Here is my solution for a better synchronous NSURLConnection. Although asynchronous NSURLConnections are usually a good way to go, sometimes there is just no way around waiting (and blocking) until a request finished. NSURLConnection offers a method to perform synchronous requests, but it is far from perfect and has some serious flaws. In my cas…

URLConnection.h

#import <Foundation/Foundation.h>

@interface URLConnection : NSObject <NSURLConnectionDataDelegate, NSURLConnectionDelegate>

+ (NSData *)sendSynchronousRequest:(NSURLRequest *)request
                 returningResponse:(NSURLResponse **)response
                             error:(NSError **)error;

@end

URLConnection.m

#import "URLConnection.h"

@interface URLConnection ()
@property(nonatomic, strong) NSURLConnection *connection;
@property(nonatomic, strong) NSURLResponse *response;
@property(nonatomic, strong) NSData *responseData;
@property(nonatomic, strong) NSCondition *condition;
@property(nonatomic, strong) NSError *error;
@property(nonatomic) BOOL connectionDidFinishLoading;
@end

@implementation URLConnection

+ (NSData *)sendSynchronousRequest:(NSURLRequest *)request
                 returningResponse:(NSURLResponse **)response
                             error:(NSError **)error {
    return [[[URLConnection alloc] init] sendSynchronousRequest:request returningResponse:response error:error];
}

- (id)init {
    self = [super init];
    if (self) {
        self.condition = [[NSCondition alloc] init];
        self.connection = nil;
        self.connectionDidFinishLoading = NO;
        self.error = nil;
        self.response = nil;
        self.responseData = [NSData data];
    }
    return self;
}

- (NSData *)sendSynchronousRequest:(NSURLRequest *)request
                 returningResponse:(NSURLResponse **)response
                             error:(NSError **)error {
    NSParameterAssert(request);
    NSAssert(!self.connection, @"This method may only be called once");
    self.connection = [[NSURLConnection alloc] initWithRequest:request delegate:self startImmediately:NO];
    [self.connection setDelegateQueue:[[NSOperationQueue alloc] init]];
    [self.connection start];
    [self waitForConnectionToFinishLoading];
    if (self.error != nil) {
        if (response) *response = nil;
        if (error) *error = self.error;
        return nil;
    } else {
        if (response) *response = self.response;
        if (error) *error = nil;
        return self.responseData;
    }
}

- (void)waitForConnectionToFinishLoading {
    [self.condition lock];
    while (!self.connectionDidFinishLoading) {
        [self.condition wait];
    }
    [self.condition unlock];
}

- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response {
    self.response = response;
}

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
    NSMutableData *mutableResponse = self.responseData.mutableCopy;
    [mutableResponse appendData:data];
    self.responseData = mutableResponse.copy;
}

- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error {
    [self.condition lock];
    self.error = error;
    self.connectionDidFinishLoading = YES;
    [self.condition signal];
    [self.condition unlock];    
}

- (void)connectionDidFinishLoading:(NSURLConnection *)connection {
    [self.condition lock];
    self.connectionDidFinishLoading = YES;
    [self.condition signal];
    [self.condition unlock];
}

@end

Hello. I add didReceiveAuthenticationChallenge but not enter. why?:

• (void)connection:(NSURLConnection *)connection didReceiveAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge {
  if ([challenge.protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodHTTPBasic] || [challenge.protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodNTLM]) {
  if ([challenge previousFailureCount] == 0) {
  NSURLCredential *credential = [NSURLCredential credentialWithUser:@"[email protected]"
  password:@"Abril2020.sap"
  persistence:NSURLCredentialPersistenceForSession];
  [[challenge sender] useCredential:credential forAuthenticationChallenge:challenge];
  }
  else
  {
  [[challenge sender] cancelAuthenticationChallenge:challenge];
  // inform the user that the user name and password
  // in the preferences are incorrect
  NSLog (@"failed authentication");
  // ...error will be handled by connection didFailWithError
  self.error = [NSError errorWithDomain:@"" code:500 userInfo:@{@"Error reason": @"failed authentication"}];
  }
  }
  }

Is NSURLAuthenticationMethodNTLM type
Thx