api-javascript.md

JavaScript API

Vite's JavaScript APIs are fully typed, and it's recommended to use TypeScript or enable JS type checking in VS Code to leverage the intellisense and validation.

createServer

Type Signature:

async function createServer(inlineConfig?: InlineConfig): Promise<ViteDevServer>

Example Usage:

import { fileURLToPath } from 'url'
import { createServer } from 'vite'

const __dirname = fileURLToPath(new URL('.', import.meta.url))

;(async () => {
  const server = await createServer({
    // any valid user config options, plus `mode` and `configFile`
    configFile: false,
    root: __dirname,
    server: {
      port: 1337
    }
  })
  await server.listen()

  server.printUrls()
})()

::: tip NOTE When using createServer and build in the same Node.js process, both functions rely on process.env.NODE_ENV to work properly, which also depends on the mode config option. To prevent conflicting behavior, set process.env.NODE_ENV or the mode of the two APIs to development. Otherwise, you can spawn a child process to run the APIs separately. :::

InlineConfig

The InlineConfig interface extends UserConfig with additional properties:

• configFile: specify config file to use. If not set, Vite will try to automatically resolve one from project root. Set to false to disable auto resolving.
• envFile: Set to false to disable .env files.

ViteDevServer

interface ViteDevServer {
  /**
   * The resolved Vite config object.
   */
  config: ResolvedConfig
  /**
   * A connect app instance
   * - Can be used to attach custom middlewares to the dev server.
   * - Can also be used as the handler function of a custom http server
   *   or as a middleware in any connect-style Node.js frameworks.
   *
   * https://github.com/senchalabs/connect#use-middleware
   */
  middlewares: Connect.Server
  /**
   * Native Node http server instance.
   * Will be null in middleware mode.
   */
  httpServer: http.Server | null
  /**
   * Chokidar watcher instance.
   * https://github.com/paulmillr/chokidar#api
   */
  watcher: FSWatcher
  /**
   * Web socket server with `send(payload)` method.
   */
  ws: WebSocketServer
  /**
   * Rollup plugin container that can run plugin hooks on a given file.
   */
  pluginContainer: PluginContainer
  /**
   * Module graph that tracks the import relationships, url to file mapping
   * and hmr state.
   */
  moduleGraph: ModuleGraph
  /**
   * Programmatically resolve, load and transform a URL and get the result
   * without going through the http request pipeline.
   */
  transformRequest(
    url: string,
    options?: TransformOptions
  ): Promise<TransformResult | null>
  /**
   * Apply Vite built-in HTML transforms and any plugin HTML transforms.
   */
  transformIndexHtml(url: string, html: string): Promise<string>
  /**
   * Load a given URL as an instantiated module for SSR.
   */
  ssrLoadModule(
    url: string,
    options?: { fixStacktrace?: boolean }
  ): Promise<Record<string, any>>
  /**
   * Fix ssr error stacktrace.
   */
  ssrFixStacktrace(e: Error): void
  /**
   * Start the server.
   */
  listen(port?: number, isRestart?: boolean): Promise<ViteDevServer>
  /**
   * Restart the server.
   *
   * @param forceOptimize - force the optimizer to re-bundle, same as --force cli flag
   */
  restart(forceOptimize?: boolean): Promise<void>
  /**
   * Stop the server.
   */
  close(): Promise<void>
}

build

Type Signature:

async function build(
  inlineConfig?: InlineConfig
): Promise<RollupOutput | RollupOutput[]>

Example Usage:

import path from 'path'
import { fileURLToPath } from 'url'
import { build } from 'vite'

const __dirname = fileURLToPath(new URL('.', import.meta.url))

;(async () => {
  await build({
    root: path.resolve(__dirname, './project'),
    base: '/foo/',
    build: {
      rollupOptions: {
        // ...
      }
    }
  })
})()

preview

Type Signature:

async function preview(inlineConfig?: InlineConfig): Promise<PreviewServer>

Example Usage:

import { preview } from 'vite'
;(async () => {
  const previewServer = await preview({
    // any valid user config options, plus `mode` and `configFile`
    preview: {
      port: 8080,
      open: true
    }
  })

  previewServer.printUrls()
})()

resolveConfig

Type Signature:

async function resolveConfig(
  inlineConfig: InlineConfig,
  command: 'build' | 'serve',
  defaultMode?: string
): Promise<ResolvedConfig>

The command value is serve in dev (in the cli vite, vite dev, and vite serve are aliases).

transformWithEsbuild

Type Signature:

async function transformWithEsbuild(
  code: string,
  filename: string,
  options?: EsbuildTransformOptions,
  inMap?: object
): Promise<ESBuildTransformResult>