feat: add http import (#34)

Co-authored-by: loynoir <[email protected]>

Author: loynoir

loader.mjs

@@ -2,9 +2,11 @@ import { URL, pathToFileURL, fileURLToPath } from 'url'
 import fs from 'fs'
 import { dirname } from 'path'
 import { transformSync, build } from 'esbuild'
+import fetch from 'node-fetch'
 
 const isWindows = process.platform === 'win32'
 
+const httpRegex = /^https?:\/\//
 const extensionsRegex = /\.m?(tsx?|json)$/
 
 async function esbuildResolve(id, dir) {
@@ -95,6 +97,13 @@ export async function resolve(specifier, context, defaultResolve) {
     parentURL,
   } = context
 
+  if (httpRegex.test(specifier) || httpRegex.test(parentURL)) {
+    return {
+      url: new URL(specifier, parentURL).href,
+      format: 'module',
+    }
+  }
+
   let url
 
   // According to Node's algorithm, we first check if it is a valid URL.
@@ -131,7 +140,14 @@ export async function resolve(specifier, context, defaultResolve) {
 
 // New hook starting from Node v16.12.0
 // See: https://github.com/nodejs/node/pull/37468
-export function load(url, context, defaultLoad) {
+export async function load(url, context, defaultLoad) {
+  if (httpRegex.test(url)) {
+    return {
+      format: 'module',
+      source: await (await fetch(url)).text(),
+    }
+  }
+
   if (extensionsRegex.test(new URL(url).pathname)) {
     const { format } = context
 
@@ -152,6 +168,12 @@ export function load(url, context, defaultLoad) {
 }
 
 export function getFormat(url, context, defaultGetFormat) {
+  if (httpRegex.test(url)) {
+    return {
+      format: 'module',
+    }
+  }
+
   if (extensionsRegex.test(new URL(url).pathname)) {
     return {
       format: 'module',
@@ -162,9 +184,16 @@ export function getFormat(url, context, defaultGetFormat) {
   return defaultGetFormat(url, context, defaultGetFormat)
 }
 
-export function transformSource(source, context, defaultTransformSource) {
+export async function transformSource(source, context, defaultTransformSource) {
   const { url, format } = context
 
+  if (httpRegex.test(url)) {
+    return {
+      format: 'module',
+      source: await (await fetch(url)).text(),
+    }
+  }
+
   if (extensionsRegex.test(new URL(url).pathname)) {
     let filename = url
     if (!isWindows) filename = fileURLToPath(url)
@@ -179,3 +208,13 @@ export function transformSource(source, context, defaultTransformSource) {
   // Let Node.js handle all other sources.
   return defaultTransformSource(source, context, defaultTransformSource)
 }
+
+export async function getSource(url, context, defaultGetSource) {
+  if (httpRegex.test(url)) {
+    return {
+      source: await (await fetch(url)).text(),
+    }
+  }
+
+  return defaultGetSource(url, context, defaultGetSource)
+}

package.json

@@ -33,7 +33,8 @@
     "test": "node --experimental-loader ./loader.mjs test/entry.ts"
   },
   "dependencies": {
-    "esbuild": ">=0.13.12"
+    "esbuild": ">=0.13.12",
+    "node-fetch": "^3.2.1"
   },
   "devDependencies": {
     "@antfu/eslint-config": "^0.16.1",

pnpm-lock.yaml

@@ -116,6 +116,15 @@ test('import json', async() => {
   assert(stdout === 'esbuild-node-loader')
 })
 
+test('http import', async() => {
+  const { stdout } = await execa('node', [
+    '--experimental-loader',
+    relativize(`${cwd}/loader.mjs`),
+    relativize(`${cwd}/test/fixture.http.ts`),
+  ])
+  assert(stdout === 'fooBar')
+})
+
 test('tsconfig-paths', async() => {
   const cwd2 = `${cwd}/test/tsconfig-paths`
   const { stdout } = await execa('node', [

test/entry.ts

@@ -0,0 +1,3 @@
+import camelCase from 'https://jspm.dev/[email protected]'
+
+console.log(camelCase('foo-bar'))