skill-3（技能 3）

JSON Toolkit

A zero-dependency Python utility for working with JSON data. Validates, formats, minifies, queries, and inspects JSON files — all with Python's standard library.

Features

• Pretty-print with configurable indentation (2, 4, or any number of spaces)
• Minify JSON to reduce file size for APIs and storage
• Validate JSON and get structural stats (type, key count, size)
• Query nested data with dot-notation paths including array indices
• Sort keys alphabetically for deterministic output and easier diffs
• Stdin support for use in shell pipelines with other tools

Usage Examples

Pretty-print a JSON file:

python main.py data.json

Validate without output:

python main.py config.json --validate
# ✓ Valid JSON
#   Type: object (12 keys)
#   Size: 4832 bytes

Query a nested value:

python main.py users.json --query data.users.0.name
# "Alice"

Minify for production:

python main.py config.json --minify -o config.min.json

Sort keys for consistent diffs:

python main.py package.json --sort-keys -o package-sorted.json

Pipe from curl:

curl -s https://api.example.com/data | python main.py - --query results.0

Query Syntax

Use dot notation to navigate nested structures. Array indices are numbers:

• name — top-level key
• data.users — nested object key
• data.users.0 — first element of an array
• data.users.0.email — field of the first array element
• config.servers.2.host — deeply nested value

Command Line Options

• input — JSON file path, or - for stdin
• -o, --output — Output file (defaults to stdout)
• --indent N — Indentation spaces (default: 2)
• --minify — Output minified JSON (no whitespace)
• --query PATH / -q PATH — Extract a value at the given dot-notation path
• --validate — Only validate and print stats, no output
• --sort-keys — Sort object keys alphabetically
• --json — (implicit) Output is always valid JSON