I am developing a very simple application which accesses a written url. So i am wondering what is the difference between access by nsurlconnection and access by just using browser. cause some sites respond but they don`t send data when i used the nsurlconnection.
- (void)getWikiData:(NSString *)keyword{
NSString* tmpURL = #"http://wikipedia.simpleapi.net/api?keyword=";
NSString* encodedString;
CFStringRef strRef = CFURLCreateStringByAddingPercentEscapes(NULL, (CFStringRef)keyword, NULL, (CFStringRef)#"!*'();:#&=+$,/?%#[]~", kCFStringEncodingUTF8);
encodedString = [NSString stringWithString:(NSString *)strRef];
CFRelease(strRef);
[tmpURL stringByAppendingString:encodedString];
[tmpURL stringByAppendingString:#"&output=html"];
NSURL *url = [NSURL URLWithString:tmpURL];
NSString *userAgent = #"Custom User Agent";
NSMutableURLRequest *request = [[[NSMutableURLRequest alloc] initWithURL:url] autorelease];
[request setValue:userAgent forHTTPHeaderField:#"User-Agent"];
connection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
}
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSHTTPURLResponse *)response{
NSLog(#"Receive Response");
}
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data{
NSLog(#"Receive Data");
}
Thanks in advance.
The difference is in the user agent string of the resulting application. MobileSafari reports itself as "Safari, iOS like Mac OS X", however, a plain NSURLConnection sends a CFNetwork description, which is not very useful for most sites to do 'browser' (rather 'client') detection, that's why they may refuse to send data to an unrecognized user agent.
Related
I am trying to access protected resources on a Django site using NSURLConnection , OAuth2 Bearer token and HTTPS. I receive a token, which I then attach either to a GET parameter, POST parameter or header. I can access those URL:s which respond to GET parameter. But when I try to access urls using POST, the server returns me a 403 with a custom error message saying there is no header/post parameter containing the token. I have tried several solutions and HTTP libraries. This method uses AFNetworking, I tried it. We even changed the authorization to accept an alternative header due to warnings that apple does not like the modifying of "Authorization" header. My current code looks like this: (scheme == #"https")
-(void) logOut {
NSString *pget = #"/api/logout/";
NSString *path = [pget stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSString *absolutePath = [NSString stringWithFormat:#"%#://%#%#", scheme, host, path];
NSURL *url = [NSURL URLWithString:absolutePath];
NSMutableURLRequest *urlRequest = [NSMutableURLRequest requestWithURL:url cachePolicy:NSURLRequestReloadIgnoringLocalCacheData timeoutInterval:30.0];
NSString *authValue = [NSString stringWithFormat:#"Bearer %#", accessToken];
[urlRequest setValue:authValue forHTTPHeaderField:#"Authorization_Extra"];
[urlRequest setValue:#"application/x-www-form-urlencoded; charset=utf-8" forHTTPHeaderField:#"content-type"];
[urlRequest setHTTPMethod: #"POST"];
/*
NSString *post = [NSString stringWithFormat:#"access_token_extra=%#", accessToken];
NSData *postData = [post dataUsingEncoding:NSASCIIStringEncoding];
NSString *postLength = [NSString stringWithFormat:#"%lu", (unsigned long)[postData length]];
[urlRequest setValue:postLength forHTTPHeaderField:#"Content-Length"];
[urlRequest setHTTPBody:postData];
*/
NSDictionary* headers = [urlRequest allHTTPHeaderFields];
NSLog(#"headers: %#",headers);
_originalRequest = urlRequest;
NSURLConnection* connection = [[NSURLConnection alloc] initWithRequest:urlRequest delegate:self startImmediately:NO];
[connection start];
}
#pragma mark NSURLConnection Delegate Methods
- (NSURLRequest *)connection: (NSURLConnection *)connection
willSendRequest: (NSURLRequest *)request
redirectResponse: (NSURLResponse *)redirectResponse;
{
if (redirectResponse) {
// we don't use the new request built for us, except for the URL
NSURL *newURL = [request URL];
NSMutableURLRequest *newRequest = [_originalRequest mutableCopy];
[newRequest setURL: newURL];
NSLog(#"New Request headers: %#", [newRequest allHTTPHeaderFields]);
return newRequest;
} else {
return request;
}
}
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSHTTPURLResponse *)response {
NSLog(#"Received response statuscode: %ld", (long)[response statusCode]);
responseData = [[NSMutableData alloc] init];
}
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
[responseData appendData:data];
}
- (NSCachedURLResponse *)connection:(NSURLConnection *)connection
willCacheResponse:(NSCachedURLResponse*)cachedResponse {
return nil;
}
- (void)connectionDidFinishLoading:(NSURLConnection *)connection {
NSLog(#"connection finished:");
[_delegate handleData:responseData];
}
The _Delegate handleData parses the response, and the custom response is always that I am lacking either the header or post parameter needed for the Bearer token.
It seems that even though I am replacing the request with a mutable copy of the original on every redirect, the headers/parameters still get stripped by NSURLConnection. But why, and how, since I'm sending a copy of the original request every time and I verify by logging that they are there?
I have a little Mac application which should be able to post Data to my web server which saves the data in a database. Now that's the Code I have now:
NSData *postData = [urlString dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];
NSString *postLength = [NSString stringWithFormat:#"%d", [postData length]];
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
[request setURL:[NSURL URLWithString:#"http://..."]];
[request setHTTPMethod:#"POST"];
[request setValue:postLength forHTTPHeaderField:#"Content-Length"];
[request setValue:#"application/x-www-form-urlencoded" forHTTPHeaderField:#"Content-Type"];
[request setHTTPBody:postData];
NSURLConnection * connection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
if (connection) NSLog(#"Done");
And it works fine. But now I want to check whether the data was correct (and stored in the database) or something (like eMail) is wrong. The PHP file prints e.g. "email incorrect" out if the E-Mail is not correct.
But how can I fetch this data (which PHP prints out) in Xcode that the App knows whether it was successful or not?
Thanks for answers!
You need to implement the NSURLConnectionDelegate methods connection:didReceiveData: and connectionDidFinishLoading:
According to the docs didReceiveData: may be called multiple times per NSURLRequest (i.e. the response will not always arrive all at once) so the recommended method is to append the incoming data to buffer during connection:didReceiveData: and then do any processing on the data in connectionDidFinishLoading:.
You could create a property on your class like this:
#property (nonatomic, strong) NSMutableData *dataBuffer;
And instantiate your buffer during viewDidLoad:
- (void)viewDidLoad
{
[super viewDidLoad];
self.dataBuffer = [[NSMutableData alloc] init];
// do any other setup your class requires...
}
And then implement the delegate methods:
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
// clear the buffer in case it has been used previously
[self.dataBuffer setLength:0];
}
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
[self.dataBuffer appendData:data];
}
- (void)connectionDidFinishLoading:(NSURLConnection*)connection
{
NSString *response = [NSString stringWithUTF8String:[self.dataBuffer bytes]]);
NSLog(#"response from HTTP request=>%#", response);
}
This can all also be done using a third-party networking library like ASIHTTPRequest (which is no longer under active develoment) or AFNetworking, but sometimes those can be overkill depending upon what you are trying to accomplish
Implement the delegate method for the NSURLConnection,
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response.
This method is called by the app when the request finishes. You can access response data using the 'response' parameter.
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data;
Then just convert the 'data' parameter into a string using:
NSString *responseString = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
Then you can search the response for whatever string you want, e.g., "email incorrect".
PS: I generally don't use NSURLConnection/NSURLRequest for HTTP requests, I'd recommend you check out ASIHTTPRequest for really simple HTTP requests/connections.
Hope this helps.
I'm a novice in iOS developing, and have some problems with understanding web service organization. I want to send a Get query to the URL. And I do it so:
-(BOOL) sendLoginRequest{
NSString *getAction = [NSString stringWithFormat:#"action=%#&username=%password=%#",#"login",self.log.text, self.pass.text];
NSString *getUserName = [NSString stringWithFormat:#"username=%#",self.log.text];
NSString *getPassword = [NSString stringWithFormat:#"username=%#",self.pass.text];
NSData *getDataAction = [getAction dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];
NSString *getLengthAction = [NSString stringWithFormat:#"%d", [getDataAction length]];
NSMutableURLRequest *request = [[[NSMutableURLRequest alloc] init] autorelease];
[request setURL:[NSURL URLWithString:#"http:http://www.site.fi/api/"]];
[request setHTTPMethod:#"GET"];
[request setValue:getLengthAction forHTTPHeaderField:#"Content-Length"];
[request setValue:#"application/x-www-form-urlencoded" forHTTPHeaderField:#"Content-Type"];
[request setHTTPBody:getLengthAction];
self.urlConnection = [[[NSURLConnection alloc] initWithRequest:request delegate:self] autorelease];
NSAssert(self.urlConnection != nil, #"Failure to create URL connection.");
// show in the status bar that network activity is starting
[UIApplication sharedApplication].networkActivityIndicatorVisible = YES;
}
the answer may be "true" or "false"
but how can I take this answer?
You should define next methods to get answer:
Start connection: [self.urlConnection start];
Check server response:
- (void)connection:(NSURLConnection *)theConnection didReceiveResponse:(NSURLResponse *)response
Collect data that servers sends you:
- (void)connection:(NSURLConnection *)theConnection didReceiveData:(NSData *)data
Be sure to manage errors:
- (void)connection:(NSURLConnection *)theConnection didFailWithError:(NSError *)error
Check received data:
- (void)connectionDidFinishLoading:(NSURLConnection *)theConnection
To be more sure that you correctly understood me check NSURLConnection Class Reference
Send [self.urlConnection start]; and implement the NSURLConnectionDelegate methods to receive the response. Alternatively use ASIHTTPRequest and the block handlers, which to my way of thinking are much easier to write for beginners, provided you don't need to run on iOS pre-4.1.
You will gather the data returned as NSData; just convert that to a string, and either call boolValue on the string (check the docs for its rather strange tests), or use a specific set of your own tests.
I would like to get the Mime Type of a url synchronously. I don't want to use NSURLConnection.
Just something like:
NSString *theMimeType = [self getMimeTypeFromURL:theURL];
Any ideas?
There is absolutely no reason not to use asynchronous requests.
Use NSURLConnection's delegate approach.
NSString *url = ...;
NSURLRequest *req = [NSURLRequest requestWithURL:[NSURL URLWithString:url]];
NSURLConnection *conn = [NSURLConnection connectionWithRequest:req delegate:self];
[conn start];
Somewhere else in your #implementation:
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response {
NSString *mime = [response MIMEType];
//do something with mime
}
I am writing a program in Objective-C and I need to make web requests to web server, but asynchronously and I am fairly new on mac, I am very good at windows technologies, but I need to know that if I use NSOperation (introduced in 10.5, i am assuming that it will not run in 10.4 MAC?), or if it was implemented such that it utilizes system threading which will be available on 10.4?
Or I should create a new thread and create a new runloop, also how to use cookies etc, if anyone can give me one small example, that will be of great help. I want this sample to run on mac 10.4 too if possible.
There's a good example of using NSURLRequest and NSHTTPCookies to do a full web application example of logging into a website, storing the SessionID cookie and resubmitting it in future requests.
NSURLConnection, NSHTTPCookie
By logix812:
NSHTTPURLResponse * response;
NSError * error;
NSMutableURLRequest * request;
request = [[[NSMutableURLRequest alloc] initWithURL:[NSURL URLWithString:#"http://temp/gomh/authenticate.py?setCookie=1"]
cachePolicy:NSURLRequestReloadIgnoringCacheData
timeoutInterval:60] autorelease];
[NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error];
NSLog(#"RESPONSE HEADERS: \n%#", [response allHeaderFields]);
// If you want to get all of the cookies:
NSArray * all = [NSHTTPCookie cookiesWithResponseHeaderFields:[response allHeaderFields] forURL:[NSURL URLWithString:#"http://temp"]];
NSLog(#"How many Cookies: %d", all.count);
// Store the cookies:
// NSHTTPCookieStorage is a Singleton.
[[NSHTTPCookieStorage sharedHTTPCookieStorage] setCookies:all forURL:[NSURL URLWithString:#"http://temp"] mainDocumentURL:nil];
// Now we can print all of the cookies we have:
for (NSHTTPCookie *cookie in all)
NSLog(#"Name: %# : Value: %#, Expires: %#", cookie.name, cookie.value, cookie.expiresDate);
// Now lets go back the other way. We want the server to know we have some cookies available:
// this availableCookies array is going to be the same as the 'all' array above. We could
// have just used the 'all' array, but this shows you how to get the cookies back from the singleton.
NSArray * availableCookies = [[NSHTTPCookieStorage sharedHTTPCookieStorage] cookiesForURL:[NSURL URLWithString:#"http://temp"]];
NSDictionary * headers = [NSHTTPCookie requestHeaderFieldsWithCookies:availableCookies];
// we are just recycling the original request
[request setAllHTTPHeaderFields:headers];
request.URL = [NSURL URLWithString:#"http://temp/gomh/authenticate.py"];
error = nil;
response = nil;
NSData * data = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error];
NSLog(#"The server saw:\n%#", [[[NSString alloc] initWithData:data encoding: NSASCIIStringEncoding] autorelease]);
For asynchronous requests, you need to use NSURLConnection.
For cookies, see NSHTTPCookie and NSHTTPCookieStorage.
UPDATE:
The code below is real, working code from one of my applications. responseData is defined as NSMutableData* in the class interface.
- (void)load {
NSURL *myURL = [NSURL URLWithString:#"http://stackoverflow.com/"];
NSURLRequest *request = [NSURLRequest requestWithURL:myURL
cachePolicy:NSURLRequestReloadIgnoringLocalCacheData
timeoutInterval:60];
[[NSURLConnection alloc] initWithRequest:request delegate:self];
}
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response {
responseData = [[NSMutableData alloc] init];
}
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
[responseData appendData:data];
}
- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error {
[responseData release];
[connection release];
// Show error message
}
- (void)connectionDidFinishLoading:(NSURLConnection *)connection {
// Use responseData
[responseData release];
[connection release];
}
I am able to fetch cookie in such way:
NSArray* arr = [[NSHTTPCookieStorage sharedHTTPCookieStorage] cookiesForURL:[NSURL URLWithString: #"http://google.com" ]];
This one works fine for asynchronous request as well.