Easier way to send JSON Data with Objective-C to PHP server? - ios

Question

I have a PHP RESTful server that I connect to to invoke methods based on the URL path called from my objective-c program. I use the ASIHTTPRequest and SBJson.
Everything works well but I'm doing requests in different controllers and now duplicated methods are in all those controllers. What is the best way to abstract that code (requests) in a single class, so I can easily re-use the code, so I can keep the controllers more simple.
Please save me from what I feel to be a redundant and repetitive coding sequence.
I have tried to make a singleton class, but each view controller requires different request connect points, and most view controllers require specific actions to be called when the succeeded method is called and Im not sure how to handle it all.
Here is what my code template currently looks like in the Objective-c program:
//*1) Somewhere at the top of my .m file I have this*
//These are the suffixes to the URL path that I connect to at my server,
//depending on the action required
NSString *const RequestCreateCustomer = #"Create/Customer";
NSString *const RequestUpdateCustomer = #"Update/Customer";
NSString *const RequestDeleteCustomer = #"Delete/Customer";
//*2) Then I have my connection invocation code*
//Method invocation, all of them look something like this
-navigationButton{
...
[self retrieveWithRequestStringType:RequestUpdateCustomer];
}
-(void)retrieveWithRequestStringType:(NSString*)typeOfRequest{
NSLog(#"Retrieve %# method called", typeOfRequest);
NSString *urlString = [NSString stringWithFormat:#"%#/Secure/CB/%#", #"http://www.defaultStapleURLToMyServer.com/CB", typeOfRequest];
NSString *encodedUrlString = [urlString stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSURL *url = [[NSURL alloc] initWithString:encodedUrlString];
serverRequest = nil;
serverRequest = [ASIFormDataRequest requestWithURL:url];
[serverRequest addRequestHeader:#"Content-Type" value:#"application/json"];
[serverRequest addRequestHeader:#"Request-Method" value:#"POST"];
//Normally at this point depending on the request type, I prepare some data that needs to be sent along with the request
NSMutableDictionary *completeDataArray = [[NSMutableDictionary alloc] init];
if([typeOfRequest isEqualToString:RequestCreateCustomer]){
[serverRequest setUserInfo:[NSDictionary dictionaryWithObject:RequestCreateCustomer forKey:#"RequestType"]];
if( ! [self validateAndPrepareAllData:&completeDataArray]){
return;
}
}
else if([typeOfRequest isEqualToString:RequestUpdateCustomer]){
[serverRequest setUserInfo:[NSDictionary dictionaryWithObject:RequestUpdateCustomer forKey:#"RequestType"]];
if( ! [self validateAndPrepareAllData:&completeDataArray]){
return;
}
}
else if([typeOfRequest isEqualToString:RequestDeleteCustomer]){
[serverRequest setUserInfo:[NSDictionary dictionaryWithObject:RequestDeleteCustomer forKey:#"RequestType"]];
if( ! [self validateAndPrepareCustomerIdData:&completeDataArray]){
return;
}
}
NSString *jsonString = [completeDataArray JSONRepresentation];
[serverRequest appendPostData:[jsonString dataUsingEncoding:NSUTF8StringEncoding]];
[serverRequest setDelegate:self];
[serverRequest setDidFinishSelector:#selector(requestSucceeded:)];
[serverRequest setDidFailSelector:#selector(requestFailed:)];
[serverRequest startAsynchronous];
}
//*3) And heres the connection did succeed, and connection did fail methods*
-(void)requestSucceeded:(ASIHTTPRequest*)request{
NSInteger statusCode = [[[request responseHeaders] objectForKey:#"StatusCode"] intValue];
NSLog(#"StatusCode: %#", [[request responseHeaders] objectForKey:#"StatusCode"]);
NSString *myString = [[NSString alloc] initWithData:[request responseData] encoding:NSUTF8StringEncoding];
NSDictionary *JSONDictionary = [myString JSONValue];
switch (statusCode) {
case 400:
case 401:
{
NSLog(#"display error message");
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"Error" message:[[request.responseString JSONValue] objectForKey:#"Message"] delegate:nil cancelButtonTitle:#"Ok" otherButtonTitles: nil];
[alert show];
break;
}
case 200:
NSLog(#"status code = 200 so successful");
//Created customer request succeeded
if([[[request userInfo] objectForKey:#"RequestType"] isEqualToString:RequestCreateCustomer]){
[self.delegate addedCustomerVCWithCustomer:[[CustomerDataModel alloc] initWithJSONData:[JSONDictionary objectForKey:#"CustomerObject"]]];
[self cancelModalView];
}
//Edit customer request succeeded
else if([[[request userInfo] objectForKey:#"RequestType"] isEqualToString:RequestUpdateCustomer]){
[self.delegate editedCustomerVCWithCustomer:[[CustomerDataModel alloc] initWithJSONData:[JSONDictionary objectForKey:#"CustomerObject"]]];
[self cancelModalView];
}
//Delete customer request succeeded
else if([[[request userInfo] objectForKey:#"RequestType"] isEqualToString:RequestDeleteCustomer]){
[self.delegate deletedCustomer:customer];
[self cancelModalView];
}
break;
default:
[SVProgressHUD showErrorWithStatus:[NSString stringWithFormat:#"went to none: %d or %#", (int)statusCode, [[request responseHeaders] objectForKey:#"StatusCode"]]];
NSLog(#"went to none: %d or %#", (int)statusCode, [[request responseHeaders] objectForKey:#"StatusCode"]);
break;
}
[SVProgressHUD dismiss];
}
-(void)requestFailed:(ASIHTTPRequest*)request{
if([[[request userInfo] objectForKey:#"RquestType"] isEqualToString:RequestCreateCustomer]){
NSLog(#"retrieving states failed so trying again");
[self addCustomerRequest];
}
else if(){
//... you get the point
}
}
Can someone help out with an alternative solution?

Answer 1

create a new class that has blocks/delegate (but prefers block) on it.. let's say Request.h and Request.m.. and make a public method with a block parameter.. example
this should be public methods
typedef void(^CompletionBlock)(id results);
typedef void(^ErrorBlock)(NSError *error);
- (void)setCompetionBlock:(CompletionBlock)block; and
- (void)setErrorBlock:(ErrorBlock)error;
and make a variable name.. this should be private variables
CompletionBlock completionBlock;
ErrorBlock errorBlock;
and declare this methods in your .m
- (void)setCompletionBlock:(CompletionBlock)aCompletionBlock {
completionBlock = [aCompletionBlock copy];
}
- (void)setErrorBlock:(ErrorBlock)aError {
errorBlock = [aError copy];
}
- (void)reportSuccess:(id)results {
if (completionBlock) {
dispatch_async(dispatch_get_main_queue(), ^{
completionBlock(results);
});
}
}
- (void)reportFailure:(NSError *)error {
if (errorBlock) {
dispatch_async(dispatch_get_main_queue(), ^{
errorBlock(error);
});
}
}
and call [self reportSuccess:jsonSuccess]; under your success methods, in your code it is -(void)requestSucceeded:(ASIHTTPRequest*)request{ and [self reportFailure:NSerror*] under -(void)requestFailed:(ASIHTTPRequest*)request
and to call this class
Request *req = [Request alloc]init];
[req retrieveWithRequestStringType:#"sample"];
[req setCompletion:^(id result){
}];
[req setErrorBlock:(NSError *error) {
}];