Cocoa: Handling 407 http response cfnetwork - objective-c

Question

I am creating downloader application.
I am facing a problem with proxy authentication.
I am getting 407 response code i.e proxy authentication required. I have valid proxy authentication details.
Following is Code Flow:
1. Create Http request using CFHTTPMessageCreateRequest
2. Set necessary header field values like Cache-Control, Accept-Ranges, Range & User-Agent using CFHTTPMessageSetHeaderFieldValue
3. Create read stream using CFReadStreamCreateForHTTPRequest
4. Set proxy server URL & port properties on read stream using CFReadStreamSetProperty
5. Set kCFStreamPropertyHTTPShouldAutoredirect to kCFBooleanTrue using CFReadStreamSetProperty
6. open read stream using CFReadStreamOpen
7. In a loop wait for stream to get opened
while (1)
{
if (kCFStreamStatusOpen == CFReadStreamGetStatus)
{
if (CFReadStreamHasBytesAvailable)
{
Get Http response header using CFReadStreamCopyProperty
Get response code using CFHTTPMessageGetResponseStatusCode
if (200 || 206 is response code)
SUCCESS
else check if response code is 407.
}
}
}
I tried using following code
if (407 == nsiStatusCode)
{
CFStreamError err;
cfAuthentication = CFHTTPAuthenticationCreateFromResponse(NULL, cfHttpResponse);
if ((cfAuthentication) && (CFHTTPAuthenticationIsValid(cfAuthentication, &err)))
{
if (CFHTTPAuthenticationRequiresUserNameAndPassword(cfAuthentication))
{
CFHTTPMessageApplyCredentials(cfHttpRequest, cfAuthentication, (CFStringRef)pnsUserName, (CFStringRef)pnsPassword, &err);
}
}
}
but unable to make it work.
How do I handle 407 status code so as to communicate with authenticating HTTP server?
Thanks in advance.
Vaibhav.

Answer 1

Build a CFHTTPMessageRef
-(CFHTTPMessageRef)buildMessage
{
NSURL *myURL = [NSURL URLWithString:#"http://myurl.com"];
NSData *dataToPost = [[NSString stringWithString:#"POST Data It Doesn't Matter What It Is"] dataUsingEncoding:NSUTF8StringEncoding];
//Create with the default allocator (NULL), a post request,
//the URL, and pick either
//kCFHTTPVersion1_0 or kCFHTTPVersion1_1
CFHTTPMessageRef request = CFHTTPMessageCreateRequest(NULL, CSTR("POST"), (CFURLRef)myURL, kCFHTTPVersion1_1);
CFHTTPMessageSetBody(request, (CFDataRef)dataToPost);
//Unfortunately, this isn't smart enough to set reasonable headers for you
CFHTTPMessageSetHeaderFieldValue(request, CFSTR("HOST"), (CFStringRef)[myURL host]);
CFHTTPMessageSetHeaderFieldValue(request, CFSTR("Content-Length"), (CFStringRef)[NSString stringWithFormat:"%d", [dataToPost length]);
CFHTTPMessageSetHeaderFieldValue(request, CFSTR("Content-Type"), CFSTR("charset=utf-8"));
return [NSMakeCollectable(request) autorelease];
}
Send it to the server and read back the response
-(CFHTTPMessageRef)performHTTPRequest:(CFHTTPMessageRef)request
{
CFReadStreamRef requestStream = CFReadStreamCreateForHTTPRequest(NULL, request);
CFReadStreamOpen(requestStream);
NSMutableData *responseBytes = [NSMutableData data];
CFIndex numBytesRead = 0 ;
do
{
UInt8 buf[1024];
numBytesRead = CFReadStreamRead(requestStream, buf, sizeof(buf));
if(numBytesRead > 0)
[responseBytes appendBytes:buf length:numBytesRead];
} while(numBytesRead > 0);
CFHTTPMessageRef response = (CFHTTPMessageRef)CFReadStreamCopyProperty(requestStream, kCFStreamPropertyHTTPResponseHeader);
CFHTTPMessageSetBody(response, (CFDataRef)responseBytes);
CFReadStreamClose(requestStream);
CFRelease(requestStream);
return [NSMakeCollectable(response) autorelease];
}
Adding Authentication to an HTTP Request
-(void)addAuthenticationToRequest:(CFHTTPMessageRef)request withResponse:(CFHTTPMessageRef)response
{
CFHTTPAuthenticationRef authentication = CFHTTPAuthenticationCreateFromResponse(NULL, response);
[NSMakeCollectable(authentication) autorelease];
CFStreamError err;
Boolean success = CFHTTPMessageApplyCredentials(request, authentication, CFSTR("username"), CFSTR("password"), &err);
}
Putting It All Together
-(void)magicHappens
{
CFHTTPMessageRef request = [self buildMessage];
CFHTTPMessageRef response = [self performHTTPRequest: request];
UInt32 statusCode;
statusCode = CFHTTPMessageGetResponseStatusCode(response);
//An HTTP status code of 401 or 407 indicates that authentication is
//required I use an auth count to make sure we don't get stuck in an
//infinite loop if our credentials are bad. Sometimes, making the
//request more than once lets it go through.
//I admit I don't know why.
int authCount = 0;
while((statusCode == 401 || statusCode == 407) && authCount < 3)
{
request = [self buildMessage];
[self addAuthenticationToRequest:request withResponse:response];
response = [self performHTTPRequest: request];
statusCode = CFHTTPMessageGetResponseStatusCode;
authCount++;
}
NSData *responseBodyData = [(NSData*)CFHTTPMessageCopyBody(response) autorelease];
NSString *responseBody = [[[NSString alloc] initWithData:responseBodyData encoding:NSUTF8StringEncoding] autorelease];
NSLog(responseBody);
}
Refer this link.