copy-webpack-plugin

copy-webpack-plugin

Copies individual files or entire directories, which already exist, to the build directory.

Getting Started

To begin, you'll need to install copy-webpack-plugin:

$ npm install copy-webpack-plugin --save-dev

Then add the plugin to your webpack config. For example:

webpack.config.js

const CopyPlugin = require('copy-webpack-plugin');

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        { from: 'source', to: 'dest' },
        { from: 'other', to: 'public' },
      ],
    }),
  ],
};

ℹ️ webpack-copy-plugin is not designed to copy files generated from the build process; rather, it is to copy files that already exist in the source tree, as part of the build process.

ℹ️ If you want webpack-dev-server to write files to the output directory during development, you can force it with the writeToDisk option or the write-file-webpack-plugin.

Options

The plugin's signature:

webpack.config.js

const CopyPlugin = require('copy-webpack-plugin');

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        { from: 'source', to: 'dest' },
        { from: 'other', to: 'public' },
      ],
      options: {
        concurrency: 100,
      },
    }),
  ],
};

Patterns

Name	Type	Default	Description
from	{String}	undefined	Glob or path from where we сopy files.
to	{String}	compiler.options.output	Output path.
context	{String}	options.context || compiler.options.context	A path that determines how to interpret the from path.
globOptions	{Object}	undefined	Options passed to the glob pattern matching library including ignore option.
toType	{String}	undefined	Determinate what is to option - directory, file or template.
force	{Boolean}	false	Overwrites files already in compilation.assets (usually added by other plugins/loaders).
flatten	{Boolean}	false	Removes all directory references and only copies file names.
transform	{Function}	undefined	Allows to modify the file contents.
cacheTransform	{Boolean|String|Object}	false	Enable transform caching. You can use { cache: { key: 'my-cache-key' } } to invalidate the cache.
transformPath	{Function}	undefined	Allows to modify the writing path.
noErrorOnMissing	{Boolean}	false	Doesn't generate an error on missing file(s).

from

Type: String Default: undefined

Glob or path from where we сopy files. Globs accept fast-glob pattern-syntax. Glob can only be a string.

⚠️ Don't use directly \\ in from option if it is a glob (i.e path\to\file.ext) option because on UNIX the backslash is a valid character inside a path component, i.e., it's not a separator. On Windows, the forward slash and the backward slash are both separators. Instead please use /.

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        'relative/path/to/file.ext',
        'relative/path/to/dir',
        path.resolve(__dirname, 'src', 'file.ext'),
        path.resolve(__dirname, 'src', 'dir'),
        '**/*',
        {
          from: '**/*',
        },
        // If absolute path is a `glob` we replace backslashes with forward slashes, because only forward slashes can be used in the `glob`
        path.posix.join(
          path.resolve(__dirname, 'src').replace(/\\/g, '/'),
          '*.txt'
        ),
      ],
    }),
  ],
};

For windows

If you define from as absolute file path or absolute folder path on Windows, you can use windows path segment (\\)

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: path.resolve(__dirname, 'file.txt'),
        },
      ],
    }),
  ],
};

But you should always use forward-slashes in glob expressions See fast-glob manual.

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          // If absolute path is a `glob` we replace backslashes with forward slashes, because only forward slashes can be used in the `glob`
          from: path.posix.join(
            path.resolve(__dirname, 'fixtures').replace(/\\/g, '/'),
            '*.txt'
          ),
        },
      ],
    }),
  ],
};

The context behaves differently depending on what the from is (glob, file or dir). More examples

to

Type: String Default: compiler.options.output

Output path.

⚠️ Don't use directly \\ in to (i.e path\to\dest) option because on UNIX the backslash is a valid character inside a path component, i.e., it's not a separator. On Windows, the forward slash and the backward slash are both separators. Instead please use / or path methods.

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: '**/*',
          to: 'relative/path/to/dest/',
        },
        {
          from: '**/*',
          to: '/absolute/path/to/dest/',
        },
        {
          from: '**/*',
          to: '[path][name].[contenthash].[ext]',
        },
      ],
    }),
  ],
};

context

Type: String Default: options.context|compiler.options.context

A path that determines how to interpret the from path.

⚠️ Don't use directly \\ in context (i.e path\to\context) option because on UNIX the backslash is a valid character inside a path component, i.e., it's not a separator. On Windows, the forward slash and the backward slash are both separators. Instead please use / or path methods.

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: 'src/*.txt',
          to: 'dest/',
          context: 'app/',
        },
      ],
    }),
  ],
};

The context option can be an absolute or relative path. If context is a relative, then it is converted to absolute based to compiler.options.context

Also, context indicates how to interpret the search results. Further, he is considered in this role.

To determine the structure from which the found resources will be copied to the destination folder, the context option is used.

If from is a file, then context is equal to the directory in which this file is located. Accordingly, the result will be only the file name.

If from is a directory, then context is the same as from and is equal to the directory itself. In this case, the result will be a hierarchical structure of the found folders and files relative to the specified directory.

If from is a glob, then regardless of the context option, the result will be the structure specified in the from option

More examples

globOptions

Type: Object Default: undefined

Allows to configute the glob pattern matching library used by the plugin. See the list of supported options To exclude files from the selection, you should use globOptions.ignore option

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: 'public/**/*',
          globOptions: {
            dot: true,
            gitignore: true,
            ignore: ['**/file.*', '**/ignored-directory/**'],
          },
        },
      ],
    }),
  ],
};

toType

Type: String Default: undefined

Determinate what is to option - directory, file or template. Sometimes it is hard to say what is to, example path/to/dir-with.ext. If you want to copy files in directory you need use dir option. We try to automatically determine the type so you most likely do not need this option.

Name	Type	Default	Description
'dir'	{String}	undefined	If to has no extension or ends on '/'
'file'	{String}	undefined	If to is not a directory and is not a template
'template'	{String}	undefined	If to contains a template pattern

'dir'

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: 'path/to/file.txt',
          to: 'directory/with/extension.ext',
          toType: 'dir',
        },
      ],
    }),
  ],
};

'file'

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: 'path/to/file.txt',
          to: 'file/without/extension',
          toType: 'file',
        },
      ],
    }),
  ],
};

'template'

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: 'src/',
          to: 'dest/[name].[hash].[ext]',
          toType: 'template',
        },
      ],
    }),
  ],
};

force

Type: Boolean Default: false

Overwrites files already in compilation.assets (usually added by other plugins/loaders).

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: 'src/**/*',
          to: 'dest/',
          force: true,
        },
      ],
    }),
  ],
};

flatten

Type: Boolean Default: false

Removes all directory references and only copies file names.

⚠️ If files have the same name, the result is non-deterministic.

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: 'src/**/*',
          to: 'dest/',
          flatten: true,
        },
      ],
    }),
  ],
};

transform

Type: Function Default: undefined

Allows to modify the file contents.

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: 'src/*.png',
          to: 'dest/',
          // The `content` argument is a [`Buffer`](https://nodejs.org/api/buffer.html) object, it could be converted to a `String` to be processed using `content.toString()`
          // The `absoluteFrom` argument is a `String`, it is absolute path from where the file is being copied
          transform(content, absoluteFrom) {
            return optimize(content);
          },
        },
      ],
    }),
  ],
};

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: 'src/*.png',
          to: 'dest/',
          transform(content, path) {
            return Promise.resolve(optimize(content));
          },
        },
      ],
    }),
  ],
};

cacheTransform

Type: Boolean|String|Object Default: false

Enable/disable and configure caching. Default path to cache directory: node_modules/.cache/copy-webpack-plugin.

Boolean

Enables/Disable transform caching.

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: 'src/*.png',
          to: 'dest/',
          transform(content, path) {
            return optimize(content);
          },
          cacheTransform: true,
        },
      ],
    }),
  ],
};

String

Enables transform caching and setup cache directory.

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: 'src/*.png',
          to: 'dest/',
          transform(content, path) {
            return optimize(content);
          },
          // Should be absolute
          cacheTransform: path.resolve(__dirname, 'cache-directory'),
        },
      ],
    }),
  ],
};

Object

Enables transform caching and setup cache directory and invalidation keys.

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: 'src/*.png',
          to: 'dest/',
          transform(content, path) {
            return optimize(content);
          },
          cacheTransform: {
            directory: path.resolve(__dirname, 'cache-directory'),
            keys: {
              // May be useful for invalidating cache based on external values
              // For example, you can invalid cache based on `process.version` - { node: process.version }
              key: 'value',
            },
          },
        },
      ],
    }),
  ],
};

You can setup invalidation keys using a function.

Simple function:

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: 'src/*.png',
          to: 'dest/',
          transform(content, path) {
            return optimize(content);
          },
          cacheTransform: {
            directory: path.resolve(__dirname, 'cache-directory'),
            keys: (defaultCacheKeys, absoluteFrom) => {
              const keys = getCustomCacheInvalidationKeysSync();

              return {
                ...defaultCacheKeys,
                keys,
              };
            },
          },
        },
      ],
    }),
  ],
};

Async function:

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: 'src/*.png',
          to: 'dest/',
          transform(content, path) {
            return optimize(content);
          },
          cacheTransform: {
            directory: path.resolve(__dirname, 'cache-directory'),
            keys: async (defaultCacheKeys, absoluteFrom) => {
              const keys = await getCustomCacheInvalidationKeysAsync();

              return {
                ...defaultCacheKeys,
                keys,
              };
            },
          },
        },
      ],
    }),
  ],
};

transformPath

Type: Function Default: undefined

Allows to modify the writing path.

⚠️ Don't return directly \\ in transformPath (i.e path\to\newFile) option because on UNIX the backslash is a valid character inside a path component, i.e., it's not a separator. On Windows, the forward slash and the backward slash are both separators. Instead please use / or path methods.

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: 'src/*.png',
          to: 'dest/',
          transformPath(targetPath, absolutePath) {
            return 'newPath';
          },
        },
      ],
    }),
  ],
};

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: 'src/*.png',
          to: 'dest/',
          transformPath(targetPath, absolutePath) {
            return Promise.resolve('newPath');
          },
        },
      ],
    }),
  ],
};

noErrorOnMissing

Type: Boolean Default: false

Doesn't generate an error on missing file(s);

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: path.resolve(__dirname, 'missing-file.txt'),
          noErrorOnMissing: true,
        },
      ],
    }),
  ],
};

Options

Name	Type	Default	Description
concurrency	{Number}	100	Limits the number of simultaneous requests to fs

concurrency

limits the number of simultaneous requests to fs

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [...patterns],
      options: { concurrency: 50 },
    }),
  ],
};

Examples

Different variants from (glob, file or dir).

Take for example the following file structure:

src/directory-nested/deep-nested/deepnested-file.txt
src/directory-nested/nested-file.txt

From is a Glob

Everything that you specify in from will be included in the result:

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: 'src/directory-nested/**/*',
        },
      ],
    }),
  ],
};

Result:

src/directory-nested/deep-nested/deepnested-file.txt,
src/directory-nested/nested-file.txt

If you want only content src/directory-nested/, you should only indicate glob in from. The path to the folder in which the search should take place, should be moved to context.

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: '**/*',
          context: path.resolve(__dirname, 'src', 'directory-nested'),
        },
      ],
    }),
  ],
};

Result:

deep-nested/deepnested-file.txt,
nested-file.txt

From is a Dir

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: path.resolve(__dirname, 'src', 'directory-nested'),
        },
      ],
    }),
  ],
};

Result:

deep-nested/deepnested-file.txt,
nested-file.txt

Technically, this is **/* with a predefined context equal to the specified directory.

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: '**/*',
          context: path.resolve(__dirname, 'src', 'directory-nested'),
        },
      ],
    }),
  ],
};

Result:

deep-nested/deepnested-file.txt,
nested-file.txt

From is a File

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: path.resolve(
            __dirname,
            'src',
            'directory-nested',
            'nested-file.txt'
          ),
        },
      ],
    }),
  ],
};

Result:

nested-file.txt

Technically, this is a filename with a predefined context equal to path.dirname(pathToFile).

webpack.config.js

module.exports = {
  plugins: [
    new CopyPlugin({
      patterns: [
        {
          from: 'nested-file.txt',
          context: path.resolve(__dirname, 'src', 'directory-nested'),
        },
      ],
    }),
  ],
};

Result:

nested-file.txt

Contributing

Please take a moment to read our contributing guidelines if you haven't yet done so.

CONTRIBUTING

License

MIT