@getkist/action-terser

JavaScript minification with Terser.

Installation

npm install --save-dev @getkist/action-terser

Actions

JavaScriptMinifyAction

Minifies JavaScript files using Terser.

Options

Option	Type	Default	Description
inputFile	string	Required	Path to input JS file
outputFile	string	Required	Path to output file
sourceMap	boolean	false	Generate source maps
mangle	boolean	true	Mangle variable names
compress	boolean|object	true	Compression options
format	object	-	Output format options

Basic Usage

plugins:
  - @getkist/action-terser

pipeline:
  build:
    stages:
      - name: minify
        steps:
          - action: JavaScriptMinifyAction
            options:
              inputFile: dist/js/bundle.js
              outputFile: dist/js/bundle.min.js

With Source Maps

- action: JavaScriptMinifyAction
  options:
    inputFile: dist/js/bundle.js
    outputFile: dist/js/bundle.min.js
    sourceMap: true

Custom Compression

- action: JavaScriptMinifyAction
  options:
    inputFile: dist/js/bundle.js
    outputFile: dist/js/bundle.min.js
    compress:
      drop_console: true
      drop_debugger: true
      pure_funcs:
        - console.log
        - console.debug

After TypeScript Compilation

Common workflow: compile then minify:

plugins:
  - @getkist/action-typescript
  - @getkist/action-terser

pipeline:
  build:
    stages:
      - name: compile
        steps:
          - action: TypeScriptCompilerAction
            options:
              tsconfig: tsconfig.json
              outDir: dist/js
              
      - name: minify
        steps:
          - action: JavaScriptMinifyAction
            options:
              inputFile: dist/js/index.js
              outputFile: dist/js/index.min.js
              sourceMap: true

Compression Options

Common compression options:

compress:
  # Remove console statements
  drop_console: true
  
  # Remove debugger statements
  drop_debugger: true
  
  # Inline simple functions
  inline: true
  
  # Remove dead code
  dead_code: true
  
  # Pass count for compression
  passes: 2

Output Format Options

Control output formatting:

format:
  # Preserve some comments
  comments: "some"
  
  # Use semicolons
  semicolons: true
  
  # Quote style
  quote_style: 3

Size Reduction

Typical size reduction with default settings:

Input	Output	Reduction
100 KB	~40 KB	60%
500 KB	~180 KB	64%
1 MB	~350 KB	65%

TIP

Enable gzip compression on your server for an additional 70-80% reduction when served.

Links

• npm
• GitHub
• Changelog