set-webpack-public-path plugin for webpack
Installation
npm install @rushstack/set-webpack-public-path-plugin --save-dev
Mode 1: Using the document.currentScript
API
Overview
This plugin wraps the entire webpack bundle in an immediately executed function expression (IIFE) that sets a variable
to the value of document.currentScript
and then injects code that extracts the current script's base path from
the src
attribute when setting the __webpack_public_path__
variable.
This is similar to the output.publicPath = 'auto'
option, but differs in two important ways:
- It does not contain any fallback logic to look at
<script />
elements - It stores the
document.currentScript
value immediately when the bundle is executed, not when
the runtime is executed. This is important when the bundle's factory function is called by another script, like
when an AMD output target is produced.
Plugin
To use the plugin, add it to the plugins
array of your Webpack config. For example:
import { SetPublicPathCurrentScriptPlugin } from '@rushstack/set-webpack-public-path-plugin';
{
plugins: [
new SetPublicPathCurrentScriptPlugin()
]
}
Options
This plugin has no options.
Mode 2: Automatic public path detection via regular expression
Overview
This simple plugin uses a specified regular expression or the emitted asset name to set the __webpack_public_path__
variable. This is useful for scenarios where the Webpack automatic public path detection does not work. For example,
when emitting AMD-style assets that are initialized by a callback.
Plugin
To use the plugin, add it to the plugins
array of your Webpack config. For example:
import { SetPublicPathPlugin } from '@rushstack/set-webpack-public-path-plugin';
{
plugins: [
new SetPublicPathPlugin( )
]
}
Options
scriptName = { }
This parameter is an object that takes three properties: a string property name
, a boolean property isTokenized
,
and a boolean property useAssetName
The name
property is a regular expression string that is applied to all script URLs on the page. The last directory
of the URL that matches the regular expression is used as the public path. For example, if the name
property
is set to my\-bundle_?[a-zA-Z0-9-_]*\.js
and a script's URL is https://mycdn.net/files/build_id/assets/my-bundle_10fae182eb.js
,
the public path will be set to https://mycdn.net/files/build_id/assets/
.
If the isTokenized
parameter is set to true
, the regular expression string in name
is treated as a tokenized
string. The supported tokens are [name]
and [hash]
. Instances of the [name]
substring are replaced with the
chunk's name, and instances of the [hash]
substring are replaced with the chunk's rendered hash. The name
is regular expression-escaped. For example, if the name
property is set to [name]_?[a-zA-Z0-9-_]*\.js
,
isTokenized
is set to true
, and the chunk's name is my-bundle
, and a script's URL is
https://mycdn.net/files/build_id/assets/my-bundle_10fae182eb.js
, the public path will be set to
https://mycdn.net/files/build_id/assets/
.
If the useAssetName
property is set, the plugin will use the Webpack-produced asset name as it would the name
property. useAssetName
is exclusive to name
and isTokenized
.
This option is exclusive to other options. If it is set, systemJs
, publicPath
, and urlPrefix
will be ignored.
regexVariable = '...'
Check for a variable with name ...
on the page and use its value as a regular expression against script paths to
the bundle's script. If a value foo
is passed into regexVariable
, the produced bundle will look for a variable
called foo
during initialization, and if a foo
variable is found, use its value as a regular expression to
detect the bundle's script.
For example, if the regexVariable
option is set to scriptRegex
and scriptName
is set to { name: 'myscript' }
,
consider two cases:
Case 1
<html>
<head>
<script>
var scriptRegex = /thescript/i;
</script>
<script src="theScript.js"></script>
</head>
...
</html>
In this case, because there is a scriptRegex
variable defined on the page, the bundle will use its value
(/thescript/i
) to find the script.
Case 2
<html>
<head>
<script src="myScript.js"></script>
</head>
...
</html>
In this case, because there is not a scriptRegex
variable defined on the page, the bundle will use the value
passed into the scriptName
option to find the script.
getPostProcessScript = (variableName) => { ... }
A function that returns a snippet of code that manipulates the variable with the name that's specified in the
parameter. If this parameter isn't provided, no post-processing code is included. The variable must be modified
in-place - the processed value should not be returned. This is useful when non-entry assets are deployed to
a parent directory or subdirectory of the directory to which the entry assets are deployed.
For example, if this parameter is set to this function
getPostProcessScript = (variableName) => {
return `${variableName} = ${variableName} + 'assets/';`;
};
the public path variable will have /assets/
appended to the found path.
Note that the existing value of the variable already ends in a slash (/
).
preferLastFoundScript = false
If true, find the last script matching the regexVariable (if it is set). If false, find the first matching script.
This can be useful if there are multiple scripts loaded in the DOM that match the regexVariable.