source-map-loader
Extracts source maps from existing source files (from their sourceMappingURL
).
Getting Started
To begin, you'll need to install source-map-loader
:
npm i -D source-map-loader
or
yarn add -D source-map-loader
or
pnpm add -D source-map-loader
Then add the plugin to your webpack
config. For example:
file.js
import css from "file.css";
webpack.config.js
module.exports = {
module: {
rules: [
{
test: /\.js$/,
enforce: "pre",
use: ["source-map-loader"],
},
],
},
};
The source-map-loader
extracts existing source maps from all JavaScript entries.
This includes both inline source maps as well as those linked via URL.
All source map data is passed to webpack for processing as per a chosen source map style specified by the devtool
option in webpack.config.js.
This loader is especially useful when using 3rd-party libraries having their own source maps.
If not extracted and processed into the source map of the webpack bundle, browsers may misinterpret source map data. source-map-loader
allows webpack to maintain source map data continuity across libraries so ease of debugging is preserved.
The source-map-loader
will extract from any JavaScript file, including those in the node_modules
directory.
Be mindful in setting include and exclude rule conditions to maximize bundling performance.
And run webpack
via your preferred method.
Options
Name | Type | Default | Description |
---|---|---|---|
filterSourceMappingUrl |
{Function} |
undefined |
Allows to control SourceMappingURL behaviour |
filterSourceMappingUrl
Type: Function
Default: undefined
Allows you to specify the behavior of the loader for SourceMappingURL
comment.
The function must return one of the values:
-
true
or'consume'
- consume the source map and removeSourceMappingURL
comment (default behavior) -
false
or'remove'
- do not consume the source map and removeSourceMappingURL
comment -
skip
- do not consume the source map and do not removeSourceMappingURL
comment
Example configuration:
webpack.config.js
module.exports = {
module: {
rules: [
{
test: /\.js$/,
enforce: "pre",
use: [
{
loader: "source-map-loader",
options: {
filterSourceMappingUrl: (url, resourcePath) => {
if (/broker-source-map-url\.js$/i.test(url)) {
return false;
}
if (/keep-source-mapping-url\.js$/i.test(resourcePath)) {
return "skip";
}
return true;
},
},
},
],
},
],
},
};
Examples
Ignoring Warnings
To ignore warnings, you can use the following configuration:
webpack.config.js
module.exports = {
module: {
rules: [
{
test: /\.js$/,
enforce: "pre",
use: ["source-map-loader"],
},
],
},
ignoreWarnings: [/Failed to parse source map/],
};
More information about the ignoreWarnings
option can be found here
Contributing
Please take a moment to read our contributing guidelines if you haven't yet done so.