AFNetworking 2.0 跟踪文件上传进度

Question

我对 AFNetworking 2.0 比较陌生。使用下面的代码 sn-p，我已经能够成功地将照片上传到我的网址。我想跟踪增量上传进度，但我找不到使用 2.0 版执行此操作的示例。我的应用是 iOS 7，所以我选择了 AFHTTPSessionManager。

谁能提供一个示例，说明如何修改此 sn-p 以跟踪上传进度？

AFHTTPSessionManager *manager = [AFHTTPSessionManager manager];

NSData *imageData = UIImageJPEGRepresentation([UIImage imageNamed:@"myimage.jpg"], 1.0);

[manager POST:@"http://myurl.com" parameters:dataToPost constructingBodyWithBlock:^(id<AFMultipartFormData> formData) {
    [formData appendPartWithFileData:imageData name:@"attachment" fileName:@"myimage.jpg" mimeType:@"image/jpeg"];
} success:^(NSURLSessionDataTask *task, id responseObject) {
    NSLog(@"Success %@", responseObject);
} failure:^(NSURLSessionDataTask *task, NSError *error) {
    NSLog(@"Failure %@, %@", error, [task.response description]);
}];

Answer 1

AFHTTPSession 的接口没有提供设置进度块的方法。相反，您必须执行以下操作：

// 1. Create `AFHTTPRequestSerializer` which will create your request.
AFHTTPRequestSerializer *serializer = [AFHTTPRequestSerializer serializer];

// 2. Create an `NSMutableURLRequest`.
NSMutableURLRequest *request =
    [serializer multipartFormRequestWithMethod:@"POST" URLString:@"http://www.myurl.com"
                                    parameters:dataToPost
                     constructingBodyWithBlock:^(id<AFMultipartFormData> formData) {
                       [formData appendPartWithFileData:imageData
                                                   name:@"attachment"
                                               fileName:@"myimage.jpg"
                                               mimeType:@"image/jpeg"];
                     }];

// 3. Create and use `AFHTTPRequestOperationManager` to create an `AFHTTPRequestOperation` from the `NSMutableURLRequest` that we just created.
AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];
AFHTTPRequestOperation *operation =
    [manager HTTPRequestOperationWithRequest:request
                                     success:^(AFHTTPRequestOperation *operation, id responseObject) {
                                       NSLog(@"Success %@", responseObject);
                                     } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
                                       NSLog(@"Failure %@", error.description);
                                     }];

// 4. Set the progress block of the operation.
[operation setUploadProgressBlock:^(NSUInteger __unused bytesWritten,
                                    long long totalBytesWritten,
                                    long long totalBytesExpectedToWrite) {
  NSLog(@"Wrote %lld/%lld", totalBytesWritten, totalBytesExpectedToWrite);
}];

// 5. Begin!
[operation start];

此外，您不必通过UIImage 读取图像，然后使用JPEG 再次对其进行压缩以获得NSData。只需使用+[NSData dataWithContentsOfFile:] 直接从您的包中读取文件。

Answer 2

AFHTTPSessionManager的接口确实没有提供跟踪上传进度的方法。 但是AFURLSessionManager 可以。

作为AFURLSessionManager 的继承类AFHTTPSessionManager 可以像这样跟踪上传进度：

NSMutableURLRequest *request = [[AFHTTPRequestSerializer serializer]  multipartFormRequestWithMethod:@"POST" URLString:kUploadImageURL parameters:nil constructingBodyWithBlock:^(id<AFMultipartFormData> formData) {
    [formData appendPartWithFileData:UIImageJPEGRepresentation(image, 0.5) name:@"uploadFile" fileName:@"image" mimeType:@"image/jpeg"];
} error:nil];

NSProgress *progress;
NSURLSessionDataTask *uploadTask = [[AFHTTPSessionManager sharedManager] uploadTaskWithStreamedRequest:request progress:&progress completionHandler:^(NSURLResponse *response, id responseObject, NSError *error) {
    if (!error) {
        //handle upload success
    } else {
        //handle upload failure
    }
}];
[uploadTask resume];
[progress addObserver:self forKeyPath:@"fractionCompleted" options:NSKeyValueObservingOptionNew context:NULL];

外面

- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {
    if ([keyPath isEqualToString:@"fractionCompleted"] && [object isKindOfClass:[NSProgress class]]) {
        NSProgress *progress = (NSProgress *)object;
        //progress.fractionCompleted tells you the percent in CGFloat
    }
}

这里是方法2（更新）

使用KVO 跟踪进度意味着self 在观察期间需要活着。更优雅的方式是AFURLSessionManager的方法setTaskDidSendBodyDataBlock，像这样：

AFHTTPSessionManager *manager = [AFHTTPSessionManager manager];
[manager setTaskDidSendBodyDataBlock:^(NSURLSession *session, NSURLSessionTask *task, int64_t bytesSent, int64_t totalBytesSent, int64_t totalBytesExpectedToSend) {
    //during the progress
}];

NSMutableURLRequest *request = [[AFHTTPRequestSerializer serializer]  multipartFormRequestWithMethod:@"POST" URLString:kUploadImageURL parameters:nil constructingBodyWithBlock:^(id<AFMultipartFormData> formData) {
    [formData appendPartWithFileData:UIImageJPEGRepresentation(image, 0.5) name:@"uploadFile" fileName:@"image" mimeType:@"image/jpeg"];
} error:nil];

NSURLSessionDataTask *uploadTask = [manager uploadTaskWithStreamedRequest:request progress:&progress completionHandler:^(NSURLResponse *response, id responseObject, NSError *error) {
    if (!error) {
        //handle upload success
    } else {
        //handle upload failure
    }
}];
[uploadTask resume];