My POST request goes like this in the cmd or bash.
curl -I -X POST –url http://ec2-3-15-138-43.us-east-2.compute.amazonaws.com:8080/predict -H 'Content-Type: application/json' -d '[{"x0":"0.042317","x1":"-3.3447210000000003","x2":"4.635124212161472","x3":"-0.5983959993003629","x4":"-
........ ","x99":"-4.3278872999999995"}]’
Warning: You can only select one HTTP request method! You asked for both POST Warning: (-d, --data) and HEAD (-I, --head).