file storage from the <Application_Home>/Documents directory to the <Application_Home>/Library/Caches directory. These documents will not be backed up. This is of course only suitable if the data can be re-downloaded or recreated in the future, if required.

See this Apple documentation for an overview: https://developer.apple.com/icloud/documentation/data-storage/index.html

回答2:

In appDelegate of your application in the following method

 - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions

Add this code

    NSArray *urlArray = [[NSFileManager defaultManager] URLsForDirectory: NSDocumentDirectory inDomains: NSUserDomainMask];
    NSURL *documentsUrl = [urlArray firstObject];

    NSError *error = nil;
    BOOL success = [documentsUrl setResourceValue: [NSNumber numberWithBool: YES]
                                  forKey: NSURLIsExcludedFromBackupKey error: &error];
    if(!success){
        NSLog(@"Error in disabling %@ from backup %@", [documentsUrl lastPathComponent], error);
    }

回答3:

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *directory = paths[0];
NSFileManager *fileManager = [NSFileManager defaultManager];
NSURL *url = [NSURL fileURLWithPath:directory];

NSError *error;
// exclude from iCloud backup
if ([url setResourceValue:@(YES) forKey:NSURLIsExcludedFromBackupKey error:&error] == NO) {
        NSLog(@"Error: Unable to exclude directory from backup: %@", error);
}

You can call these once at first install. And it will apply on subfolders and files.

回答4:

You can put kCFURLIsExcludedFromBackupKey (or NSURLIsExcludedFromBackupKey) to the entire Documents directory just like you would for a single file. However, if you don't want any of the files backed up, you may want to rethink where they should go. The Documents directory is for user data only. If files are stored on your own servers, they should probably go in Caches because they can be downloaded again easily. If the files are only needed for a short period of time, they should go in tmp/.

This is Apple's documentation about where to put your app's files.