headson

Budget‑constrained JSON preview for the terminal.

Install

Using Cargo:

cargo install headson

From source:

cargo build --release
target/release/headson --help

Usage

headson [FLAGS] [INPUT]

• INPUT (optional): file path. If omitted, reads JSON from stdin.
• Prints the preview to stdout. On parse errors, exits non‑zero and prints an error to stderr.

Common flags:

• -n, --budget <BYTES>: output byte budget (default: 500)
• -f, --template <json|pseudo|js>: output style (default: pseudo)
• -m, --compact: no indentation, no spaces, no newlines
• --no-newline: single line output
• --no-space: no space after : in objects
• --indent <STR>: indentation unit (default: two spaces)
• --string-cap <N>: max graphemes to consider per string (default: 500)

Examples:

• Read from stdin with defaults:

  cat data.json | headson
  

• Read from file, JS style, 200‑byte budget:

  headson -n 200 -f js data.json
  

• JSON style, compact:

  headson -f json -m data.json
  

Show help:

headson --help