ios - 使用 NSURLSession 发送 POST 请求

Question

更新:找到解决方案。可以在文末阅读。

我正在尝试使用 NSURLSession 对远程 REST API 执行 POST 请求。这个想法是使用两个参数发出请求:deviceId 和 textContent。

问题是服务器无法识别这些参数。服务器部分工作正常，因为我已经使用 POSTMAN for Google Chrome 发送了一个 POST 并且它工作得很好。

这是我现在使用的代码:

NSString *deviceID = [[NSUserDefaults standardUserDefaults] objectForKey:@"deviceID"];
NSString *textContent = @"New note";
NSString *noteDataString = [NSString stringWithFormat:@"deviceId=%@&textContent=%@", deviceID, textContent];

NSURLSessionConfiguration *sessionConfiguration = [NSURLSessionConfiguration defaultSessionConfiguration];
sessionConfiguration.HTTPAdditionalHeaders = @{
                                               @"api-key"       : @"API_KEY",
                                               @"Content-Type"  : @"application/json"
                                               };
NSURLSession *session = [NSURLSession sessionWithConfiguration:sessionConfiguration];
NSURL *url = [NSURL URLWithString:@"http://url_to_manage_post_requests"];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
request.HTTPBody = [noteDataString dataUsingEncoding:NSUTF8StringEncoding];
request.HTTPMethod = @"POST";
NSURLSessionDataTask *postDataTask = [session dataTaskWithRequest:request completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
    // The server answers with an error because it doesn't receive the params
}];
[postDataTask resume];

我用 NSURLSessionUploadTask 尝试了相同的过程:

// ...
NSURL *url = [NSURL URLWithString:@"http://url_to_manage_post_requests"];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
request.HTTPMethod = @"POST";
NSURLSessionUploadTask *uploadTask = [session uploadTaskWithRequest:request fromData:[noteDataString dataUsingEncoding:NSUTF8StringEncoding] completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
    // The server answers with an error because it doesn't receive the params
}];
[uploadTask resume];

有什么想法吗？

解决方案

我的方法的问题是我在所有请求中都发送了不正确的 Content-Type header 。因此，代码正常工作所需的唯一更改是删除 Content-Type = application/json HTTP header 。所以正确的代码是这样的:

NSString *deviceID = [[NSUserDefaults standardUserDefaults] objectForKey:@"deviceID"];
NSString *textContent = @"New note";
NSString *noteDataString = [NSString stringWithFormat:@"deviceId=%@&textContent=%@", deviceID, textContent];

NSURLSessionConfiguration *sessionConfiguration = [NSURLSessionConfiguration defaultSessionConfiguration];
sessionConfiguration.HTTPAdditionalHeaders = @{
                                               @"api-key"       : @"API_KEY"
                                               };
NSURLSession *session = [NSURLSession sessionWithConfiguration:sessionConfiguration];
NSURL *url = [NSURL URLWithString:@"http://url_to_manage_post_requests"];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
request.HTTPBody = [noteDataString dataUsingEncoding:NSUTF8StringEncoding];
request.HTTPMethod = @"POST";
NSURLSessionDataTask *postDataTask = [session dataTaskWithRequest:request completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
    // The server answers with an error because it doesn't receive the params
}];
[postDataTask resume];

与其他参数一起发送图像

如果您需要使用 NSURLSession 发布图像以及其他参数，这里有一个示例:

NSString *deviceID = [[NSUserDefaults standardUserDefaults] objectForKey:@"deviceID"];
NSString *textContent = @"This is a new note";

// Build the request body
NSString *boundary = @"SportuondoFormBoundary";
NSMutableData *body = [NSMutableData data];
// Body part for "deviceId" parameter. This is a string.
[body appendData:[[NSString stringWithFormat:@"--%@\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]];
[body appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"%@\"\r\n\r\n", @"deviceId"] dataUsingEncoding:NSUTF8StringEncoding]];
[body appendData:[[NSString stringWithFormat:@"%@\r\n", deviceID] dataUsingEncoding:NSUTF8StringEncoding]];
// Body part for "textContent" parameter. This is a string.
[body appendData:[[NSString stringWithFormat:@"--%@\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]];
[body appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"%@\"\r\n\r\n", @"textContent"] dataUsingEncoding:NSUTF8StringEncoding]];
[body appendData:[[NSString stringWithFormat:@"%@\r\n", textContent] dataUsingEncoding:NSUTF8StringEncoding]];
// Body part for the attachament. This is an image.
NSData *imageData = UIImageJPEGRepresentation([UIImage imageNamed:@"ranking"], 0.6);
if (imageData) {
    [body appendData:[[NSString stringWithFormat:@"--%@\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]];
    [body appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"%@\"; filename=\"image.jpg\"\r\n", @"image"] dataUsingEncoding:NSUTF8StringEncoding]];
    [body appendData:[@"Content-Type: image/jpeg\r\n\r\n" dataUsingEncoding:NSUTF8StringEncoding]];
    [body appendData:imageData];
    [body appendData:[[NSString stringWithFormat:@"\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
}
[body appendData:[[NSString stringWithFormat:@"--%@--\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]];

// Setup the session
NSURLSessionConfiguration *sessionConfiguration = [NSURLSessionConfiguration defaultSessionConfiguration];
sessionConfiguration.HTTPAdditionalHeaders = @{
                                               @"api-key"       : @"55e76dc4bbae25b066cb",
                                               @"Accept"        : @"application/json",
                                               @"Content-Type"  : [NSString stringWithFormat:@"multipart/form-data; boundary=%@", boundary]
                                               };

// Create the session
// We can use the delegate to track upload progress
NSURLSession *session = [NSURLSession sessionWithConfiguration:sessionConfiguration delegate:self delegateQueue:nil];

// Data uploading task. We could use NSURLSessionUploadTask instead of NSURLSessionDataTask if we needed to support uploads in the background
NSURL *url = [NSURL URLWithString:@"URL_TO_UPLOAD_TO"];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
request.HTTPMethod = @"POST";
request.HTTPBody = body;
NSURLSessionDataTask *uploadTask = [session dataTaskWithRequest:request completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
    // Process the response
}];
[uploadTask resume];

Answer 1

您可以尝试使用 NSDictionary 作为参数。以下将正确地将参数发送到 JSON 服务器。

NSError *error;

NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration];
NSURLSession *session = [NSURLSession sessionWithConfiguration:configuration delegate:self delegateQueue:nil];
NSURL *url = [NSURL URLWithString:@"[JSON SERVER"];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url
                                                       cachePolicy:NSURLRequestUseProtocolCachePolicy
                                                   timeoutInterval:60.0];

[request addValue:@"application/json" forHTTPHeaderField:@"Content-Type"];
[request addValue:@"application/json" forHTTPHeaderField:@"Accept"];

[request setHTTPMethod:@"POST"];
NSDictionary *mapData = [[NSDictionary alloc] initWithObjectsAndKeys: @"TEST IOS", @"name",
                     @"IOS TYPE", @"typemap",
                     nil];
NSData *postData = [NSJSONSerialization dataWithJSONObject:mapData options:0 error:&error];
[request setHTTPBody:postData];


NSURLSessionDataTask *postDataTask = [session dataTaskWithRequest:request completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {

}];

[postDataTask resume];

希望这会有所帮助(我正在尝试使用上述方法对 CSRF 真实性问题进行排序 - 但它确实会在 NSDictionary 中发送参数)。