Sending nRFCloud CoAP while network not available

RE: Sending nRFCloud CoAP while network not available

Sigurd — Thu, 30 May 2024 08:20:07 GMT

[quote user="Vincent44"]Do you have an approximate release date for v2.7.0? Are we talking days, week, months ?[/quote]

~End of June timeframe

RE: Sending nRFCloud CoAP while network not available

Vincent44 — Thu, 30 May 2024 06:21:50 GMT

Hello Sigurd,

Thanks for your reply.

Do you have an approximate release date for v2.7.0? Are we talking days, week, months ?

RE: Sending nRFCloud CoAP while network not available

Sigurd — Wed, 29 May 2024 17:53:36 GMT

Hi,

I got some input from the developers on this issue. We are aware of the issue; we have many improvements about to merge to NCS to improve reliability, including the abililty to detect and recover from network outages. These improvments will be part of the upcoming NCS v2.7.0

RE: Sending nRFCloud CoAP while network not available

Vincent44 — Tue, 21 May 2024 13:59:07 GMT

So, I tried adding a timer in order to stop the process in case it is stuck.

The idea is to be able to pause/stop the sending, resulting in nrf_cloud_coap_json_message_send() to return an error code.

The code looks like this:

struct k_timer preventBeingStuckTimer ;
void preventBeingStuck_TimerCallback( struct k_timer * a)
{	
	nrf_cloud_coap_pause() ;
	k_timer_stop(&preventBeingStuckTimer) ;
}


bool COAP_Send(char * msg, uint16_t msgLen)
{	
	bool success ;
	int err ;	

	k_timer_start(&preventBeingStuckTimer, Z_TIMEOUT_MS(5000), Z_FOREVER ) ;

	err = nrf_cloud_coap_json_message_send(msg) ;

	if(err == 0){
		success = true ;
	}
	else
	{
		// Negative values are device-side errors defined in errno.h.
		// Positive values are cloud-side errors (CoAP result codes) defined in zephyr/net/coap.h. 
		if(err < 0){
			DEBUG_PRINT("Error while sending (Device err: %d) !\r\n", err) ;
		}else{
			DEBUG_PRINT("Error while sending (Cloud err: %d) !\r\n", err) ;
		}
		success = false ;
	}

	k_timer_stop(&preventBeingStuckTimer) ;
	
	return success ;
}

The timer triggers, but the execution hangs at nrf_cloud_coap_pause().

My guess is that the nrfcloud_coap operations can't be pause in case it is currently trying to send/receive data.

I also tried nrf_cloud_coap_disconnect(), which I expected to be more brutal ... but I got the same results.

During my test, I also had similar issue with nRFCloud FOTA functions. I am not 100% sure that it was the exact same issue, as I was not in debug mode, but I noticed some watchdog reboot while my device was checking for FOTA nrf_cloud_rest_fota_job_get() at location where network quality was low.

How can I do to abort the process once it has been started ?

As an extra safety, I can check that the device is still connected to the network before sending data. However, this won't cover all cases, as disconnect can occur anytime.

RE: Sending nRFCloud CoAP while network not available

Vincent44 — Tue, 16 Apr 2024 08:37:19 GMT

This still requires having a timer/WDT to detect that nrf_cloud_coap_json_message_send() is stuck.

I guess it also implies using different threads.

Being able to hand a timeout as parameter to nrf_cloud_coap_json_message_send() would be a nive feature.

RE: Sending nRFCloud CoAP while network not available

Sigurd — Fri, 12 Apr 2024 14:29:33 GMT

[quote user="Vincent44"]Concerning the WDT, it might be due to the fact I used the WDT_OPT_PAUSE_IN_SLEEP option.When I remove it, the watchdog does indeed reboots the device when it's hanging at nrf_cloud_coap_json_message_send() with no network.[/quote]

Yes, that would explain it. Regarding abort the sending, then maybe you could try nrf_cloud_coap_pause().

RE: Sending nRFCloud CoAP while network not available

Vincent44 — Thu, 11 Apr 2024 08:02:03 GMT

Concerning the WDT, it might be due to the fact I used the WDT_OPT_PAUSE_IN_SLEEP option.When I remove it, the watchdog does indeed reboots the device when it's hanging at nrf_cloud_coap_json_message_send() with no network.