Editing Gist with cURL: "Problems parsing JSON", - bash

Question

#!/bin/bash
curl -v \
--request PATCH \
--data "$(
printf '{"files": {"somefile.json": {"content": " {"field": "value"} "}}}' \
)" \
--user x:x \
https://api.github.com/gists/x
Tried adding --header "Content-Type: application/json", no luck.
I'm using this because the content is actually a command output but right now I'm testing the basics because this is not workig.
I believe is somethig related to double quote escaping in bash, tried for a couple of hours with no luck. This is a nightmare.
Any tip is welcomed. Thanks.

Answer 1

It looks like you have too many quotation marks. If you want the value of the "content" element to be an object, then instead of this:
"content": " {"field": "value"} "
try this:
"content": {"field": "value"}
On the off chance that you want it to be a string, then try this:
"content": " {\"field\": \"value\"} "

Answer 2

Instead of fighting against quote escaping, you could write your payload to a file and tell curl to use that file as data like so:
curl -v \
--request PATCH \
--data #/tmp/some/file \
--user x:x \
https://api.github.com/gists/x
Note the # sign in the --data argument, which tells curl that the rest of the argument is a file name to read data from.
Depending on how you create your payload, you could also pipe it to curl using - as filename (echo payload | curl --data #- ...)