@astrojs/compiler

What is @astrojs/compiler?

@astrojs/compiler is a package designed to compile Astro components into static HTML and JavaScript. It is part of the Astro framework, which is focused on building fast, content-focused websites. The compiler transforms Astro component files (.astro) into optimized static assets.

What are @astrojs/compiler's main functionalities?

Compile Astro Components

This feature allows you to compile Astro component code into static HTML and JavaScript. The `compile` function takes Astro code as input and returns a promise that resolves to the compiled result.

const { compile } = require('@astrojs/compiler');
const astroCode = `<div>Hello, World!</div>`;
compile(astroCode).then(result => {
  console.log(result);
});

Transform Astro Files

The `transform` function is used to transform Astro files into a format that can be further processed or optimized. It takes the content of an Astro file and returns a promise that resolves to the transformed result.

const { transform } = require('@astrojs/compiler');
const astroFileContent = `<div>Hello, World!</div>`;
transform(astroFileContent).then(result => {
  console.log(result);
});

Optimize Output

This feature allows you to optimize the output of the compiled Astro components. By passing an options object with `optimize: true`, the compiler will produce optimized static assets.

const { compile } = require('@astrojs/compiler');
const astroCode = `<div>Hello, World!</div>`;
compile(astroCode, { optimize: true }).then(result => {
  console.log(result);
});

Other packages similar to @astrojs/compiler

svelte

Svelte is a compiler that converts Svelte components into highly optimized JavaScript at build time. Unlike Astro, which focuses on static site generation, Svelte is more geared towards building reactive user interfaces.

vue-template-compiler

Vue Template Compiler is used to compile Vue.js templates into render functions. It is similar to @astrojs/compiler in that it transforms component code into optimized output, but it is specific to the Vue.js framework.

babel

Babel is a JavaScript compiler that transforms modern JavaScript code into a backward-compatible version. While it is not specific to any framework, it provides similar functionality in terms of code transformation and optimization.

README

Astro Compiler

Astro’s Go + WASM compiler.

Install

npm install @astrojs/compiler

Usage

Transform .astro to valid TypeScript

The Astro compiler can convert .astro syntax to a TypeScript Module whose default export generates HTML.

Some notes...

• TypeScript is valid .astro syntax! The output code may need an additional post-processing step to generate valid JavaScript.
• .astro files rely on a server implementation exposed as astro/runtime/server/index.js in the Node ecosystem. Other runtimes currently need to bring their own rendering implementation and reference it via internalURL. This is a pain point we're looking into fixing.

import { transform, type TransformResult } from "@astrojs/compiler";

const result = await transform(source, {
  filename: "/Users/astro/Code/project/src/pages/index.astro",
  sourcemap: "both",
  internalURL: "astro/runtime/server/index.js",
});

Parse .astro and return an AST

The Astro compiler can emit an AST using the parse method.

Some notes...

• Position data is currently incomplete and in some cases incorrect. We're working on it!
• A TextNode can represent both HTML text and JavaScript/TypeScript source code.
• The @astrojs/compiler/utils entrypoint exposes walk and walkAsync functions that can be used to traverse the AST. It also exposes the is helper which can be used as guards to derive the proper types for each node.

import { parse } from "@astrojs/compiler";
import { walk, walkAsync, is } from "@astrojs/compiler/utils";

const result = await parse(source, {
  position: false, // defaults to `true`
});

walk(result.ast, (node) => {
  // `tag` nodes are `element` | `custom-element` | `component`
  if (is.tag(node)) {
    console.log(node.name);
  }
});

await walkAsync(result.ast, async (node) => {
  if (is.tag(node)) {
    node.value = await expensiveCalculation(node)
  }
});

Develop

VSCode / CodeSpaces

A devcontainer configuration is available for use with VSCode's Remote Development extension pack and GitHub CodeSpaces.

Contributing

CONTRIBUTING.md