MHSNTP – SNTP pod

This is a pod for easy SNTP client support in macOS, iOS and tvOS. It's main goals are:

• RFC 4330 compliance.
• As much covered by unit tests as possible.
• Modern Objective-C syntax for good support of both Objective-C and Swift.

This pod does not alter the system's clock. It merely provides easy access to networked time for your apps.

Current limitations

• Only unicast operation is supported at the moment.

Dependencies

This pod requires CocoaAsyncSocket to handle the UDP communication.

Integration in your project

This project is available as a CocoaPod, so you simply need to add the following line to your Podfile:

pod 'MHSNTP'

There are two ways to integrate this pod: as module or not. To integrate using modules, add use_frameworks! to your Podfile. After this, you reference the pod like this:

// Objective-C
@import MHSNTP;

// Swift
import MHSNTP

If you are not using modules, you need to import the umbrella header in Objective-C:

#import <MHSNTP/MHSNTP.h>

When using the pod in Swift without modules, you need add #import <MHSNTP/MHSNTP.h> to your bridging header. No import MHSNTP is needed in this case.

Usage

The most simple way to use this pod is to instantiate a MHSNTPManager instance and add Apple's NTP servers (there's a convenience method for that).

Objective-C example:

// Store the instance in a property or global variable to keep it alive.
MHSNTPManager * sntp = [[MHSNTPManager alloc] init];
[sntp addAppleSNTPServers];

// After adding the servers, the manager automatically starts querying them.
// You can then fetch the corrected current time via:
NSDate * now = [sntp now];

// Or you can query the offset of the local clock for other time calculations:
NSTimeInterval offset = [sntp systemClockOffset];

Swift example:

let sntp = MHSNTPManager()
sntp.addAppleSNTPServers()

let now = sntp.now()
let offset = sntp.systemClockOffset()

Please note that querying the servers for the first time is not instantaneous. So you may want to instantiate the manager as early as possible/necessary in your app's lifecycle so you hopefully have received responses by the time you actually need to use the network time.