Python Usage

Beautify JavaScript and CSS from Python using the jsbeautifier and cssbeautifier packages.

The Python packages only beautify JavaScript and CSS. HTML beautification is not supported by the Python implementation. For HTML, use the Node.js library or CLI.

Installation

Install the packages you need from PyPI:

JavaScript

pip install jsbeautifier

JavaScript Beautifier

Basic Usage

import jsbeautifier

result = jsbeautifier.beautify('function foo(){return 1;}')
print(result)
# function foo() {
#     return 1;
# }

Beautify from a File

import jsbeautifier

result = jsbeautifier.beautify_file('path/to/file.js')
print(result)

Custom Options

Fetch the default options object, modify the attributes you need, then pass it to beautify:

import jsbeautifier

opts = jsbeautifier.default_options()
opts.indent_size = 2
opts.space_in_empty_paren = True

result = jsbeautifier.beautify('function foo(){return 1;}', opts)
print(result)
# function foo() {
#   return 1;
# }

CSS Beautifier

Basic Usage

import cssbeautifier

result = cssbeautifier.beautify('.foo{color:red;background:blue;}')
print(result)
# .foo {
#     color: red;
#     background: blue;
# }

Custom Options

import cssbeautifier

opts = cssbeautifier.default_options()
opts.indent_size = 2
opts.end_with_newline = True

result = cssbeautifier.beautify('.foo{color:red;}', opts)
print(result)

CLI from Python Install

Installing jsbeautifier also installs the js-beautify command-line script. Beautified output goes to stdout by default:

js-beautify file.js

Write the output to a file:

js-beautify file.js -o file.pretty.js

Overwrite the input file in-place:

js-beautify -r file.js

Options Reference

Option names are the same as CLI flags with hyphens replaced by underscores. For example, --indent-size 2 --space-in-empty-paren corresponds to:

opts.indent_size = 2
opts.space_in_empty_paren = True

Option	Default	Description
indent_size	4	Spaces per indentation level
indent_char	" "	Character used for indentation
indent_with_tabs	False	Use tabs instead of spaces
eol	"auto"	Line terminator character(s) (auto = detect from file, else \n)
end_with_newline	False	End output with a newline
preserve_newlines	True	Keep existing blank lines
max_preserve_newlines	10	Maximum blank lines to preserve
brace_style	"collapse"	Brace placement style
space_in_paren	False	Pad inside parens: f( a, b )
space_in_empty_paren	False	Space inside empty parens: f( )
jslint_happy	False	Enable jslint-stricter mode
wrap_line_length	0	Wrap lines longer than N characters
comma_first	False	Put commas at the start of lines