feat: support importing json

package.json

@@ -52,6 +52,7 @@
   "dependencies": {
     "@babel/parser": "^7.9.4",
     "@rollup/plugin-alias": "^3.1.0",
+    "@rollup/plugin-json": "^4.0.3",
     "@rollup/plugin-node-resolve": "^7.1.3",
     "@rollup/plugin-replace": "^2.3.2",
     "@types/koa": "^2.11.3",

src/node/build.ts

@@ -97,6 +97,7 @@ export async function build(options: BuildOptions = {}): Promise<BuildResult> {
         // TODO proxy cssModules config
         ...rollupPluginVueOptions
       }),
+      require('@rollup/plugin-json')(),
       require('@rollup/plugin-node-resolve')({
         rootDir: root
       }),

src/node/server.ts

@@ -7,6 +7,7 @@ import { moduleResolvePlugin } from './serverPluginModuleResolve'
 import { vuePlugin } from './serverPluginVue'
 import { hmrPlugin, HMRWatcher } from './serverPluginHmr'
 import { serveStaticPlugin } from './serverPluginServeStatic'
+import { jsonPlugin } from './serverPluginJson'
 
 export { Resolver }
 
@@ -30,6 +31,7 @@ const internalPlugins: Plugin[] = [
   moduleRewritePlugin,
   moduleResolvePlugin,
   vuePlugin,
+  jsonPlugin,
   hmrPlugin,
   serveStaticPlugin
 ]

src/node/serverPluginJson.ts

@@ -0,0 +1,17 @@
+import { Plugin } from './server'
+import { readBody } from './utils'
+
+export const jsonPlugin: Plugin = ({ app }) => {
+  app.use(async (ctx, next) => {
+    await next()
+    // handle .json imports
+    if (ctx.path.endsWith('.json')) {
+      const referer = ctx.get('referer')
+      // only rewrite json if referer is not a page (fetch/ajax requests)
+      if (/\.\w+$/.test(referer) && !referer.endsWith('.html')) {
+        ctx.type = 'js'
+        ctx.body = `export default ${await readBody(ctx.body)}`
+      }
+    }
+  })
+}

src/node/serverPluginModuleRewrite.ts

@@ -3,7 +3,6 @@ import path from 'path'
 import slash from 'slash'
 import LRUCache from 'lru-cache'
 import MagicString from 'magic-string'
-import { Readable } from 'stream'
 import { init as initLexer, parse as parseImports } from 'es-module-lexer'
 import { InternalResolver } from './resolver'
 import {
@@ -14,6 +13,7 @@ import {
   rewriteFileWithHMR,
   hmrClientPublicPath
 } from './serverPluginHmr'
+import { readBody } from './utils'
 
 const debug = require('debug')('vite:rewrite')
 
@@ -105,22 +105,6 @@ export const moduleRewritePlugin: Plugin = ({ app, watcher, resolver }) => {
   })
 }
 
-async function readBody(stream: Readable | string): Promise<string> {
-  if (stream instanceof Readable) {
-    return new Promise((resolve, reject) => {
-      let res = ''
-      stream
-        .on('data', (chunk) => (res += chunk))
-        .on('error', reject)
-        .on('end', () => {
-          resolve(res)
-        })
-    })
-  } else {
-    return stream
-  }
-}
-
 function rewriteImports(
   source: string,
   importer: string,

src/node/utils.ts

@@ -3,6 +3,7 @@ import { promises as fs } from 'fs'
 import LRUCache from 'lru-cache'
 import os from 'os'
 import { Context } from 'koa'
+import { Readable } from 'stream'
 
 const imageRE = /\.(png|jpe?g|gif|svg)(\?.*)?$/
 const mediaRE = /\.(mp4|webm|ogg|mp3|wav|flac|aac)(\?.*)?$/
@@ -62,6 +63,24 @@ export async function cachedRead(
   return content
 }
 
+export async function readBody(
+  stream: Readable | Buffer | string
+): Promise<string> {
+  if (stream instanceof Readable) {
+    return new Promise((resolve, reject) => {
+      let res = ''
+      stream
+        .on('data', (chunk) => (res += chunk))
+        .on('error', reject)
+        .on('end', () => {
+          resolve(res)
+        })
+    })
+  } else {
+    return typeof stream === 'string' ? stream : stream.toString()
+  }
+}
+
 export function getIPv4AddressList(): string[] {
   const networkInterfaces = os.networkInterfaces()
   let result: string[] = []

yarn.lock

@@ -451,6 +451,13 @@
   dependencies:
     slash "^3.0.0"
 
+"@rollup/plugin-json@^4.0.3":
+  version "4.0.3"
+  resolved "https://registry.yarnpkg.com/@rollup/plugin-json/-/plugin-json-4.0.3.tgz#747e2c2884c5a0fa00b66c9c0f3f1012cddca534"
+  integrity sha512-QMUT0HZNf4CX17LMdwaslzlYHUKTYGuuk34yYIgZrNdu+pMEfqMS55gck7HEeHBKXHM4cz5Dg1OVwythDdbbuQ==
+  dependencies:
+    "@rollup/pluginutils" "^3.0.8"
+
 "@rollup/plugin-node-resolve@^7.1.3":
   version "7.1.3"
   resolved "https://registry.yarnpkg.com/@rollup/plugin-node-resolve/-/plugin-node-resolve-7.1.3.tgz#80de384edfbd7bfc9101164910f86078151a3eca"