@kakang/abstract-send

The code on this package is based on @fastify/send and ported to TypeScript with some additional features.

Send is a library for streaming files from the file system as an HTTP response supporting partial responses (Ranges), conditional-GET negotiation (If-Match, If-Unmodified-Since, If-None-Match, If-Modified-Since), high test coverage, and granular events which may be leveraged to take appropriate actions in your application or framework.

Installation

$ npm install @kakang/abstract-send

API

var send = require('@fastify/send')

send(req, path, [options])

Provide statusCode, headers and stream for the given path to send to a res. The req is the Node.js HTTP request and the path is a urlencoded path to send (urlencoded, not the actual file-system path).

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 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' Send a 403 for any request for a dotfile.
• 'ignore' Pretend like the dotfile does not exist and 404.

The default value is similar to 'ignore', with the exception that this default will not ignore the files within a directory that begins with a dot, for backward-compatibility.

end

Byte offset at which the stream ends, defaults to the length of the file minus 1. The end is inclusive in the stream, meaning end: 3 will include the 4th byte in the stream.

etag

Enable or disable etag generation, defaults to true.

extensions

If a given file doesn't exist, try appending one of the given extensions, in the given order. By default, this is disabled (set to false). An example value that will serve extension-less HTML files: ['html', 'htm']. This is skipped if the requested file already has an extension.

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 send supports "index.html" files, 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.

root

Serve files relative to path.

start

Byte offset at which the stream starts, defaults to 0. The start is inclusive, meaning start: 2 will include the 3rd byte in the stream.

engine

Provides engine for finding and serving the files.

import { stat } from 'node:fs/promises'
import { createReadStream } from 'node:fs'

// it demonstrates using the built-in file engine
const fsEngine = {
  stat(path) {
    return stat(path)
  },
  createReadStream(path, options) {
    return createReadStream(path, options)
  }
}

import { Readable } from 'node:stream'

// it demonstrates custom one
const customEngine = {
  stat(path) {
    // minimal interface to return
    return {
      size: 1,
      mtime: new Date(),
      isDirectory: () => false
    }
  },
  createReadStream(path, options) {
    // must return readable stream
    // options provide start and end to retrieve partial data
    return Readable.from(['hello', 'world']) 
  }
}

.mime

The mime export is a proxy of global instance of the mime npm module. The methods is transformed to async, to resolve the ESM import on CommonJS environment.

This is used to configure the MIME types that are associated with file extensions as well as other options for how to resolve the MIME type of a file (like the default type to use for an unknown file extension).

.mime.getType(path)

import { mime } from '@kakang/abstract-send'
await mime.getType('package.json')

.mime.getExtension(type)

import { mime } from '@kakang/abstract-send'
await mime.getExtension('application/json')

.mime.getAllExtensions(type)

import { mime } from '@kakang/abstract-send'
await mime.getAllExtensions('application/json')

.mime.define(typeMap, force)

import { mime } from '@kakang/abstract-send'
await mime.define({
  'app/new-extension': ['.app']
}, false)

.mime.default_type

It is the default type used by this package when mime cannot resolve a proper type.

License

MIT