feat(ios): implement multipart requests

- expose new AFHTTPSessionManager method "uploadTaskWithHTTPMethod"

src/ios/AFNetworking/AFHTTPSessionManager.h

@@ -290,6 +290,27 @@ NS_ASSUME_NONNULL_BEGIN
                          success:(nullable void (^)(NSURLSessionDataTask *task, id _Nullable responseObject))success
                          failure:(nullable void (^)(NSURLSessionDataTask * _Nullable task, NSError *error))failure;
 
+/**
+ Creates and runs an `NSURLSessionDataTask` with a multipart request using given HTTP method.
+
+ @param HTTPMethod The HTTP method used to create the request.
+ @param URLString The URL string used to create the request URL.
+ @param parameters The parameters to be encoded according to the client request serializer.
+ @param block A block that takes a single argument and appends data to the HTTP body. The block argument is an object adopting the `AFMultipartFormData` protocol.
+ @param uploadProgress A block object to be executed when the upload progress is updated. Note this block is called on the session queue, not the main queue.
+ @param success A block object to be executed when the task finishes successfully. This block has no return value and takes two arguments: the data task, and the response object created by the client response serializer.
+ @param failure A block object to be executed when the task finishes unsuccessfully, or that finishes successfully, but encountered an error while parsing the response data. This block has no return value and takes a two arguments: the data task and the error describing the network or parsing error that occurred.
+
+ @see -dataTaskWithRequest:uploadProgress:downloadProgress:completionHandler:
+ */
+- (nullable NSURLSessionDataTask *)uploadTaskWithHTTPMethod:(NSString *)HTTPMethod
+                              URLString:(NSString *)URLString
+                             parameters:(nullable id)parameters
+              constructingBodyWithBlock:(nullable void (^)(id <AFMultipartFormData> formData))block
+                               progress:(nullable void (^)(NSProgress *uploadProgress))uploadProgress
+                                success:(nullable void (^)(NSURLSessionDataTask *task, id _Nullable responseObject))success
+                                failure:(nullable void (^)(NSURLSessionDataTask * _Nullable task, NSError *error))failure;
+
 @end
 
 NS_ASSUME_NONNULL_END

src/ios/AFNetworking/AFHTTPSessionManager.m

@@ -223,6 +223,42 @@
     return dataTask;
 }
 
+- (NSURLSessionDataTask *)PUT:(NSString *)URLString
+                    parameters:(id)parameters
+     constructingBodyWithBlock:(void (^)(id <AFMultipartFormData> formData))block
+                      progress:(nullable void (^)(NSProgress * _Nonnull))uploadProgress
+                       success:(void (^)(NSURLSessionDataTask *task, id responseObject))success
+                       failure:(void (^)(NSURLSessionDataTask *task, NSError *error))failure
+{
+    NSError *serializationError = nil;
+    NSMutableURLRequest *request = [self.requestSerializer multipartFormRequestWithMethod:@"POST" URLString:[[NSURL URLWithString:URLString relativeToURL:self.baseURL] absoluteString] parameters:parameters constructingBodyWithBlock:block error:&serializationError];
+    if (serializationError) {
+        if (failure) {
+            dispatch_async(self.completionQueue ?: dispatch_get_main_queue(), ^{
+                failure(nil, serializationError);
+            });
+        }
+
+        return nil;
+    }
+
+    __block NSURLSessionDataTask *task = [self uploadTaskWithStreamedRequest:request progress:uploadProgress completionHandler:^(NSURLResponse * __unused response, id responseObject, NSError *error) {
+        if (error) {
+            if (failure) {
+                failure(task, error);
+            }
+        } else {
+            if (success) {
+                success(task, responseObject);
+            }
+        }
+    }];
+
+    [task resume];
+
+    return task;
+}
+
 - (NSURLSessionDataTask *)PATCH:(NSString *)URLString
                      parameters:(id)parameters
                         success:(void (^)(NSURLSessionDataTask *task, id responseObject))success
@@ -247,6 +283,43 @@
     return dataTask;
 }
 
+- (NSURLSessionDataTask *)uploadTaskWithHTTPMethod:(NSString *)method
+                     URLString:(NSString *)URLString
+                    parameters:(id)parameters
+     constructingBodyWithBlock:(void (^)(id <AFMultipartFormData> formData))block
+                      progress:(nullable void (^)(NSProgress * _Nonnull))uploadProgress
+                       success:(void (^)(NSURLSessionDataTask *task, id responseObject))success
+                       failure:(void (^)(NSURLSessionDataTask *task, NSError *error))failure
+{
+    NSError *serializationError = nil;
+    NSMutableURLRequest *request = [self.requestSerializer multipartFormRequestWithMethod:method URLString:[[NSURL URLWithString:URLString relativeToURL:self.baseURL] absoluteString] parameters:parameters constructingBodyWithBlock:block error:&serializationError];
+    if (serializationError) {
+        if (failure) {
+            dispatch_async(self.completionQueue ?: dispatch_get_main_queue(), ^{
+                failure(nil, serializationError);
+            });
+        }
+
+        return nil;
+    }
+
+    __block NSURLSessionDataTask *task = [self uploadTaskWithStreamedRequest:request progress:uploadProgress completionHandler:^(NSURLResponse * __unused response, id responseObject, NSError *error) {
+        if (error) {
+            if (failure) {
+                failure(task, error);
+            }
+        } else {
+            if (success) {
+                success(task, responseObject);
+            }
+        }
+    }];
+
+    [task resume];
+
+    return task;
+}
+
 - (NSURLSessionDataTask *)dataTaskWithHTTPMethod:(NSString *)method
                                        URLString:(NSString *)URLString
                                       parameters:(id)parameters