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Json Lexer - Parse Receive data
Posted: Tue Mar 23, 2021 8:19 pm
by seulater
Looking at the examples Json, I am still confused...
I am using websockets on port 22000. When the browser sends me a json formatted string I get the data just fine.
Now I would like to parse and pull that data out. How do i put my received data into a JsonInObject so i can then use JsonInObject.FindFullNameString() or other json functions?
Using NNDK 2.7.7, MOD5270B
Re: Json Lexer - Parse Receive data
Posted: Wed Mar 24, 2021 2:12 pm
by pbreed
So assume the data is all in a buffer pData
ParsedJsonDataSet pjs(pData,len);
or if the pData is null terminated...
ParsedJsonDataSet pjs(pData);
Then you can operate on pjs...
Re: Json Lexer - Parse Receive data
Posted: Wed Mar 24, 2021 5:47 pm
by seulater
Thank you for the help! Tried a few ways but keep getting Trap errors.
This is what I have thus far.
Code: Select all
if (FD_ISSET(ws_fd, &read_fds))
{
int len = read( ws_fd, rx_buffer, ETHER_BUFFER_SIZE );
printf("RX[%d]:%s\r\n",len,rx_buffer);
ParsedJsonDataSet pjs(rx_buffer,len);
iprintf("%s\r\n",pjs.FindElementAfterName("deviceIp"));
}
The Json I am receiving is good.
RX[369]:{"CurrentConfiguration":{"unit_name":"Unit_01 ","select_static_dynamic_Ip":"true","deviceIp":"192.168.000.023","netmask":"255.255.255.000","gateway":"192.168.000.001","dns":"000.000.000.000","remoteIP":"000.000.000.000","udp_port":21800,"current_password":"ThePassowrd","alarm":"0","codec":"1","hoot_holler":"3","mode2w4w":"1","txinterval":60,"rxinterval":200}}
But this throws a trap.
Basically I want to pull each ID's data out. I.E. If I want to get the data for netmask, how do i parse the json and pull that piece out of it?
Re: Json Lexer - Parse Receive data
Posted: Wed Mar 24, 2021 6:12 pm
by pbreed
How is rx_buffer declared?
Also this is not valid:
iprintf("%s\r\n",pjs.FindElementAfterName("deviceIp"));
pjs.FindElementAfterName returns a json_primative_type
IE an integer and your trying to print like a string?
I think you want:
iprintf("%s\r\n",pjs.FindString("deviceIp"));
or...functionally identical...
if(pjs.FindElementAfterName("deviceIp")==STRING)
{
printf("Found %s\r\n",pjs.CurrentString());
}
else
{
printf("Did not find string "deviceIp");
}
Re: Json Lexer - Parse Receive data
Posted: Wed Mar 24, 2021 6:18 pm
by seulater
I seem to be getting close to your answers, thank you. I finally took a look at the example
C:\nburn\examples\StandardStack\WebClient\EarthQuake.
char rx_buffer[ETHER_BUFFER_SIZE + 1];
Re: Json Lexer - Parse Receive data
Posted: Wed Mar 24, 2021 6:23 pm
by seulater
I got it the Json parsing now, thank you for your help Paul!