webpack --env prod
"prod"
For proper usage and easy distribution of this configuration, webpack can be configured with webpack.config.js
. Any parameters sent to the CLI will map to a corresponding parameter in the config file.
Read the installation guide if you don't already have webpack and CLI installed.
webpack [--config webpack.config.js]
See configuration for the options in the configuration file.
webpack <entry> [<entry>] -o <output>
<entry>
A filename or a set of named filenames which act as the entry point to build your project. You can pass multiple entries (every entry is loaded on startup). If you pass a pair in the form <name>=<request>
, you can create an additional entry point. It will be mapped to the configuration option entry
.
<output>
A path and filename for the bundled file to be saved in. It will be mapped to the configuration options output.path
and output.filename
.
Example
If your project structure is as follows -
.
├── dist
├── index.html
└── src
├── index.js
├── index2.js
└── others.js
webpack src/index.js -o dist/bundle.js
This will bundle your source code with entry as index.js
, and the output bundle file will have a path of dist
, and the filename will be bundle.js
| Asset | Size | Chunks | Chunk Names |
|-----------|---------|-------------|-------------|
| bundle.js | 1.54 kB | 0 [emitted] | index |
[0] ./src/index.js 51 bytes {0} [built]
[1] ./src/others.js 29 bytes {0} [built]
webpack index=./src/index.js entry2=./src/index2.js -o dist/bundle.js
This will form the bundle with both the files as separate entry points.
| Asset | Size | Chunks | Chunk Names |
|-----------|---------|---------------|---------------|
| bundle.js | 1.55 kB | 0,1 [emitted] | index, entry2 |
[0] ./src/index.js 51 bytes {0} [built]
[0] ./src/index2.js 54 bytes {1} [built]
[1] ./src/others.js 29 bytes {0} {1} [built]
Note that Command Line Interface has a higher precedence for the arguments you use it with than your configuration file. For instance, if you pass
--mode="production"
to webpack CLI and your configuration file usesdevelopment
,production
will be used.
List all of the options available on the cli
webpack --help
webpack -h
Build source using a config file
Specifies a different configuration file to pick up. Use this if you want to specify something different from webpack.config.js
, which is the default.
webpack --config example.config.js
Print result of webpack as a JSON
webpack --json
webpack --json > stats.json
In every other case, webpack prints out a set of stats showing bundle, chunk and timing details. Using this option, the output can be a JSON object. This response is accepted by webpack's analyse tool, or chrisbateman's webpack-visualizer, or th0r's webpack-bundle-analyzer. The analyse tool will take in the JSON and provide all the details of the build in graphical form.
When the webpack configuration exports a function, an "environment" may be passed to it.
webpack --env.production # sets env.production == true
webpack --env.platform=web # sets env.platform == "web"
The --env
argument accepts various syntaxes:
Invocation | Resulting environment |
---|---|
Invocation Resulting environment
|
"prod" |
Invocation Resulting environment
|
{ prod: true } |
Invocation Resulting environment
|
{ prod: 1 } |
Invocation Resulting environment
|
{ prod: "foo" } |
Invocation Resulting environment
|
{ prod: true, min: true } |
Invocation Resulting environment
|
[{ prod: true }, "min"] |
Invocation Resulting environment
|
{prod: [ "foo", "bar" ]} |
See the environment variables guide for more information on its usage.
Parameter | Explanation | Input type | Default |
---|---|---|---|
Parameter Explanation Input type Default
Path to the config file |
Path to the config file | string | webpack.config.js or webpackfile.js |
Parameter Explanation Input type Default
Preload one or more modules before loading the webpack configuration |
Preload one or more modules before loading the webpack configuration | array | |
Parameter Explanation Input type Default
Name of the config to use |
Name of the config to use | string | |
Parameter Explanation Input type Default
Environment passed to the config, when it is a function |
Environment passed to the config, when it is a function | ||
Parameter Explanation Input type Default
Mode to use, either "development" or "production" |
Mode to use, either "development" or "production" | string |
This set of options allows you to manipulate certain output parameters of your build.
Parameter | Explanation | Input type | Default |
---|---|---|---|
Parameter Explanation Input type Default
The output filename for additional chunks |
The output filename for additional chunks | string | filename with [ id ] instead of [ name ] or [ id ] prefixed |
Parameter Explanation Input type Default
The output filename of the bundle |
The output filename of the bundle | string | [ name ] .js |
Parameter Explanation Input type Default
The name of the JSONP function used for chunk loading |
The name of the JSONP function used for chunk loading | string | webpackJsonp |
Parameter Explanation Input type Default
Expose the exports of the entry point as library |
Expose the exports of the entry point as library | string | |
Parameter Explanation Input type Default
The type for exposing the exports of the entry point as library |
The type for exposing the exports of the entry point as library | string | var |
Parameter Explanation Input type Default
The output path for compilation assets |
The output path for compilation assets | string | Current directory |
Parameter Explanation Input type Default
Include a comment with the request for every dependency |
Include a comment with the request for every dependency | boolean | false |
Parameter Explanation Input type Default
The public path for the assets |
The public path for the assets | string | / |
Parameter Explanation Input type Default
The output filename for the SourceMap |
The output filename for the SourceMap | string | [ name ] .map or [ outputFilename ] .map |
Parameter Explanation Input type Default
Display custom text after build output |
Display custom text after build output | string | Default string is null. You could provide a string such as
=== Build done === |
webpack index=./src/index.js index2=./src/index2.js --output-path='./dist' --output-filename='[name][hash].bundle.js'
| Asset | Size | Chunks | Chunk Names |
|--------------------------------------|---------|-------------|---------------|
| index2740fdca26e9348bedbec.bundle.js | 2.6 kB | 0 [emitted] | index2 |
| index740fdca26e9348bedbec.bundle.js | 2.59 kB | 1 [emitted] | index |
[0] ./src/others.js 29 bytes {0} {1} [built]
[1] ./src/index.js 51 bytes {1} [built]
[2] ./src/index2.js 54 bytes {0} [built]
webpack.js index=./src/index.js index2=./src/index2.js --output-path='./dist' --output-filename='[name][hash].bundle.js' --devtool source-map --output-source-map-filename='[name]123.map'
| Asset | Size | Chunks | Chunk Names |
|--------------------------------------|---------|-------------|---------------|
| index2740fdca26e9348bedbec.bundle.js | 2.76 kB | 0 [emitted] | index2 |
| index740fdca26e9348bedbec.bundle.js | 2.74 kB | 1 [emitted] | index |
| index2123.map | 2.95 kB | 0 [emitted] | index2 |
| index123.map | 2.95 kB | 1 [emitted] | index |
[0] ./src/others.js 29 bytes {0} {1} [built]
[1] ./src/index.js 51 bytes {1} [built]
[2] ./src/index2.js 54 bytes {0} [built]
This set of options allows you to better debug the application containing assets compiled with webpack
Parameter | Explanation | Input type | Default value |
---|---|---|---|
Parameter Explanation Input type Default value
Switch loaders to debug mode |
Switch loaders to debug mode | boolean | false |
Parameter Explanation Input type Default value
Define source map type for the bundled resources |
Define source map type for the bundled resources | string | - |
Parameter Explanation Input type Default value
Print compilation progress in percentage |
Print compilation progress in percentage | boolean | false |
Parameter Explanation Input type Default value
Display details about errors |
Display details about errors | boolean | false |
These options allow you to bind modules as allowed by webpack
Parameter | Explanation | Usage |
---|---|---|
Parameter Explanation Usage
Bind a file extension to a loader |
Bind a file extension to a loader | --module-bind js=babel-loader |
Parameter Explanation Usage
Bind a file extension to a post loader |
Bind a file extension to a post loader | |
Parameter Explanation Usage
Bind a file extension to a pre loader |
Bind a file extension to a pre loader |
These options make the build watch for changes in files of the dependency graph and perform the build again.
Parameter | Explanation |
---|---|
Parameter Explanation
Watch the filesystem for changes |
Watch the filesystem for changes |
Parameter Explanation
Timeout for gathering changes while watching |
Timeout for gathering changes while watching |
Parameter Explanation
The polling interval for watching (also enable polling) |
The polling interval for watching (also enable polling) |
Parameter Explanation
Exit the process when stdin is closed |
Exit the process when stdin is closed |
These options allow you to manipulate optimizations for a production build using webpack
Parameter | Explanation | Plugin Used |
---|---|---|
Parameter Explanation Plugin Used
Try to keep the chunk count below a limit |
Try to keep the chunk count below a limit | LimitChunkCountPlugin |
Parameter Explanation Plugin Used
Try to keep the chunk size above a limit |
Try to keep the chunk size above a limit | MinChunkSizePlugin |
Parameter Explanation Plugin Used
Minimize javascript and switches loaders to minimizing |
Minimize javascript and switches loaders to minimizing | TerserPlugin & LoaderOptionsPlugin |
These allow you to configure the webpack resolver with aliases and extensions.
Parameter | Explanation | Example |
---|---|---|
Parameter Explanation Example
Setup a module alias for resolving |
Setup a module alias for resolving | --resolve-alias jquery-plugin=jquery.plugin |
Parameter Explanation Example
Setup extensions that should be used to resolve modules |
Setup extensions that should be used to resolve modules | --resolve-extensions .es6 .js .ts |
Parameter Explanation Example
Minimize javascript and switches loaders to minimizing |
Minimize javascript and switches loaders to minimizing |
These options allow webpack to display various stats and style them differently in the console output.
Parameter | Explanation | Type |
---|---|---|
Parameter Explanation Type
Force colors on the console [default: enabled for TTY output only] |
Force colors on the console [ default: enabled for TTY output only ] | boolean |
Parameter Explanation Type
Force no colors on the console |
Force no colors on the console | boolean |
Parameter Explanation Type
Select display preset (verbose, detailed, normal, minimal, errors-only, none; since webpack 3.0.0) |
Select display preset (verbose, detailed, normal, minimal, errors-only, none; since webpack 3.0.0) | string |
Parameter Explanation Type
Display also cached modules in the output |
Display also cached modules in the output | boolean |
Parameter Explanation Type
Display also cached assets in the output |
Display also cached assets in the output | boolean |
Parameter Explanation Type
Display chunks in the output |
Display chunks in the output | boolean |
Parameter Explanation Type
Display distance from entry point for each module |
Display distance from entry point for each module | boolean |
Parameter Explanation Type
Display entry points in the output |
Display entry points in the output | boolean |
Parameter Explanation Type
Display details about errors |
Display details about errors | boolean |
Parameter Explanation Type
Exclude modules in the output |
Exclude modules in the output | boolean |
Parameter Explanation Type
Set the maximum number of visible modules in output |
Set the maximum number of visible modules in output | number |
Parameter Explanation Type
Display even excluded modules in the output |
Display even excluded modules in the output | boolean |
Parameter Explanation Type
Scope hoisting fallback trigger (since webpack 3.0.0) |
Scope hoisting fallback trigger (since webpack 3.0.0) | boolean |
Parameter Explanation Type
Display origins of chunks in the output |
Display origins of chunks in the output | boolean |
Parameter Explanation Type
Display information about exports provided from modules |
Display information about exports provided from modules | boolean |
Parameter Explanation Type
Display reasons about module inclusion in the output |
Display reasons about module inclusion in the output | boolean |
Parameter Explanation Type
Display information about used exports in modules (Tree Shaking) |
Display information about used exports in modules (Tree Shaking) | boolean |
Parameter Explanation Type
Hide info about modules |
Hide info about modules | boolean |
Parameter Explanation Type
Sort the assets list by property in asset |
Sort the assets list by property in asset | string |
Parameter Explanation Type
Sort the chunks list by property in chunk |
Sort the chunks list by property in chunk | string |
Parameter Explanation Type
Sort the modules list by property in module |
Sort the modules list by property in module | string |
Parameter Explanation Type
Show more details |
Show more details | boolean |
Parameter | Explanation | Usage |
---|---|---|
Parameter Explanation Usage
Abort the compilation on first error |
Abort the compilation on first error | |
Parameter Explanation Usage
Enable in memory caching [Enabled by default for watch] |
Enable in memory caching [ Enabled by default for watch ] | --cache=false |
Parameter Explanation Usage
Define any free variable, see shimming |
Define any free variable, see shimming | --define process.env.NODE_ENV="'development'" |
Parameter Explanation Usage
Enables Hot Module Replacement |
Enables Hot Module Replacement | --hot=true |
Parameter Explanation Usage
Enables labeled modules [Uses LabeledModulesPlugin] |
Enables labeled modules [ Uses LabeledModulesPlugin ] | |
Parameter Explanation Usage
Enables live reloading |
Enables live reloading | --live-reload=true |
Parameter Explanation Usage
Load this plugin |
Load this plugin | |
Parameter Explanation Usage
Prefetch the particular file |
Prefetch the particular file | --prefetch=./files.js |
Parameter Explanation Usage
Provide these modules as globals, see shimming |
Provide these modules as globals, see shimming | --provide jQuery=jquery |
Parameter Explanation Usage
Path to the records file (reading) |
Path to the records file (reading) | |
Parameter Explanation Usage
Path to the records file (writing) |
Path to the records file (writing) | |
Parameter Explanation Usage
Path to the records file |
Path to the records file | |
Parameter Explanation Usage
The targeted execution environment |
The targeted execution environment | --target='node' |
Shortcut | Replaces |
---|---|
Shortcut Replaces -d
|
--debug --devtool cheap-module-eval-source-map --output-pathinfo |
Shortcut Replaces -p
|
--optimize-minimize --define process.env.NODE_ENV="production"
, see
building for production |
The --profile
option captures timing information for each step of the compilation and includes this in the output.
webpack --profile
⋮
[0] ./src/index.js 90 bytes {0} [built]
factory:22ms building:16ms = 38ms
For each module, the following details are included in the output as applicable:
factory
: time to collect module metadata (e.g. resolving the filename)building
: time to build the module (e.g. loaders and parsing)dependencies
: time to identify and connect the module’s dependenciesPaired with --progress
, --profile
gives you an in-depth idea of which step in the compilation is taking how long. This can help you optimize your build in a more informed manner.
webpack --progress --profile
30ms building modules
1ms sealing
1ms optimizing
0ms basic module optimization
1ms module optimization
1ms advanced module optimization
0ms basic chunk optimization
0ms chunk optimization
1ms advanced chunk optimization
0ms module and chunk tree optimization
1ms module reviving
0ms module order optimization
1ms module id optimization
1ms chunk reviving
0ms chunk order optimization
1ms chunk id optimization
10ms hashing
0ms module assets processing
13ms chunk assets processing
1ms additional chunk assets processing
0ms recording
0ms additional asset processing
26ms chunk asset optimization
1ms asset optimization
6ms emitting
⋮