Use Curl to fetch HTML file 
Curl syntax to fetch HTML file

  curl https://xfido.com > /tmp/x.html
Use Curl to post JSON 
 curl -X POST http://localhost:8081/insertcode -H 'Content-Type: application/json' -d 
     '{"pid":0, "newcode":"tt444:*: tt4\n test1 test2\n test3 test4\n", "begt":0, "endt":0}'