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title: Less layout: default stylesheet: docs

Less rules for Bazel

WARNING: this is beta-quality software. Breaking changes are likely. Not recommended for production use without expert support.

The Less rules run the Less CSS preprocessor with Bazel.

Installation

Add the @bazel/less npm package to your devDependencies in package.json.

Your WORKSPACE should declare a yarn_install or npm_install rule named npm. It should then install the rules found in the npm packages using the install_bazel_dependencies function. See https://github.com/bazelbuild/rules_nodejs/#quickstart

This causes the @bazel/less package to be installed as a Bazel workspace named npm_bazel_less.

Installing with self-managed dependencies

If you didn‘t use the yarn_install or npm_install rule to create an npm workspace, you’ll have to declare a rule in your root BUILD.bazel file to execute less:

# Create a less rule to use in less_binary#compiler
# attribute when using self-managed dependencies
nodejs_binary(
    name = "less_bin",
    entry_point = "//:node_modules/less/bin/lessc",
    # Point bazel to your node_modules to find the entry point
    node_modules = ["//:node_modules"],
)

less_binary

Usage

less_binary(name, compiler, deps, sourcemap, src)

name

(name, mandatory): A unique name for this target.

compiler

(label): Label that points to the lessc binary to run. If you install your npm packages to a workspace named something other than “npm”, you may need to set this to @my_npm_name//@bazel/less/bin:less

deps

(labels)

sourcemap

(Boolean): Generates a sourcemap

src

(label, mandatory)