function::json_set_prefix - Linux


json_set_prefix is a versatile tool that provides an easy and efficient way to modify JSON data by setting the prefix for all keys within a specified JSON object. It’s particularly useful for tasks such as restructuring or organizing JSON data, and can be seamlessly integrated into various scripting or data processing workflows.


json_set_prefix [-c] [-e] [-i] [-f TEMPLATE] [-j FORMAT] [-l] [--strip-key] [-t] [-w] [-s] <prefix> <json_input> [<json_output>]


  • -c: Check for valid JSON input and output.
  • -e: Process JSON input and output as environment variables.
  • -f TEMPLATE: Specify a template string for key substitution. Use ${key} to replace the original key.
  • -i: Indent the JSON output for improved readability.
  • -j FORMAT: Specify the output format for the JSON output (e.g., compact, pretty).
  • -l: List all keys and values in the JSON object, prefixed with the specified prefix.
  • –strip-key: Remove the original key from the output JSON.
  • -s: Silently ignore errors and continue processing.
  • -t: Convert the input JSON to JSON text (i.e., enclose in quotes).
  • -w: Wrap the output in an array.


1. Setting Prefix for All Keys:

json_set_prefix "new_prefix_" '{ "key1": "value1", "key2": "value2" }'


{ "new_prefix_key1": "value1", "new_prefix_key2": "value2" }

2. Using Template for Key Substitution:

json_set_prefix -f "${prefix}_${key}" '{ "key1": "value1", "key2": "value2" }'


{ "prefix_key1": "value1", "prefix_key2": "value2" }

3. Listing Keys with Prefix:

json_set_prefix -l my_prefix '{ "key1": "value1", "key2": "value2" }'


my_prefix_key1: value1
my_prefix_key2: value2

4. Removing Original Keys:

json_set_prefix my_key -s '{ "key1": "value1", "my_key": "my_value" }'


{ "my_key": "my_value" }

Common Issues

  • Invalid JSON Input/Output: Ensure your JSON data is valid and properly formatted. Use the -c option to check for any errors.
  • Conflicting Prefix: If the specified prefix already exists in the JSON object, it will be overwritten.


json_set_prefix can be easily chained with other Linux commands for advanced processing tasks. For instance:

cat json_data.json | json_set_prefix my_prefix | jq '.my_prefix_key1'

Related Commands

  • jq: A powerful command-line tool for manipulating JSON data.
  • json_pp: A utility for pretty printing and minifying JSON data.