gem-hunter

A Rollup plugin that displays output bundle sizes.

This project was inspired by rollup-plugin-bundle-size.

npm install --save-dev rollup-plugin-output-size

// ESM
import outputSize from 'rollup-plugin-output-size';

// CommonJS
const { outputSize } = require('rollup-plugin-output-size');

Use the plugin, example rollup.config.js:

import outputSize from 'rollup-plugin-output-size';

export default {
  input: 'index.js',
  output: { dir: 'dist' },
  plugins: [outputSize(/* plugin options */)]
};

You can change and override the behavior of this plugin through its options. Note that all options are optional.

Type: boolean
Default: false

Displays the size in bytes for both the output info and summary output (e.g. 4,096 B instead of 4.1 kB).

Type: boolean | OutputType[]
Default: false

Disables output types display.

Set to true to disable output for all output types, or set an array to specify which output types will not be displayed.

Output types are: asset, chunk, and entry.

Both chunk and entry output types are OutputChunks but entry chunks have isEntry values of true.

This option does not affect the summary output.

Type: boolean | OutputType[]
Default: true

Gets gzipped sizes of output.

Set to false to skip getting gzipped size, or set an array to only get gzipped sizes of specified output types.

Type: boolean
Default: false

Disables output. This will also skip the handle and summary callbacks.

Type: boolean | 'always' | SummaryCallback
Default: true

Displays the summary output.

• Set to false to disable summary output.
• Set to 'always' to force summary output even if there is only one (1) output.
• Set a callback to override default summary output.

See types in summary.types.ts.

Type: (info: OutputInfo, output: OutputAsset | OutputChunk) => void | Promise<void>

Overrides the default logging of output info.

The second argument output is the current Rollup output asset or chunk to log, while the first argument is the OutputInfo.

See types in output.types.ts.

This package also includes some utility functions that you may find helpful, especially when making use of the handle and summary options.

Type: (info: OutputInfo, options?: Pick<Options, "bytes">) => string

Gets the default display format of output info.

import outputSize, { format } from 'rollup-plugin-output-size';

export default {
  input: 'index.js',
  output: { dir: 'dist' },
  plugins: [
    outputSize({
      handle(info) {
        console.log(format(info));
      }
    })
  ]
};

[{type}] {path} is {hSize} → {gzip.hSize} (gzip)

Type: (input: string | Uint8Array) => Promise<Size>

Gets the gzipped size of input.

import outputSize, { gzip } from 'rollup-plugin-output-size';

export default {
  input: 'index.js',
  output: { dir: 'dist' },
  plugins: [
    outputSize({
      gzip: false,
      async handle(info, output) {
        const data = output.type === 'chunk' ? output.code : output.source;
        const gzipInfo = await gzip(data);
        console.log(info.path, gzipInfo);
      }
    })
  ]
};

Type: (summary: Summary, options?: Pick<Options, "bytes">) => string

Gets the default display format of summary info.

import outputSize, { summarize } from 'rollup-plugin-output-size';

export default {
  input: 'index.js',
  output: { dir: 'dist' },
  plugins: [
    outputSize({
      summary(summary) {
        console.log(summarize(summary));
      }
    })
  ]
};

[total] {entry.hSize} + {chunk.hSize} + {asset.hSize} = {total.hSize}
[total] {gzip.entry.hSize} + {gzip.chunk.hSize} + {gzip.asset.hSize} = {gzip.total.hSize} (gzip)

Licensed under the MIT License.