send device token to server

Question

I have read a lot of tutorials for this and i just wanted ti know if this is right way to do this

- (void)application:(UIApplication*)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData*)deviceToken
{
    NSLog(@"My token is: %@", deviceToken);

    NSString* newToken = [deviceToken description];

    newToken = [newToken stringByTrimmingCharactersInSet:[NSCharacterSet characterSetWithCharactersInString:@"<>"]];
    newToken = [newToken stringByReplacingOccurrencesOfString:@" " withString:@""]; 


    NSString *urlString = [NSString stringWithFormat:@"http://myhost.com./filecreate.php?token=%@",newToken];

    NSURL *url = [[NSURL alloc] initWithString:urlString];

    NSURLRequest *urlRequest = [NSURLRequest requestWithURL:url];

    NSData *urlData;
    NSURLResponse *response;
    urlData = [NSURLConnection sendSynchronousRequest:urlRequest returningResponse:&response error:nil];

}

any advices are more then welcomed.

- (void)application:(UIApplication*)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData*)deviceToken
{

    const char* data = [deviceToken bytes];
    NSMutableString* token = [NSMutableString string];

    for (int i = 0; i < [deviceToken length]; i++) {
        [token appendFormat:@"%02.2hhX", data[i]];
    }


    NSString *urlString = [NSString stringWithFormat:@"http://myhost.com/filecreate.php?token=%@",token];

    NSURL *url = [[NSURL alloc] initWithString:urlString];

    NSURLRequest *urlRequest = [NSURLRequest requestWithURL:url];   
    NSData *urlData;
    NSURLResponse *response;
    urlData = [NSURLConnection sendSynchronousRequest:urlRequest returningResponse:&response error:nil];

}

My application works with both codes, but what's the right way?

Answer 1

As mja said in comments, it's better to add error recovery mechanism (if the request fails you will lose your token) and use asynchronous request (send token in background)

In your AppDelegate.m:

- (void)application:(UIApplication*)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData*)deviceToken
{
    NSString * token = [NSString stringWithFormat:@"%@", deviceToken];
    //Format token as you need:
    token = [token stringByReplacingOccurrencesOfString:@" " withString:@""];
    token = [token stringByReplacingOccurrencesOfString:@">" withString:@""];
    token = [token stringByReplacingOccurrencesOfString:@"<" withString:@""];

    [[NSUserDefaults standardUserDefaults] setObject:token forKey:@"apnsToken"]; //save token to resend it if request fails
    [[NSUserDefaults standardUserDefaults] setBool:NO forKey:@"apnsTokenSentSuccessfully"]; // set flag for request status
    [DataUpdater sendUserToken]; //send token
}

To send token create new class (or use one of existing):
DataUpdater.h

#import <Foundation/Foundation.h>

@interface DataUpdater : NSObject     
+ (void)sendUserToken;
@end

DataUpdater.m

#import "DataUpdater.h"

@implementation DataUpdater

+ (void)sendUserToken {
    if ([[NSUserDefaults standardUserDefaults] boolForKey:@"apnsTokenSentSuccessfully"]) {
        NSLog(@"apnsTokenSentSuccessfully already");
        return;
    }

    NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:@"http://myhost.com/filecreate.php?token=%@",[[NSUserDefaults standardUserDefaults] objectForKey:@"apnsToken"]]]; //set here your URL

    NSURLRequest *urlRequest = [NSURLRequest requestWithURL:url];
    NSOperationQueue *queue = [[NSOperationQueue alloc] init];

    [NSURLConnection sendAsynchronousRequest:urlRequest queue:queue completionHandler:^(NSURLResponse *response, NSData *data, NSError *error)
     {
         if (error == nil) {
             [[NSUserDefaults standardUserDefaults] setBool:YES forKey:@"apnsTokenSentSuccessfully"];
             NSLog(@"Token is being sent successfully");
             //you can check server response here if you need
         }
     }];
}

@end

Then you can call [DataUpdater sendUserToken]; in your controllers when internet connection appears, or periodically, or in -(void)viewDidLoad or -(void)viewWillAppear methods

My advises:
1) I use AFNetworking to send async request and check server JSON response
2) Some times it's better to use services such as Parse to work with push notifications