This is a list of plugins which are used by webpack internally.
You should only care about them if you are building your own compiler based on webpack, or introspect the internals.
Categories of internal plugins:
Plugins affecting the environment of the compiler.
node/NodeEnvironmentPlugin()
Applies Node.js style filesystem to the compiler.
Plugins affecting the compiler
CachePlugin([cache])
Adds a cache to the compiler, where modules are cached.
You can pass a cache
object, where the modules are cached. Otherwise one is created per plugin instance.
ProgressPlugin(handler)
Hook into the compiler to extract progress information. The handler
must have the signature function(percentage, message)
. Percentage is called with a value between 0 and 1, where 0 indicates the start and 1 the end.
RecordIdsPlugin()
Saves and restores module and chunk ids from records.
Plugins, which add entry chunks to the compilation.
SingleEntryPlugin(context, request, chunkName)
Adds an entry chunk on compilation. The chunk is named chunkName
and contains only one module (plus dependencies). The module is resolved from request
in context
(absolute path).
MultiEntryPlugin(context, requests, chunkName)
Adds an entry chunk on compilation. The chunk is named chunkName
and contains a module for each item in the requests
array (plus dependencies). Each item in requests
is resolved in context
(absolute path).
PrefetchPlugin(context, request)
Prefetches request
and dependencies to enable a more parallel compilation. It doesn't create any chunk. The module is resolved from request
in context
(absolute path).
FunctionModulePlugin(context, options)
Each emitted module is wrapped in a function.
options
are the output options.
If options.pathinfo
is set, each module function is annotated with a comment containing the module identifier shortened to context
(absolute path).
JsonpTemplatePlugin(options)
Chunks are wrapped into JSONP-calls. A loading algorithm is included in entry chunks. It loads chunks by adding a <script>
tag.
options
are the output options.
options.jsonpFunction
is the JSONP function.
options.publicPath
is used as path for loading the chunks.
options.chunkFilename
is the filename under that chunks are expected.
node/NodeTemplatePlugin(options)
Chunks are wrapped into Node.js modules exporting the bundled modules. The entry chunks loads chunks by requiring them.
options
are the output options.
options.chunkFilename
is the filename under that chunks are expected.
LibraryTemplatePlugin(name, target)
The entries chunks are decorated to form a library name
of type type
.
webworker/WebWorkerTemplatePlugin(options)
Chunks are loaded by importScripts
. Else it's similar to JsonpTemplatePlugin
.
options
are the output options.
Decorates the module template by wrapping each module in a eval
annotated with // @sourceURL
.
SourceMapDevToolPlugin(sourceMapFilename, sourceMappingURLComment, moduleFilenameTemplate, fallbackModuleFilenameTemplate)
Decorates the templates by generating a SourceMap for each chunk.
sourceMapFilename
the filename template of the SourceMap. [hash]
, [name]
, [id]
, [file]
and [filebase]
are replaced. If this argument is missing, the SourceMap will be inlined as DataUrl.
NoHotModuleReplacementPlugin()
Defines module.hot
as false
to remove hot module replacement code.
HotModuleReplacementPlugin(options)
Add support for hot module replacement. Decorates the templates to add runtime code. Adds module.hot
API.
options.hotUpdateChunkFilename
the filename for hot update chunks.
options.hotUpdateMainFilename
the filename for the hot update manifest.
options.hotUpdateFunction
JSON function name for the hot update.
Plugins affecting the source code of modules.
Make webpack_public_path, webpack_require, webpack_modules and webpack_chunk_load accessible. Ensures that require.valueOf
and require.onError
are not processed by other plugins.
Currently useless. Ensures compatibility with other module loaders.
Offers a pseudo console
if it is not available.
Tries to evaluate expressions in if (...)
statements and ternaries to replace them with true
/false
for further possible dead branch elimination using hooks fired by the parser.
There are multiple optimizations in production mode regarding dead branches:
webpack will try to evaluate conditional statements. If it succeeds then the dead branch is removed. webpack can't do constant folding unless the compiler knows it. For example:
import { calculateTax } from './tax';
const FOO = 1;
if (FOO === 0) {
// dead branch
calculateTax();
}
In the above example, webpack is unable to prune the branch, but Terser does. However, if FOO
is defined using DefinePlugin, webpack will succeed.
It is important to mention that import { calculateTax } from './tax';
will also get pruned because calculateTax()
call was in the dead branch and got eliminated.
ProvidePlugin(name, request)
If name
is used in a module it is filled by a module loaded by require(<request>)
.
NodeStuffPlugin(options, context)
Provide stuff that is normally available in Node.js modules.
It also ensures that module
is filled with some Node.js stuff if you use it.
Provide stuff that is normally available in require.js.
require[js].config
is removed. require.version
is 0.0.0
. requirejs.onError
is mapped to require.onError
.
node/NodeSourcePlugin(options)
This module adds stuff from Node.js that is not available in non Node.js environments.
It adds polyfills for process
, console
, Buffer
and global
if used. It also binds the built in Node.js replacement modules.
node/NodeTargetPlugin()
The plugins should be used if you run the bundle in a Node.js environment.
If ensures that native modules are loaded correctly even if bundled.
dependencies/AMDPlugin(options)
Provides AMD-style define
and require
to modules. Also bind require.amd
, define.amd
and webpack_amd_options## to the options
passed as parameter.
dependencies/CommonJsPlugin
Provides CommonJs-style require
to modules.
dependencies/LabeledModulesPlugin()
Provide labels require:
and exports:
to modules.
dependencies/RequireContextPlugin(modulesDirectories, extensions)
Provides require.context
. The parameter modulesDirectories
and extensions
are used to find alternative requests for files. It's useful to provide the same arrays as you provide to the resolver.
dependencies/RequireEnsurePlugin()
Provides require.ensure
.
dependencies/RequireIncludePlugin()
Provides require.include
.
DefinePlugin(definitions)
Define constants for identifier.
definitions
is an object.
optimize/LimitChunkCountPlugin(options)
Merge chunks limit chunk count is lower than options.maxChunks
.
The overhead for each chunks is provided by options.chunkOverhead
or defaults to 10000. Entry chunks sizes are multiplied by options.entryChunkMultiplicator
(or 10).
Chunks that reduce the total size the most are merged first. If multiple combinations are equal the minimal merged size wins.
optimize/MergeDuplicateChunksPlugin()
Chunks with the same modules are merged.
optimize/RemoveEmptyChunksPlugin()
Modules that are included in every parent chunk are removed from the chunk.
optimize/MinChunkSizePlugin(minChunkSize)
Merges chunks until each chunk has the minimum size of minChunkSize
.
optimize/FlagIncludedChunksPlugin()
Adds chunk ids of chunks which are included in the chunk. This eliminates unnecessary chunk loads.
optimize/OccurrenceOrderPlugin(preferEntry)
Order the modules and chunks by occurrence. This saves space, because often referenced modules and chunks get smaller ids.
preferEntry
If true, references in entry chunks have higher priority
optimize/DedupePlugin()
Deduplicates modules and adds runtime code.