How to download a file and save it to the documents directory with AFNetworking?

NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:@"..."]];AFHTTPRequestOperation *operation = [[[AFHTTPRequestOperation alloc] initWithRequest:request] autorelease];NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);NSString *path = [[paths objectAtIndex:0] stringByAppendingPathComponent:@"filename"];operation.outputStream = [NSOutputStream outputStreamToFileAtPath:path append:NO];[operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {    NSLog(@"Successfully downloaded file to %@", path);} failure:^(AFHTTPRequestOperation *operation, NSError *error) {    NSLog(@"Error: %@", error);}];[operation start];

I'm gonna bounce off @mattt's answer and post a version for AFNetworking 2.0 using AFHTTPRequestOperationManager.

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);NSString *path = [[paths objectAtIndex:0] stringByAppendingPathComponent:@"filename"];AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];AFHTTPRequestOperation *op = [manager GET:@"http://example.com/file/to/download"                                parameters:nil    success:^(AFHTTPRequestOperation *operation, id responseObject) {         NSLog(@"successful download to %@", path);    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {         NSLog(@"Error: %@", error);    }];op.outputStream = [NSOutputStream outputStreamToFileAtPath:path append:NO];

I'm talking about AFNetworking 2.0

[AFHTTPRequestOperationManager manager] creates manager object with default AFJSONResponseSerializer, and it performs content types restriction. Take a look at this

- (BOOL)validateResponse:(NSHTTPURLResponse *)response                    data:(NSData *)data                   error:(NSError * __autoreleasing *)error

So we need to create a none response serializer and use AFHTTPRequestOperationManager as normal.

Here is the AFNoneResponseSerializer

@interface AFNoneResponseSerializer : AFHTTPResponseSerializer+ (instancetype)serializer;@end@implementation AFNoneResponseSerializer#pragma mark - Initialization+ (instancetype)serializer{    return [[self alloc] init];}- (instancetype)init{    self = [super init];    return self;}#pragma mark - AFURLResponseSerializer- (id)responseObjectForResponse:(NSURLResponse *)response                           data:(NSData *)data                          error:(NSError *__autoreleasing *)error{    return data;}@end

Usage

self.manager = [AFHTTPRequestOperationManager manager];self.manager.responseSerializer = [AFNoneResponseSerializer serializer];[self.manager GET:@"https://sites.google.com/site/iphonesdktutorials/xml/Books.xml"           parameters:parameters              success:^(AFHTTPRequestOperation *operation, id responseObject)    {        if (success) {            success(responseObject);        }    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {        if (failure) {            failure(error);        }    }];

so that we can get the whole file without any serialization