extract_key — pull a single key from any JSON-producing command via jq. Generic zsh utility.

extract_key.zsh

#!/usr/bin/env zsh
# extract_key — pull a single key from a JSON-producing command
#
# Generic pattern: run any command that outputs JSON, extract one key via jq.
# The last argument is always the key; everything before it becomes the command arguments.
#
# Usage:
#   extract_key <command> [args...] <json_key>
#
# Examples:
#   # Extract "status" from a ticket viewer
#   extract_key jira-status NA-393 status
#
#   # Extract "email" from a user lookup
#   extract_key gh api users/octocat email
#
#   # Works with any command that outputs a JSON object
#   extract_key curl -s https://api.example.com/item/42 name
#
# Requires: jq

function extract_key() {
    if (( $# < 2 )); then
        print -u2 'Usage: extract_key <command> [args...] <key>'
        return 1
    fi

    local key=$argv[-1]                     # last word is the key
    local cmd=("${(@)argv[1,-2]}")          # everything else is the command

    "${cmd[@]}" | jq -r --arg key "$key" '.[$key]'
}

# If sourced, the function is available. If executed directly, run it.
if [[ "${(%):-%N}" == "$0" ]]; then
    extract_key "$@"
fi