Restful API call using IOS with authentication

Question

I am working on an application that uses restful API call using prestashop API. I am new at IOS I coded the same method in android as:

    InputStream is = null;
try {

 DefaultHttpClient client = new DefaultHttpClient();  

    /* adding credentials as it is RESTful call */
    String username = "xyz";
    String password = "";
    client.getCredentialsProvider().setCredentials(new AuthScope(AuthScope.ANY_HOST, AuthScope.ANY_PORT),new UsernamePasswordCredentials(username, password));  
// HTTP get request       
HttpGet get = new HttpGet("http://www.example.com/api/");
HttpResponse responseGet;
responseGet = client.execute(get);
is = responseGet.getEntity().getContent();
} catch (ClientProtocolException e) {
    Log.e("HTTP Request","Client Protocol exception" );
} catch (IOException e) {
    Log.e("HTTP Request","IO exception" );
}

It is working perfectly for Android. For IOS I used this coding but I am not getting data from the server.

NSString *userName = @"XYZ";
NSString *password = @"";
//setting the string of the url taking from appliance IP.

NSString *urlString = @"http://www.example.com/api/";

NSMutableURLRequest *request= [[NSMutableURLRequest alloc] init];

[request setURL:[NSURL URLWithString:urlString]];

[request setHTTPMethod:@"GET"];

NSString *str1 = [NSString stringWithFormat:@"%@:%@",userName,password];

NSLog(@" str1 %@", str1);

[request addValue:[NSString stringWithFormat:@"Basic %@",str1] forHTTPHeaderField:@"Authorization"];

NSData *returnData = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];

NSString *str = [[NSString alloc] initWithData:returnData encoding:NSUTF8StringEncoding];
NSLog(@"str: %@", str);

please tell me what I am doing wrong and provide any solution.

Thanks!

Answer 1

You can build the URL string this way and it should work :-

NSString *str1 = [NSString stringWithFormat:@"http://%@:%@@www.example.com/api",userName,password];

No need to use the HTTP header fields I believe

Answer 2

Username and password need to be encoded using Base64 encoding when using Basic HTTP authentication.

From Wikipedia's Article on that subject:

Client side

When the user agent wants to send the server authentication credentials it may use the Authorization header.

The Authorization header is constructed as follows:[6] Username and password are combined into a string "username:password"

The resulting string literal is then encoded using Base64

The authorization method and a space i.e. "Basic " is then put before the encoded string. For example, if the user agent uses 'Aladin' as the username and 'sesam open' as the password then the header is formed as follows:

Authorization: Basic QWxhZGluOnNlc2FtIG9wZW4=

---

See this corrected code:

[...]
NSString *str1 = [NSString stringWithFormat:@"%@:%@",userName,password];
NSString *encodedString = [self stringByBase64EncodingWithString:str1];
[request addValue:[NSString stringWithFormat:@"Basic %@",encodedString] forHTTPHeaderField:@"Authorization"];
[...]


- (NSString *)stringByBase64EncodingWithString:(NSString *)inString
{
    NSData *data = [NSData dataWithBytes:[inString UTF8String] 
                                  length:[inString lengthOfBytesUsingEncoding:NSUTF8StringEncoding]];
    NSUInteger length = [data length];
    NSMutableData *mutableData = [NSMutableData dataWithLength:((length + 2) / 3) * 4];

    uint8_t *input = (uint8_t *)[data bytes];
    uint8_t *output = (uint8_t *)[mutableData mutableBytes];

    for (NSUInteger i = 0; i < length; i += 3) 
    {
        NSUInteger value = 0;
        for (NSUInteger j = i; j < (i + 3); j++) 
        {
            value <<= 8;
            if (j < length) 
            {
                value |= (0xFF & input[j]); 
            }
        }

        static uint8_t const base64EncodingTable[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";

        NSUInteger idx = (i / 3) * 4;
        output[idx + 0] = base64EncodingTable[(value >> 18) & 0x3F];
        output[idx + 1] = base64EncodingTable[(value >> 12) & 0x3F];
        output[idx + 2] = (i + 1) < length ? base64EncodingTable[(value >> 6)  & 0x3F] : '=';
        output[idx + 3] = (i + 2) < length ? base64EncodingTable[(value >> 0)  & 0x3F] : '=';
    }
    return [[NSString alloc] initWithData:mutableData encoding:NSASCIIStringEncoding];
}