json-extract-cli

Extract a nested JSON value using a dot-path

Install

npm install --global json-extract-cli

Usage

$ json-extract --help

  Usage
    $ json-extract <path> [options]

  Options
    --file <path>       Read from file instead of stdin
    --json              Pretty-print output as JSON
    --fallback <value>  Return fallback value if path not found
    --quiet             Suppress errors, exit 0 on failure

  Examples
    $ echo '{"user":{"email":"a@b.com"}}' | json-extract "user.email"
    a@b.com

    $ json-extract "user.name" --file data.json
    John

    $ json-extract "missing.path" --fallback "default"
    default

Examples

Extract from piped input

$ echo '{"user":{"name":"John","email":"john@example.com"}}' | json-extract "user.email"
john@example.com

Extract from file

$ json-extract "user.name" --file data.json
John

Extract nested arrays

$ echo '{"users":[{"name":"Alice"},{"name":"Bob"}]}' | json-extract "users"
[{"name":"Alice"},{"name":"Bob"}]

Pretty-print output

$ echo '{"users":[{"name":"Alice"}]}' | json-extract "users" --json
[
  {
    "name": "Alice"
  }
]

Use fallback value

$ echo '{"user":{"name":"John"}}' | json-extract "user.age" --fallback "unknown"
unknown

Quiet mode (suppress errors)

$ echo '{"user":{"name":"John"}}' | json-extract "user.age" --quiet
$ echo $?
0

API

The tool accepts JSON input from stdin or a file and extracts values using dot-notation paths.

Supported types

• Strings
• Numbers
• Booleans
• null
• Arrays (returns full array as JSON)
• Objects (returns full object as JSON)

Path notation

Use dot-notation to access nested properties:

• user.name
• data.items.0.id
• config.settings.display.theme

Related

• jq - More powerful JSON processor
• fx - Interactive JSON viewer
• json - JSON manipulation tool

License

MIT