@rollup/plugin-replace
🍣 A Rollup plugin which replaces strings in files while bundling.
Requirements
This plugin requires an LTS Node version (v8.0.0+) and Rollup v1.20.0+.
Install
Using npm:
npm install @rollup/plugin-replace --save-dev
Usage
Create a rollup.config.js configuration file and import the plugin:
import replace from '@rollup/plugin-replace';
export default {
input: 'src/index.js',
output: {
dir: 'output',
format: 'cjs'
},
plugins: [
replace({
__buildEnv__: 'production',
__buildDate__: () => new Date(),
__buildVersion: 15
})
]
};
Then call rollup either via the CLI or the API.
The configuration above will replace every instance of __buildEnv__ with 'production' and __buildDate__ with the result of the given function in any file included in the build. Note: Values have to be either primitives or functions that return a string. For complex values, use JSON.stringify.
Typically, @rollup/plugin-replace should be placed in plugins before other plugins so that they may apply optimizations, such as dead code removal.
The most popular case is replacing process.env.NODE_ENV with development or production environment.
import replace from '@rollup/plugin-replace';
export default {
input: 'src/index.js',
output: {
dir: 'output',
format: 'cjs'
},
plugins: [
replace({
// alternatively, one could pass process.env.NODE_ENV or 'development` to stringify
'process.env.NODE_ENV': JSON.stringify('production')
})
]
};
Options
In addition to the properties and values specified for replacement, users may also specify the options below.
delimiters
Type: Array[...String, String]
Default: ['\b', '\b']
Specifies the boundaries around which strings will be replaced. By default, delimiters are word boundaries. See Word Boundaries below for more information.
exclude
Type: String | Array[...String]
Default: null
A minimatch pattern, or array of patterns, which specifies the files in the build the plugin should ignore. By default no files are ignored.
include
Type: String | Array[...String]
Default: null
A minimatch pattern, or array of patterns, which specifies the files in the build the plugin should operate on. By default all files are targeted.
Word Boundaries
By default, values will only match if they are surrounded by word boundaries.
Consider the following options and build file:
module.exports = {
...
plugins: [replace({ changed: 'replaced' })]
};
// file.js
console.log('changed');
console.log('unchanged');
The result would be:
// file.js
console.log('replaced');
console.log('unchanged');
To ignore word boundaries and replace every instance of the string, wherever it may be, specify empty strings as delimiters:
export default {
...
plugins: [
replace({
changed: 'replaced',
delimiters: ['', '']
})
]
};