Format date time using jq

I have a bash (sh) script that makes several API calls and returns string values. One of them is a 'created_at' attribute of the JSON object returned.

released_at=$(echo -E "${json_response}" | jq -r '.[0].released_at'")

Value returned in ISO 8601 format: "released_at": "2023-09-27T17:36:07.182Z"

I would like it to be displayed as Wednesday, September 27, 2023

What would be the shortest way to achieve that?

Thanks!

Solution

jq provides access to your local operating system's strftime and strptime functions. (Note that one needs to be careful about portability when using these: Some libc implementations provide more operators than POSIX guarantees).

jq '
  .[0].released_at |                # extract field
  split(".")[0] |                  # strip seconds (not portably parsable)
  strptime("%Y-%m-%dT%H:%M:%S") |  # parse with strptime
  strftime("%A, %B, %Y")           # format with strftime
' <<'EOF'
[
  {"released_at": "2023-09-27T17:36:07.182Z"}
]
EOF

...emits as output:

"Wednesday, September, 2023"