How can I use a variable in curl call within bash script

Question

I have this simple task and I\'ve spent a few hours already trying to figure out how can I use a variable inside a curl call within my bash script:

message=\         


        

Answer 1

While the other post (and shellcheck) correctly points out that single quotes prevent variable expansion, the robust solution is to use a JSON tool like jq:

message="Hello there"
curl -X POST -H 'Content-type: application/json' \
    --data "$(jq -n --arg var "$message"  '.text = $var')"

This works correctly even when $message contains quotes and backslashes, while just injecting it in a JSON string can cause data corruption, invalid JSON or security issues.