Simple example of NSURLSession with authentication - nsurlsession

I have written a REST service that serves up some data. It is passcode protected.
I am trying to write a background process that will grab the data and stuff it into a sqlLite db I have in the app.
I did this initially without authentication using :
- (void) callWebService {
dispatch_sync(kBgQueue, ^{
NSData* data = [NSData dataWithContentsOfURL:
scoularDirectoryURL];
[self performSelectorOnMainThread:#selector(fetchedData:) withObject:data waitUntilDone:YES];
});
}
This worked fine but I don't think I can add authentication to that. If I can I would just use that.
What I am looking for is a nice, simple explanation of NSURLSession using user/password authentication.

I think your question is vague and underspecified. That said, here's one solution, from here:
-(void)URLSession:(NSURLSession *)session didReceiveChallenge:(NSURLAuthenticationChallenge *)challenge completionHandler:(void (^)( NSURLSessionAuthChallengeDisposition disposition, NSURLCredential *credential))completionHandler
{
if (_sessionFailureCount == 0) {
NSURLCredential *cred = [NSURLCredential credentialWithUser:self.userName password:self.password persistence:NSURLCredentialPersistenceNone];
completionHandler(NSURLSessionAuthChallengeUseCredential, cred);
} else {
completionHandler(NSURLSessionAuthChallengeCancelAuthenticationChallenge, nil);
}
_sessionFailureCount++;
}
I strongly recommend that you read and re-read the Apple docs on this.

For me the following code works:
NSString *userName=#"user:";
NSString *userPassword=#"password";
NSString *authStr= [userName stringByAppendingString:userPassword];
NSString *url=#"http://000.00.0.0:0000/service.json";
NSData *authData = [authStr dataUsingEncoding:NSUTF8StringEncoding];
NSString *authValue = [NSString stringWithFormat: #"Basic %#",[authData base64EncodedStringWithOptions:0]];
NSMutableURLRequest* request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:url]];
[request setValue:authValue forHTTPHeaderField:#"Authorization"];
[NSURLConnection sendAsynchronousRequest:request
queue:[NSOperationQueue mainQueue]
completionHandler:^(NSURLResponse *response,
NSData *data, NSError *connectionError)
NSDictionary *theDictionary = [NSJSONSerialization JSONObjectWithData:data
options:0
error:NULL];
NSDictionary *host = [theDictionary objectForKey : #"host"];
// json nested
self.label.text = [host objectForKey:#"key1"];
self.label.text = [host objectForKey:#"key2"];
regards

Related

An instance of class UITextField was deallocated while key value observers were still registered with it.

Hello i am getting this error
An instance 0x18872c0 of class UITextField was deallocated while key value observers were still registered with it. Observation info was leaked, and may even become mistakenly attached to some other object. Set a breakpoint on NSKVODeallocateBreak to stop here in the debugger.
I am observing changes made on a textfield in ViewDidLoad
[textNumber addObserver:self forKeyPath:#"text" options:0 context:nil];
this responds at here
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object
change:(NSDictionary *)change context:(void *)context {
if (textNumber.text.length==0) {
[buttonMakeAudioCall setImage:[UIImage imageNamed:#"off_green_btn.png"] forState:UIControlStateNormal];
buttonMakeAudioCall.userInteractionEnabled=NO;
}else{
[buttonMakeAudioCall setImage:[UIImage imageNamed:#"green_btn.png"] forState:UIControlStateNormal];
buttonMakeAudioCall.userInteractionEnabled=YES;
}
}
Unfortunately app crashes inside the following method when response comes.
NSURL *url = [NSURL URLWithString:string];
NSURLRequest *request = [NSURLRequest requestWithURL:url];
[NSURLConnection sendAsynchronousRequest:request
queue:[NSOperationQueue mainQueue]
completionHandler:^(NSURLResponse *response,
NSData *data, NSError *connectionError)
{
if (data.length > 0 && connectionError == nil)
{
NSDictionary *greeting = [NSJSONSerialization JSONObjectWithData:data
options:0
error:NULL];
NSString *balance = [greeting objectForKey:#"balance"];
NSLog(#"balance is %#",balance);
labelStatus.text=[NSString stringWithFormat:#"%#€",balance];
}
}];
What i understood is textfield object/observer is released at some point and i need to handle it.But how?I am using ARC.If somebody who knows better could provide more information on the situation,i could handle it.
I found out the reason.It was a mistake from my side.Just before entering this view controller ,I'm calling a method. where I'm writing the following code.
NSURL *url = [NSURL URLWithString:string];
NSURLRequest *request = [NSURLRequest requestWithURL:url];
[NSURLConnection sendAsynchronousRequest:request
queue:[NSOperationQueue mainQueue]
completionHandler:^(NSURLResponse *response,
NSData *data, NSError *connectionError)
{
if (data.length > 0 && connectionError == nil)
{
NSDictionary *greeting = [NSJSONSerialization JSONObjectWithData:data options:0 error:NULL];
NSString *sipserver = [greeting objectForKey:#"ip"];
NSString *port = [greeting objectForKey:#"port"];
NSString *control_url = [greeting objectForKey:#"control_url"];
NSString *version = [greeting objectForKey:#"version"];
[[NSUserDefaults standardUserDefaults] synchronize];
[self.navigationController popViewControllerAnimated:YES];
[[NSUserDefaults standardUserDefaults]setBool:YES forKey:#"login"];
The problem is this line.
[self.navigationController popViewControllerAnimated:YES];
Im poping a parent view controller of the current view controller.Because i've used blocks,this happens like this.Anyhow i found out the solution.This had nothing to do with textfield or key value observer.Hope this answer helps some one .Thanks.

how could i integrate via me social site into iphone app

hi i want to integrate Via Me social site into my iphone app,i googled but didn't find any samples.
The basic process is as follows:
Create a custom URL scheme for your app. Via Me will use this after the user has been authenticated, to return to your app. In my example, I created one called "robviame://"
Register your app at http://via.me/developers. This will give you a client id and a client secret:
When you want to authenticate the user, you call:
NSString *redirectUri = [[self redirectURI] stringByAddingPercentEscapesForURLParameterUsingEncoding:NSUTF8StringEncoding];
NSString *urlString = [NSString stringWithFormat:#"https://api.via.me/oauth/authorize/?client_id=%#&redirect_uri=%#&response_type=code", kClientID, redirectUri];
NSURL *url = [NSURL URLWithString:urlString];
[[UIApplication sharedApplication] openURL:url];
What that will do is fire up your web browser and give the user a chance to log on and grant permissions to your app. When user finishes that process, because you've defined your custom URL scheme, it will call the following method in your app delegate:
- (BOOL)application:(UIApplication *)application openURL:(NSURL *)url sourceApplication:(NSString *)sourceApplication annotation:(id)annotation
{
// do whatever you want here to parse the code provided back to the app
}
for example, I'll call a handler for my Via Me response:
- (BOOL)application:(UIApplication *)application openURL:(NSURL *)url sourceApplication:(NSString *)sourceApplication annotation:(id)annotation
{
ViaMeManager *viaMeManager = [ViaMeManager sharedManager];
if ([[url host] isEqualToString:viaMeManager.host])
{
[viaMeManager handleViaMeResponse:[self parseQueryString:[url query]]];
return YES;
}
return NO;
}
// convert the query string into a dictionary
- (NSDictionary *)parseQueryString:(NSString *)query
{
NSMutableDictionary *dictionary = [[NSMutableDictionary alloc] init];
NSArray *queryParameters = [query componentsSeparatedByString:#"&"];
for (NSString *queryParameter in queryParameters) {
NSArray *elements = [queryParameter componentsSeparatedByString:#"="];
NSString *key = [elements[0] stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSString *value = [elements[1] stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
value = [[value componentsSeparatedByString:#"+"] componentsJoinedByString:#" "];
[dictionary setObject:value forKey:key];
}
return dictionary;
}
That handler might, for example, save the code and then request the access token:
- (void)handleViaMeResponse:(NSDictionary *)parameters
{
self.code = parameters[#"code"];
if (self.code)
{
// save the code
[[NSUserDefaults standardUserDefaults] setValue:self.code forKey:kViaMeUserDefaultKeyCode];
[[NSUserDefaults standardUserDefaults] synchronize];
// now let's authenticate the user and get an access key
[self requestToken];
}
else
{
NSLog(#"%s: parameters = %#", __FUNCTION__, parameters);
NSString *errorCode = parameters[#"error"];
if ([errorCode isEqualToString:#"access_denied"])
{
[[[UIAlertView alloc] initWithTitle:nil
message:#"Via Me functions will not be enabled because you did not authorize this app"
delegate:nil
cancelButtonTitle:#"OK"
otherButtonTitles:nil] show];
}
else
{
[[[UIAlertView alloc] initWithTitle:nil
message:#"Unknown Via Me authorization error"
delegate:nil
cancelButtonTitle:#"OK"
otherButtonTitles:nil] show];
}
}
}
and the code to retrieve the token might look like:
- (void)requestToken
{
NSURL *url = [NSURL URLWithString:#"https://api.via.me/oauth/access_token"];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
[request setHTTPMethod:#"POST"];
NSDictionary *paramsDictionary = #{#"client_id" : kClientID,
#"client_secret" : kClientSecret,
#"grant_type" : #"authorization_code",
#"redirect_uri" : [self redirectURI],
#"code" : self.code,
#"response_type" : #"token"
};
NSMutableArray *paramsArray = [NSMutableArray array];
[paramsDictionary enumerateKeysAndObjectsUsingBlock:^(NSString *key, NSString *obj, BOOL *stop) {
[paramsArray addObject:[NSString stringWithFormat:#"%#=%#", key, [obj stringByAddingPercentEscapesForURLParameterUsingEncoding:NSUTF8StringEncoding]]];
}];
NSData *paramsData = [[paramsArray componentsJoinedByString:#"&"] dataUsingEncoding:NSUTF8StringEncoding];
[request setHTTPBody:paramsData];
NSOperationQueue *queue = [[NSOperationQueue alloc] init];
[NSURLConnection sendAsynchronousRequest:request queue:queue completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) {
if (error)
{
NSLog(#"%s: NSURLConnection error = %#", __FUNCTION__, error);
return;
}
NSError *parseError;
id results = [NSJSONSerialization JSONObjectWithData:data options:0 error:&parseError];
if (parseError)
{
NSLog(#"%s: NSJSONSerialization error = %#", __FUNCTION__, parseError);
return;
}
self.accessToken = results[#"access_token"];
if (self.accessToken)
{
[[NSUserDefaults standardUserDefaults] setValue:self.accessToken forKey:kViaMeUserDefaultKeyAccessToken];
[[NSUserDefaults standardUserDefaults] synchronize];
}
}];
}
Hopefully this will be enough to get you going. This is described in greater detail at the http://via.me/developers page.

send parameter values and retrieve an xml file Xcode

In my current xcode project, I need to send parameter values to a url and need to retrieve an xml file based on the parameter values sent.
I tried the below code but it's not working:
(IBAction)myButtonClick:(id)sender
{
NSURL *oRequestURL =
[NSURL URLWithString:#"http://xyz .com/air/1.0/search?from=MAA&to=CJB&depart-date=2012-06-30&adults=2&children=2&infants=1&way=one&cabin-type=Economy&sort=asc"];
NSMutableURLRequest *oRequest = [[[NSMutableURLRequest alloc]init]autorelease];
[oRequest setHTTPMethod:#"POST"];
[oRequest setURL: oRequestURL];
NSMutableData *oHttpBody = [NSMutableData data];
[oHttpBody appendData:[#"This is HTTP Request body" dataUsingEncoding:NSUTF8StringEncoding]];
[oRequest setValue:[oHttpBody length] forHTTPHeaderField:#"Content-Length"];
NSError *oError = [[NSError alloc]init];
NSHTTPURLResponse *oResponseCode = nil;
NSData *oResponseData = [NSURLConnection sendSynchronousRequest:oRequest returningResponse:oResponseCode error:oError];
if ([oResponseCode statusCode]> 200) {
NSLog(#"Status code is greater than 200");
}
NSString *strResult=[[NSString alloc]initWithData:oResponseData encoding:NSUTF8StringEncoding];
NSLog(#"The result is %s",strResult);
}
I have searched many sites and books but could not find a solution.
Would be of great help if a link to a tutorial or some other useful resource can be provided. Appreciate your great help.
Thank You.
Hi,
I have found the solution. The code is as below. Hope it helps someone else:)
- (IBAction)myButtonPressed:(id)sender
{
NSString *urlAsString = #"http://api.abc.com/air/1.0/search?from=MAA&to=CJB&depart-date=2012-09-30&adults=2&children=2&infants=1&way=one&cabin-type=Economy&sort=asc";
NSURL *url = [NSURL URLWithString:urlAsString];
NSMutableURLRequest *urlRequest = [NSMutableURLRequest requestWithURL:url];
[urlRequest setValue:#"2193141de2g7e2a34bb19bc3aa52b3b5" forHTTPHeaderField:#"X-XX-API-KEY"];
[urlRequest setTimeoutInterval:30.0f];
[urlRequest setHTTPMethod:#"GET"];
NSOperationQueue *queue = [[NSOperationQueue alloc]init];
[NSURLConnection
sendAsynchronousRequest:urlRequest queue:queue completionHandler:^(NSURLResponse *response, NSData *data, NSError *error)
{
if ([data length]>0 &&
error == nil)
{
NSString *html = [[NSString alloc]initWithData:data encoding:NSUTF8StringEncoding];
NSLog(#"HTML = %#", html);
}
else if ([data length]== 0 && error==nil) {
NSLog(#"Nothing was downloaded");
}
else if (error!= nil) {
NSLog(#"Error occured = %#", error);
}
}];
}

Why does my code break for one call to this method, but not another?

I have a Mac application that is supposed to fetch Twitter followers and friends for a given username and then, in turn, ask Twitter for the user NAMES for each of those returned UserIDs. As you can see below, I have a method that will call the Twitter API to get friends/followers (which works fine). It is the userNameForUserID:delegate: method that is causing me problems. I used to do these requests synchronously and return the NSString for the username right then. That (now commented out) line always broke, so I tried doing it with an NSURLConnection asynchronously. Still doesn't work. I don't understand why
[[NSString alloc] initWithContentsOfURL:...] works for the fetchFollowers... method, but not when I do it the EXACT SAME way in the other...
I put a break point on the line that used to alloc init the NSString with contents of URL, and when I step into it, it doesn't break, return, throw an exception, crash...nothing. It's as if that line just got stepped over (but my application is still blocked.
Any ideas? Much appreciated!
NSString * const GET_FOLLOWERS = #"https://api.twitter.com/1/followers/ids.json?cursor=-1&screen_name=";
NSString * const GET_FRIENDS = #"https://api.twitter.com/1/friends/ids.json?cursor=-1&screen_name=";
NSString * const GET_USER_INFO = #"https://api.twitter.com/1/users/show.json?user_id=";
#implementation TwitterAPI
+ (void)userNameForUserID:(NSNumber *)userID delegate:(id<UserNameDelegate>)delegate
{
NSURL *url = [NSURL URLWithString:[GET_USER_INFO stringByAppendingString:[userID stringValue]]];
// NSString *JSON = [[NSString alloc] initWithContentsOfURL:url encoding:NSUTF8StringEncoding error:&error];
NSURLRequest *req = [NSURLRequest requestWithURL:url];
NSOperationQueue *queue = [[NSOperationQueue alloc] init];
[NSURLConnection sendAsynchronousRequest:req queue:queue completionHandler:^(NSURLResponse *urlResponse, NSData *data, NSError *error) {
[delegate addUserNameToArray:data];
}];
}
+ (NSArray *)fetchFollowersWithUserName:(NSString *)userName
{
NSURL *url = [NSURL URLWithString:[GET_FOLLOWERS stringByAppendingString:userName]];
NSArray *followerIDs;
NSString *JSON = [[NSString alloc] initWithContentsOfURL:url encoding:NSASCIIStringEncoding error:nil];
if ([JSON rangeOfString:#"error"].location == NSNotFound)
followerIDs = [[JSON JSONValue] valueForKey:#"ids"];
return followerIDs;
}

leaks when using NSData, NSURL,NSMutableURLRequest,NSURLConnection and sendSynchronousRequest

I am getting the leak at this line in below code" NSData *returnData = [NSURLConnection ..........."
NSURL *finalURL = [NSURL URLWithString:curl];
NSMutableURLRequest *theRequest = [NSMutableURLRequest requestWithURL:finalURL
cachePolicy:NSURLRequestReloadIgnoringCacheData
timeoutInterval:10];
[theRequest setHTTPMethod:#"GET"];
NSData *returnData = [NSURLConnection sendSynchronousRequest:theRequest returningResponse:nil error:nil];
BOOL enabled = [self getAutoGenerateObject:returnData];
return enabled;
please help me out of this problem.
Thank You,
Madan Mohan
You will need to release the returnData. That's why in Apple's examples in 'URL Loading Programming Guide / Using NSURLConnection', the returnData is assigned to an iVar and release in dealloc or connectionDidFinishLoading in the case of Asynchronous communication.
Depending what operation you are performing in you method getAutoGeneratedObject, but in theory it can take ownership there.
You could also mark returnData as autoreleased, but that is not always recommended especially if the response data is large.
NSURL *finalURL = [NSURL URLWithString:curl];
NSMutableURLRequest *theRequest = [NSMutableURLRequest requestWithURL:finalURL
cachePolicy:NSURLRequestReloadIgnoringCacheData
timeoutInterval:10];
[theRequest setHTTPMethod:#"GET"];
NSData *returnData = [NSURLConnection sendSynchronousRequest:theRequest returningResponse:nil error:nil];
BOOL enabled = [self getAutoGenerateObject:returnData];
[returnData release];
return enabled;

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