CLI#

Rslib comes with a lightweight CLI that includes commands such as build and inspect.

rslib -h#

To view all available CLI commands, run the following command in the project directory:

npx rslib -h

The output is shown below:

Usage: rslib <command> [options]

Options:
  -V, --version       output the version number
  -h, --help          display help for command

Commands:
  build [options]     build the library for production
  inspect [options]   inspect the Rsbuild / Rspack configs of Rslib projects
  mf [options] <dev>  start Rsbuild dev server of Module Federation format
  help [command]      display help for command

rslib build#

The rslib build command will build the outputs for production in the dist/ directory by default.

Usage: rslib build [options]

build the library for production

Options:
  -c --config <config>  specify the configuration file, can be a relative or absolute path
  -r --root <root>      specify the project root directory, can be an absolute path or a path relative to cwd
  --env-mode <mode>     specify the env mode to load the `.env.[mode]` file
  --env-dir <dir>       specify the directory to load `.env` files
  --lib <id>            build the specified library (may be repeated)
  -w --watch            turn on watch mode, watch for changes and rebuild
  -h, --help            display help for command

Environment Variables#

Rslib supports injecting env variables or expressions into the code during build, which is helpful for distinguishing the running environment or replacing constants.

You can see more details in Environment Variables.

Env Mode#

Rslib supports reading .env.[mode] and .env.[mode].local files. You can specify the env mode using the --env-mode <mode> flag.

For example, set the env mode as test:

npx rslib build --env-mode test

Rslib will then read the following files in sequence:

• .env
• .env.local
• .env.test
• .env.test.local

Env Directory#

By default, the .env file is located in the root directory of the project. You can specify the env directory by using the --env-dir <dir> option in the CLI.

For example, to specify the env directory as config:

npx rslib build --env-dir config

In this case, Rslib will read the ./config/.env and other env files.

Example#

For example, create a .env file and add the following contents:

FOO=hello
BAR=1

Then in the rslib.config.ts file, you can access the above env variables using import.meta.env.[name] or process.env.[name]:

console.log(import.meta.env.FOO); // 'hello'
console.log(import.meta.env.BAR); // '1'

console.log(process.env.FOO); // 'hello'
console.log(process.env.BAR); // '1'

Now, create a .env.local file and add the following contents:

BAR=2

The value of BAR is overwritten to '2':

console.log(import.meta.env.BAR); // '2'
console.log(process.env.BAR); // '2'

Watch Mode#

You can use rslib build --watch to turn on watch mode for watching for changes and rebuild.

Filter Libraries#

You can use the --lib option to build specific libraries. The --lib option can be repeated to build multiple libraries. Check out the lib.id to learn how to get or set the library ID.

rslib inspect#

The rslib inspect command is used to view the Rsbuild config and Rspack config of the Rslib project.

Usage: rslib inspect [options]

inspect the Rsbuild / Rspack configs of Rslib projects

Options:
  -c --config <config>  specify the configuration file, can be a relative or absolute path
  -r --root <root>      specify the project root directory, can be an absolute path or a path relative to cwd
  --env-mode <mode>     specify the env mode to load the `.env.[mode]` file
  --env-dir <dir>       specify the directory to load `.env` files
  --lib <id>            inspect the specified library (may be repeated)
  --output <output>     specify inspect content output path (default: ".rsbuild")
  --verbose             show full function definitions in output
  -h, --help            display help for command

When you run the command npx rslib inspect in the project root directory, the following files will be generated in the dist/.rsbuild directory of the project:

• rsbuild.config.mjs: Represents the Rsbuild configuration used during the build.
• rspack.config.web.mjs: Represents the Rspack configuration used during the build.

➜ npx rslib inspect

Inspect config succeed, open following files to view the content:

  - Rsbuild Config: /project/dist/.rsbuild/rsbuild.config.mjs
  - Rspack Config (esm): /project/dist/.rsbuild/rspack.config.esm.mjs

Verbose Content#

By default, the inspect command omits the content of functions in the configuration object. You can add the --verbose option to output the complete content of functions:

rslib inspect --verbose

Multiple Output Formats#

If the current project has multiple output formats, such as ESM artifact and CJS artifact simultaneously, multiple Rspack configuration files will be generated in the dist/.rsbuild directory.

➜ npx rslib inspect

Inspect config succeed, open following files to view the content:

  - Rsbuild Config (esm): /project/dist/.rsbuild/rsbuild.config.esm.mjs
  - Rsbuild Config (cjs): /project/dist/.rsbuild/rsbuild.config.cjs.mjs
  - Rspack Config (esm): /project/dist/.rsbuild/rspack.config.esm.mjs
  - Rspack Config (cjs): /project/dist/.rsbuild/rspack.config.cjs.mjs

Filter Libraries#

You can use the --lib option to inspect specific libraries. The --lib option can be repeated to inspect multiple libraries. Check out the lib.id to learn how to get or set the library ID.

rslib mf dev#

The rslib mf dev command is utilized to start Rsbuild dev server of Module Federation format.

This enables you to develop your mf format module within the host app more rapidly.

Usage: rslib mf [options] <dev>

start Rsbuild dev server of Module Federation format

Options:
  -c --config <config>  specify the configuration file, can be a relative or absolute path
  -r --root <root>      specify the project root directory, can be an absolute path or a path relative to cwd
  --env-mode <mode>     specify the env mode to load the `.env.[mode]` file
  --env-dir <dir>       specify the directory to load `.env` files
  -h, --help            display help for command