If you haven’t thought about using AFNetworking, you should. It makes dealing with web-services much easier. I have done something similar to what I think you are wanting to do. I wrote a custom class to fire off network requests. Here ya go:
NetworkClient.h
/*
NetworkClient.h
Created by LJ Wilson on 2/3/12.
Copyright (c) 2012 LJ Wilson. All rights reserved.
License:
Permission is hereby granted, free of charge, to any person obtaining a copy of this software
and associated documentation files (the "Software"), to deal in the Software without restriction,
including without limitation the rights to use, copy, modify, merge, publish, distribute,
sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or
substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT
OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#import <Foundation/Foundation.h>
extern NSString * const APIKey;
@interface NetworkClient : NSObject
+(void)processURLRequestWithURL:(NSString *)url
andParams:(NSDictionary *)params
block:(void (^)(id obj))block;
+(void)processURLRequestWithURL:(NSString *)url
andParams:(NSDictionary *)params
syncRequest:(BOOL)syncRequest
block:(void (^)(id obj))block;
+(void)processURLRequestWithURL:(NSString *)url
andParams:(NSDictionary *)params
syncRequest:(BOOL)syncRequest
alertUserOnFailure:(BOOL)alertUserOnFailure
block:(void (^)(id obj))block;
+(void)processFileUploadRequestWithURL:(NSString *)url
andParams:(NSDictionary *)params
fileData:(NSData *)fileData
fileName:(NSString *)fileName
mimeType:(NSString *)mimeType
block:(void (^)(id obj))block;
+(void)handleNetworkErrorWithError:(NSError *)error;
+(void)handleNoAccessWithReason:(NSString *)reason;
@end
NetworkClient.m
/*
NetworkClient.m
Created by LJ Wilson on 2/3/12.
Copyright (c) 2012 LJ Wilson. All rights reserved.
License:
Permission is hereby granted, free of charge, to any person obtaining a copy of this software
and associated documentation files (the "Software"), to deal in the Software without restriction,
including without limitation the rights to use, copy, modify, merge, publish, distribute,
sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or
substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT
OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#import "NetworkClient.h"
#import "AFHTTPClient.h"
#import "AFHTTPRequestOperation.h"
#import "SBJson.h"
NSString * const APIKey = @"APIKEY GOES HERE IF YOU WANT TO USE ONE";
@implementation NetworkClient
+(void)processURLRequestWithURL:(NSString *)url
andParams:(NSDictionary *)params
block:(void (^)(id obj))block {
[self processURLRequestWithURL:url andParams:params syncRequest:NO alertUserOnFailure:NO block:^(id obj) {
block(obj);
}];
}
+(void)processURLRequestWithURL:(NSString *)url
andParams:(NSDictionary *)params
syncRequest:(BOOL)syncRequest
block:(void (^)(id obj))block {
[self processURLRequestWithURL:url andParams:params syncRequest:syncRequest alertUserOnFailure:NO block:^(id obj) {
block(obj);
}];
}
+(void)processURLRequestWithURL:(NSString *)url
andParams:(NSDictionary *)params
syncRequest:(BOOL)syncRequest
alertUserOnFailure:(BOOL)alertUserOnFailure
block:(void (^)(id obj))block {
// Default url goes here, pass in a nil to use it
if (url == nil) {
url = @"http://www.mydomain.com/mywebservice";
}
NSMutableDictionary *dict = [[NSMutableDictionary alloc] initWithDictionary:params];
[dict setValue:APIKey forKey:@"APIKey"];
NSDictionary *newParams = [[NSDictionary alloc] initWithDictionary:dict];
NSURL *requestURL;
AFHTTPClient *httpClient = [[AFHTTPClient alloc] initWithBaseURL:requestURL];
NSMutableURLRequest *theRequest = [httpClient requestWithMethod:@"POST" path:url parameters:newParams];
__block NSString *responseString = [NSString stringWithString:@""];
AFHTTPRequestOperation *_operation = [[AFHTTPRequestOperation alloc] initWithRequest:theRequest];
__weak AFHTTPRequestOperation *operation = _operation;
[operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
responseString = [operation responseString];
id retObj = [responseString JSONValue];
// Check for invalid response (No Access)
if ([retObj isKindOfClass:[NSDictionary class]]) {
if ([[(NSDictionary *)retObj valueForKey:@"Message"] isEqualToString:@"No Access"]) {
block(nil);
[self handleNoAccessWithReason:[(NSDictionary *)retObj valueForKey:@"Reason"]];
}
} else if ([retObj isKindOfClass:[NSArray class]]) {
if ([(NSArray *)retObj count] > 0) {
NSDictionary *dict = [(NSArray *)retObj objectAtIndex:0];
if ([[dict valueForKey:@"Message"] isEqualToString:@"No Access"]) {
block(nil);
[self handleNoAccessWithReason:[(NSDictionary *)retObj valueForKey:@"Reason"]];
}
}
}
block(retObj);
}
failure:^(AFHTTPRequestOperation *operation, NSError *error) {
NSLog(@"Failed with error = %@", [NSString stringWithFormat:@"[Error]:%@",error]);
block(nil);
if (alertUserOnFailure) {
// Let the user know something went wrong
[self handleNetworkErrorWithError:operation.error];
}
}];
[operation start];
if (syncRequest) {
// Process the request syncronously
[operation waitUntilFinished];
}
}
#pragma mark - processFileUpload
+(void)processFileUploadRequestWithURL:(NSString *)url
andParams:(NSDictionary *)params
fileData:(NSData *)fileData
fileName:(NSString *)fileName
mimeType:(NSString *)mimeType
block:(void (^)(id obj))block {
// Default url goes here, pass in a nil to use it
if (url == nil) {
url = @"http://www.mydomain.com/mywebservice";
}
NSMutableDictionary *dict = [[NSMutableDictionary alloc] initWithDictionary:params];
[dict setValue:APIKey forKey:@"APIKey"];
NSDictionary *newParams = [[NSDictionary alloc] initWithDictionary:dict];
AFHTTPClient *client= [AFHTTPClient clientWithBaseURL:[NSURL URLWithString:url]];
NSMutableURLRequest *myRequest = [client multipartFormRequestWithMethod:@"POST"
path:@""
parameters:newParams
constructingBodyWithBlock: ^(id <AFMultipartFormData>formData) {
[formData appendPartWithFileData:fileData name:fileName fileName:fileName mimeType:mimeType];
}];
AFHTTPRequestOperation *_operation = [[AFHTTPRequestOperation alloc] initWithRequest:myRequest];
__weak AFHTTPRequestOperation *operation = _operation;
__block NSString *responseString = [NSString stringWithString:@""];
[operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
responseString = [operation responseString];
id retObj = [responseString JSONValue];
// Check for invalid response (No Access)
if ([retObj isKindOfClass:[NSDictionary class]]) {
if ([[(NSDictionary *)retObj valueForKey:@"Message"] isEqualToString:@"No Access"]) {
block(nil);
[self handleNoAccessWithReason:[(NSDictionary *)retObj valueForKey:@"Reason"]];
}
} else if ([retObj isKindOfClass:[NSArray class]]) {
if ([(NSArray *)retObj count] > 0) {
NSDictionary *dict = [(NSArray *)retObj objectAtIndex:0];
if ([[dict valueForKey:@"Message"] isEqualToString:@"No Access"]) {
block(nil);
[self handleNoAccessWithReason:[(NSDictionary *)retObj valueForKey:@"Reason"]];
}
}
}
block(retObj);
}
failure:^(AFHTTPRequestOperation *operation, NSError *error) {
NSLog(@"Failed with error = %@", [NSString stringWithFormat:@"[Error]:%@",error]);
block(nil);
// if (alertUserOnFailure) {
// // Let the user know something went wrong
// [self handleNetworkErrorWithError:operation.error];
// }
}];
[operation start];
}
#pragma mark - Error and Access Handling
+(void)handleNetworkErrorWithError:(NSError *)error {
NSString *errorString = [NSString stringWithFormat:@"[Error]:%@",error];
// Standard UIAlert Syntax
UIAlertView *myAlert = [[UIAlertView alloc]
initWithTitle:@"Connection Error"
message:errorString
delegate:nil
cancelButtonTitle:@"OK"
otherButtonTitles:nil, nil];
[myAlert show];
}
+(void)handleNoAccessWithReason:(NSString *)reason {
// Standard UIAlert Syntax
UIAlertView *myAlert = [[UIAlertView alloc]
initWithTitle:@"No Access"
message:reason
delegate:nil
cancelButtonTitle:@"OK"
otherButtonTitles:nil, nil];
[myAlert show];
}
@end
Some of this is specific to what I do. All my web services use an APIKey to enhance security and they all do security checks before processing any requests. The network client will return either an NSDictionary or an NSArray depending on what the web service returns (in JSON).
To use the image upload, you would call this in your VC like this (use as many parameters as you need.:
NSData *imageData = UIImagePNGRepresentation(myImage);
NSString *fileName = @"MyFileName.png";
NSDictionary *params = [NSDictionary dictionaryWithObjectsAndKeys:
@"Param1", @"Param1Name",
@"Param2", @"Param2Name",
@"Param3", @"Param3Name",
nil];
// Uses default URL
[NetworkClient processFileUploadRequestWithURL:nil
andParams:params
fileData:imageData
fileName:fileName
mimeType:@"image/png"
block:^(id obj) {
if ([obj isKindOfClass:[NSArray class]]) {
// Successful upload, do other processing as needed
}
}];
Feel free to strip out what you don’t need. Just leave the copyright notice in place.