1. serve-static
Serve static files
serve-static
Package: serve-static
Created by: expressjs
Last modified: Wed, 27 Mar 2024 17:00:24 GMT
Version: 1.15.0
License: MIT
Downloads: 126,674,958
Repository: https://github.com/expressjs/serve-static

Install

npm install serve-static
yarn add serve-static

serve-static

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Install

This is a Node.js module available through the
npm registry. Installation is done using the
npm install command:

 $ npm install serve-static

API

 var serveStatic = require('serve-static')

serveStatic(root, options)

Create a new middleware function to serve files from within a given root
directory. The file to serve will be determined by combining req.url
with the provided root directory. When a file is not found, instead of
sending a 404 response, this module will instead call next() to move on
to the next middleware, allowing for stacking and fall-backs.

Options

acceptRanges

Enable or disable accepting ranged requests, defaults to true.
Disabling this will not send Accept-Ranges and ignore the contents
of the Range request header.

cacheControl

Enable or disable setting Cache-Control response header, defaults to
true. Disabling this will ignore the immutable and maxAge options.

dotfiles

Set how "dotfiles" are treated when encountered. A dotfile is a file
or directory that begins with a dot ("."). Note this check is done on
the path itself without checking if the path actually exists on the
disk. If root is specified, only the dotfiles above the root are
checked (i.e. the root itself can be within a dotfile when set
to "deny").

  • 'allow' No special treatment for dotfiles.
  • 'deny' Deny a request for a dotfile and 403/next().
  • 'ignore' Pretend like the dotfile does not exist and 404/next().

The default value is 'ignore'.

etag

Enable or disable etag generation, defaults to true.

extensions

Set file extension fallbacks. When set, if a file is not found, the given
extensions will be added to the file name and search for. The first that
exists will be served. Example: ['html', 'htm'].

The default value is false.

fallthrough

Set the middleware to have client errors fall-through as just unhandled
requests, otherwise forward a client error. The difference is that client
errors like a bad request or a request to a non-existent file will cause
this middleware to simply next() to your next middleware when this value
is true. When this value is false, these errors (even 404s), will invoke
next(err).

Typically true is desired such that multiple physical directories can be
mapped to the same web address or for routes to fill in non-existent files.

The value false can be used if this middleware is mounted at a path that
is designed to be strictly a single file system directory, which allows for
short-circuiting 404s for less overhead. This middleware will also reply to
all methods.

The default value is true.

immutable

Enable or disable the immutable directive in the Cache-Control response
header, defaults to false. If set to true, the maxAge option should
also be specified to enable caching. The immutable directive will prevent
supported clients from making conditional requests during the life of the
maxAge option to check if the file has changed.

index

By default this module will send "index.html" files in response to a request
on a directory. To disable this set false or to supply a new index pass a
string or an array in preferred order.

lastModified

Enable or disable Last-Modified header, defaults to true. Uses the file
system's last modified value.

maxAge

Provide a max-age in milliseconds for http caching, defaults to 0. This
can also be a string accepted by the ms
module.

redirect

Redirect to trailing "/" when the pathname is a dir. Defaults to true.

setHeaders

Function to set custom headers on response. Alterations to the headers need to
occur synchronously. The function is called as fn(res, path, stat), where
the arguments are:

  • res the response object
  • path the file path that is being sent
  • stat the stat object of the file that is being sent

Examples

Serve files with vanilla node.js http server

 var finalhandler = require('finalhandler')
var http = require('http')
var serveStatic = require('serve-static')

// Serve up public/ftp folder
var serve = serveStatic('public/ftp', { index: ['index.html', 'index.htm'] })

// Create server
var server = http.createServer(function onRequest (req, res) {
  serve(req, res, finalhandler(req, res))
})

// Listen
server.listen(3000)

Serve all files as downloads

 var contentDisposition = require('content-disposition')
var finalhandler = require('finalhandler')
var http = require('http')
var serveStatic = require('serve-static')

// Serve up public/ftp folder
var serve = serveStatic('public/ftp', {
  index: false,
  setHeaders: setHeaders
})

// Set header to force download
function setHeaders (res, path) {
  res.setHeader('Content-Disposition', contentDisposition(path))
}

// Create server
var server = http.createServer(function onRequest (req, res) {
  serve(req, res, finalhandler(req, res))
})

// Listen
server.listen(3000)

Serving using express

Simple

This is a simple example of using Express.

 var express = require('express')
var serveStatic = require('serve-static')

var app = express()

app.use(serveStatic('public/ftp', { index: ['default.html', 'default.htm'] }))
app.listen(3000)

Multiple roots

This example shows a simple way to search through multiple directories.
Files are searched for in public-optimized/ first, then public/ second
as a fallback.

 var express = require('express')
var path = require('path')
var serveStatic = require('serve-static')

var app = express()

app.use(serveStatic(path.join(__dirname, 'public-optimized')))
app.use(serveStatic(path.join(__dirname, 'public')))
app.listen(3000)

Different settings for paths

This example shows how to set a different max age depending on the served
file. In this example, HTML files are not cached, while everything else
is for 1 day.

 var express = require('express')
var path = require('path')
var serveStatic = require('serve-static')

var app = express()

app.use(serveStatic(path.join(__dirname, 'public'), {
  maxAge: '1d',
  setHeaders: setCustomCacheControl
}))

app.listen(3000)

function setCustomCacheControl (res, file) {
  if (path.extname(file) === '.html') {
    // Custom Cache-Control for HTML files
    res.setHeader('Cache-Control', 'public, max-age=0')
  }
}

License

MIT

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