Bread-compressor-cli NPM

Command line tool for compressing static resources with brotli and gzip.

Installation

npm install bread-compressor-cli -D

Usage

Call the tool with npx

npx bread-compressor dist

or insert a script in package.json

 "scripts": {
	"compress": "bread-compressor dist"
  },

and run it with npm

npm run compress

Ignores

The tool ignores by default files with the suffix .gz, .br, .zst, .zip, .png, .jpeg, .jpg, .woff and .woff2. You can disable this with the -n option and all files will be compressed.

bread-compressor -n dist

Glob

You can specify multiple paths in one call, the tool processes all files that match the globs.

Compress files in dist and www folder and subfolders.

bread-compressor dist www

These globs are shortcuts for dist/**/ and www/**/

Only compress .css, .js and .html files in the dist folder and subfolders.

bread-compressor "dist/**/*.css" "dist/**/*.js" "dist/**/*.html"

Compress files in dist folder and subfolder, except big.txt and files ending with .pdf

bread-compressor dist "!big.txt" "!*.pdf"

See the globby project site for more information about the supported glob patterns:
https://github.com/sindresorhus/globby

Algorithm

The tool compresses the files by default with gzip and brotli. You can set the -a option to specify which algorithm to use. The -a options expects a comma separated list of algorithms.

Compress with gzip only

bread-compressor -a gzip dist

Compress with brotli and zstandard

bread-compressor -a brotli,zstd dist

Statistics

The tool prints out a summary with the -s option.

bread-compressor -s dist

gzip                                                              
Number of Files  : 7                                              
Uncompressed     : 53,467 Bytes                                   
Compressed       : 11,799 Bytes                                   
Compression Ratio: 22.07%                                         
Compression Time : 4.341 s                                        
                                                                  
brotli                                                            
Number of Files  : 7                                              
Uncompressed     : 53,467 Bytes                                   
Compressed       : 9,830 Bytes                                    
Compression Ratio: 18.39%                                         
Compression Time : 0.562 s

Zopfli options

You can pass options to the underlying zopfli library.

bread-compressor --zopfli-numiterations=15 --zopfli-blocksplittinglast=true dist

See the project site of @gfx/zopfli for more information.

Brotli options

You can pass options to the underlying brotli library.

bread-compressor --brotli-mode=0 --brotli-quality=10 --brotli-lgwin=21 dist

See the project site of brotli for more information.

Zstandard options

You can pass options to the underlying zstd-wasm library.

bread-compressor --zstd-level=10 -a zstd dist

See the project site of zstd-wasm

Concurrent tasks

By default, two tasks will run concurrently. You can change this number with the -l option

Run 4 compression tasks concurrently.

bread-compressor -l 4 dist

Internals

This tool depends on @gfx/zopfli and node-zopfli-es for GZip compression, brotli for Brotli compression and zstd-wasm for Zstandard compression.

Other dependecies are commander for command line argument parsing, chalk for terminal output styling, globby for glob matching and promise-limit for limiting concurrent tasks.

Browser Support for Brotli

Current versions of the major browsers send br in the Accept-Encoding header when the request is sent over TLS

Support introduced in version ...

Edge 15
Firefox 44
Chrome 50
Safari 11

Browser Support for Zstandard

Chrome 123

https://caniuse.com/zstd

Server support

To take advantage of precompressed resources you need a server that is able to understand the Accept-Encoding header and serve files ending with .gz and .br accordingly.

Nginx

Nginx supports Gzip compressed files out of the box with the gzip_static directive.

Add this to a http, server or location section and Nginx will automatically search for files ending with .gz when the request contains an Accept-Encoding header with the value gzip.