nRF9160 DK HTTP POST to my Webserver

[Hoang]

Dear , 

I want to use LTE_M of nRF9160 DK to POST to my webserver

Do you have any suggestions?

Thanks, 

Regards

hng

[Vidar Berg]

Hi,

Please see my response here: https://devzone.nordicsemi.com/f/nordic-q-a/46094/how-to-make-http-post-no-libcurl 

Regards,

Vidar

[Hoang]

Thank Vidar,

I will try it 

Regards,

hng

[Hoang]

It works, just fixed a little bit: 

/******************************************"**************************************/
#define MAXLINE 4096
#define HTTP_HOST "142.xx.xx.192"  //my webserver
#define HTTP_PORT 80
#define HTTP_PATH "/"
#define TEST_STRING  "Hello from nRF9160 DK"

#define POST_TEMPLATE "POST %s? HTTP/1.1\r\n"\
		"Host: %s\r\n"\
		"Connection: keep-alive\r\n"\
	        "Content-type: application/x-www-form-urlencoded\r\n"\
		"Content-length: %d\r\n\r\n"\
		"%s"
/************************************************************************/
void app_http_post()
{  
	//int err; 
    struct sockaddr_in local_addr;
	struct addrinfo *res;

	local_addr.sin_family = AF_INET;
	local_addr.sin_port = htons(0);
	local_addr.sin_addr.s_addr = 0;

	      
	int err = getaddrinfo(HTTP_HOST, NULL, NULL, &res);

	printk("getaddrinfo err: %d\n\r", err);
	((struct sockaddr_in *)res->ai_addr)->sin_port = htons(HTTP_PORT);
        
        char send_buf[MAXLINE + 1];
	
	int send_data_len_post = snprintf(send_buf,
				         500, /*total length should not exceed MTU size*/
				         POST_TEMPLATE, HTTP_PATH,
				         HTTP_HOST, strlen(TEST_STRING),
				         TEST_STRING);

	printk("send err: %d\n\r", send_data_len_post);


	int client_fd = socket(AF_INET, SOCK_STREAM, 0);

	printk("client_fd: %d\n\r", client_fd);
	err = bind(client_fd, (struct sockaddr *)&local_addr,
		   sizeof(local_addr));
	printk("bind err: %d\n\r", err);
        // connect
	err = blocking_connect(client_fd, (struct sockaddr *)res->ai_addr,
			       sizeof(struct sockaddr_in));
	printk("connect err: %d\n\r", err);
       //send
    blocking_send(client_fd, send_buf, send_data_len_post, 0);
    k_sleep(1000);
       
	printk("\n\r HTTP POST Finished. \n\r");
	close(client_fd);

}

Thanks so much

Regards, 

hng

[Vidar Berg]

Thanks for sharing the solution here. 

[Hoang]

DearVidar Berg

I tried to run this http post in a loop

first, i will check the LTE_M signal "AT+CEREG?"

It returns:  

Checking LTE_M signal.............

+CEREG: 0,5,"765D","0110C303",7

OK

Found the LTE_M signal 
Closing socket

  find LTE_M signal........... 
Checking LTE_M signal.............

+CEREG: 0,5,"765D","0110C303",7

OK

Found the LTE_M signal 
Closing socket

  find LTE_M signal........... 
Checking LTE_M signal.............

+CEREG: 0,5,"765D","0110C303",7

OK

Found the LTE_M signal 
Closing socket

  find LTE_M signal........... 
Checking LTE_M signal.............

+CEREG: 0,5,"765D","0110C303",7

OK

Found the LTE_M signal 
Closing socket

  find LTE_M signal........... 
Checking LTE_M signal.............

+CEREG: 0,5,"765D","0110C303",7

OK

Found the LTE_M signal 
Closing socket

  find LTE_M signal........... 
Checking LTE_M signal.............

+CEREG: 0,5,"765D","0110C303",7

OK

Found the LTE_M signal 
Closing socket

  find LTE_M signal........... 
Checking LTE_M signal.............

+CEREG: 0,5,"765D","0110C303",7

OK

Found the LTE_M signal 
Closing socket

  find LTE_M signal........... 
Checking LTE_M signal.............

Closing socket

 Couldnt find LTE_M signal........... 
Checking LTE_M signal.............

Closing socket

 Couldnt find LTE_M signal........... 
Checking LTE_M signal.............

After 7times, "AT+CEREG?" return NOTHING!

Why is the problem, the buffer is full? or something wrong in my code? 

Plz help me. 

Thanks so much 

Regards, 

hng

[Vidar Berg]

I believe a bug in the BSD library causes this. I get the "no memory" error when call socket send in a loop without any delay in-between. I have reported this internally. A workaround, for now, is to add a delay between each post request. 

[Hoang]

Dear Vidar Berg

I had 2s delay between

How long should I add ?

Thanks for fast responds, 

Regards, 

hng