You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

239 lines
8.8 KiB

This file contains ambiguous Unicode characters!

This file contains ambiguous Unicode characters that may be confused with others in your current locale. If your use case is intentional and legitimate, you can safely ignore this warning. Use the Escape button to highlight these characters.

# sirv ![CI](https://github.com/lukeed/sirv/workflows/CI/badge.svg)
> The optimized and lightweight middleware for serving requests to static assets
You may use `sirv` as a *very* fast and lightweight alternative to [`serve-static`](https://www.npmjs.com/package/serve-static).
The massive performance advantage over `serve-static` is explained by **not** relying on the file system for existence checks on every request. These are expensive interactions and must be avoided whenever possible! Instead, when not in "dev" mode, `sirv` performs all its file-system operations upfront and then relies on its cache for future operations.
This middleware will work out of the box for [Polka](https://github.com/lukeed/polka), Express, and other Express-like frameworks. It will also work with the native `http`, `https` and `http2` modules. It requires _very_ little effort to modify/wrap it for servers that don't accept the `(req, res, next)` signature.
:bulb: For a feature-complete CLI application, check out the sibling [`sirv-cli`](https://github.com/lukeed/sirv/tree/master/packages/sirv-cli) package as an alternative to [`zeit/serve`](https://github.com/zeit/serve)~!
## Install
```
$ npm install --save sirv
```
## Usage
```js
const sirv = require('sirv');
const polka = require('polka');
const compress = require('compression')();
// Init `sirv` handler
const assets = sirv('public', {
maxAge: 31536000, // 1Y
immutable: true
});
polka()
.use(compress, assets)
.use('/api', require('./api'))
.listen(3000, err => {
if (err) throw err;
console.log('> Ready on localhost:3000~!');
});
```
## API
### sirv(dir, opts={})
Returns: `Function`
The returned function is a middleware in the standard Express-like signature: `(req, res, next)`, where `req` is the [`http.IncomingMessage`](https://nodejs.org/api/http.html#http_class_http_incomingmessage), `res` is the [`http.ServerResponse`](https://nodejs.org/dist/latest-v9.x/docs/api/http.html#http_class_http_serverresponse), and `next` (in this case) is the function to call if no file was found for the given path.
When defined, a `next()` callback is always called _instead of_ the [`opts.onNoMatch`](#optsonnomatch) callback. However, unlike `onNoMatch`, your `next()` is given no arguments.
#### dir
Type: `String`<br>
Default: `.`
The directory from which to read and serve assets. It is resolved to an absolute path &mdash; you must provide an absolute path yourself if `process.cwd()` is not the correct assumption.
#### opts.dev
Type: `Boolean`<br>
Default: `false`
Enable "dev" mode, which disables/skips caching. Instead, `sirv` will traverse the file system ***on every request***.
Additionally, `dev` mode will ignore `maxAge` and `immutable` as these options generate a production-oriented `Cache-Control` header value.
> **Important:** Do not use `dev` mode in production!
#### opts.etag
Type: `Boolean`<br>
Default: `false`
Generate and attach an `ETag` header to responses.
> **Note:** If an incoming request's [`If-None-Match` header](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/If-None-Match) matches the `ETag` value, a `304` response is given.
#### opts.dotfiles
Type: `Boolean`<br>
Default: `false`
Allow requests to dotfiles (files or directories beginning with a `.`).
> **Note:** Requests to [`/.well-known/*`](https://tools.ietf.org/html/rfc8615) are always allowed.
#### opts.extensions
Type: `Array<String>`<br>
Default: `['html', 'htm']`
The file extension fallbacks to check for if a pathame is not initially found. For example, if a `/login` request cannot find a `login` filename, it will then look for `login.html` and `login.htm` before giving up~!
> **Important:** Actually, `sirv` will **also** look for `login/index.html` and `login/index.htm` before giving up.
#### opts.gzip
Type: `Boolean`<br>
Default: `false`
Determine if `sirv` look for **precompiled** `*.gz` files.<br>
Must be enabled _and_ the incoming request's [`Accept Encoding`](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Accept-Encoding) must include "gzip" in order for `sirv` to search for the gzip'd alternative.
> **Note:** The `.gz` assumption also applies to the `opts.extensions` list.
```js
// NOTE: PSEUDO CODE
// Showing lookup logic
// Request: [Accept-Encoding: gzip] "/foobar.jpg"
lookup([
'/foobar.jpg.gz', '/foobar.jpg',
'/foobar.jpg.html.gz', '/foobar.jpg/index.html.gz',
'/foobar.jpg.htm.gz', '/foobar.jpg/index.htm.gz',
'/foobar.jpg.html', '/foobar.jpg/index.html',
'/foobar.jpg.htm', '/foobar.jpg/index.htm',
]);
// Request: [Accept-Encoding: gzip] "/"
lookup([
'/index.html.gz',
'/index.htm.gz',
'/index.html',
'/index.htm',
]);
```
#### opts.brotli
Type: `Boolean`<br>
Default: `false`
Determine if `sirv` look for **precompiled** `*.br` files.<br>
Must be enabled _and_ the incoming request's [`Accept Encoding`](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Accept-Encoding) must include either "br" or "brotli" in order for `sirv` to search for the brotli-compressed alternative.
> **Note:** The `.br` assumption also applies to the `opts.extensions` list.
When both `opts.broli` and `opts.gzip` are enabled &mdash; and all conditions are equal &mdash; then the brotli variant always takes priority.
```js
// NOTE: PSEUDO CODE
// Showing lookup logic
// Request: [Accept-Encoding: br] "/foobar.jpg"
lookup([
'/foobar.jpg.br', '/foobar.jpg',
'/foobar.jpg.html.br', '/foobar.jpg/index.html.br',
'/foobar.jpg.htm.br', '/foobar.jpg/index.htm.br',
'/foobar.jpg.html', '/foobar.jpg/index.html',
'/foobar.jpg.htm', '/foobar.jpg/index.htm',
]);
// Request: [Accept-Encoding: br,gz] "/"
lookup([
'/index.html.br'
'/index.htm.br'
'/index.html.gz'
'/index.htm.gz'
'/index.html'
'/index.htm'
]);
```
#### opts.maxAge
Type: `Number`<br>
Default: `undefined`
Enables the `Cache-Control` header on responses and sets the `max-age` value (in seconds).<br>
For example, `maxAge: 31536000` is equivalent to one year.
#### opts.immutable
Type: `Boolean`<br>
Default: `false`
Appends the [`immutable` directive](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Cache-Control#Revalidation_and_reloading) on your `Cache-Control` header, used for uniquely-named assets that will not change!
> **Important:** Will only work if `opts.maxAge` has a value defined!
#### opts.single
Type: `Boolean` or `String`<br>
Default: `false`
Treat the directory as a single-page application.
When `true`, the directory's index page (default `index.html`) will be sent if the request asset does not exist.<br>
You may pass a `string` value to use a file _instead of_ `index.html` as your fallback.
For example, if "/about" is requested but no variants of that file exist, then the response for "/" is sent instead:
```js
// Note: This is psuedo code to illustrate what's happening
// Request: "/about"
let file = find(['/about', '/about.html', '/about.htm', '/about/index.html', '/about.htm']);
if (file) {
send(file);
} else if (opts.single === true) {
file = find(['/', '/index.html', '/index.htm']);
send(file);
} else if (typeof opts.single === 'string') {
file = find([opts.single]);
send(file);
} else {
// next() or 404
}
```
#### opts.ignores
Type: `false` or `Array<String | RegExp>`
Specify paths/patterns that should ignore the fallback behavior that `opts.single` provides.
By default, any asset-like path (URLs that end with an extension) will be ignored. This means that, for example, if `/foobar.jpg` is not found, a `404` response is sent instead of the `index.html` fallback.
Additionally, any `/.well-known/*` pathname ignores the fallback as do all other dotfile requests when `opts.dotfiles` is enabled.
Any string value(s) will be passed through `new RegExp(value, 'i')` directly.
Finally, you may set `ignores: false` to disable ***all*** ignores, including the defaults. Put differently, this will fallback ***all*** unknown pathnames to your `index.html` (or custom `opts.single` value).
> **Important:** Only has an effect if `opts.single` is enabled.
#### opts.onNoMatch
Type: `Function`
A custom function to run if a file cannot be found for a given request. <br>By default, `sirv` will send a basic `(404) Not found` response.
The function receives the current `req <IncomingMessage>, res <ServerResponse>` pair for as its two arguments.
> **Note:** This won't run if a `next` callback has been provided to the middleware; see [`sirv`](#sirvdir-opts) description.
#### opts.setHeaders
Type: `Function`
A custom function to append or change any headers on the outgoing response. There is no default.
Its signature is `(res, pathname, stats)`, where `res` is the `ServerResponse`, `pathname` is incoming request path (stripped of queries), and `stats` is the file's result from [`fs.statSync`](https://nodejs.org/api/fs.html#fs_fs_statsync_path).
## License
MIT © [Luke Edwards](https://lukeed.com)