jed · October 6, 2023 02:56
diff --git a/mimedb.js b/mimedb.js
 /*

 This script runs a Deno server that serves an html page that
 uses the the Origin Private File System API to determine which
 mime type a browser infers based on file extension. It uses
 the mime-db database to enumerate all candidate extensions.

 For background, see https://mastodon.social/@jed/110533898437100502

 1. Run deno run -A --watch mimedb.js
 2. Open http://localhost:8000 in Chrome, Edge, Safari, and Firefox
 3. Check the last downloaded CSV for the results.

 */

 import db from 'https://esm.sh/mime-db'

 let data = [
 	['extension', 'mimedb', 'edg', 'chrome', 'safari', 'firefox']
 ]

 let map = new Map()
 for (let [type, {extensions = []}] of Object.entries(db)) {
 	for (let extension of extensions) map.set(extension, type)
 }

 data.push(...map)

 let onload = async () => {
 	let dir = await navigator.storage.getDirectory()
 	let form = document.forms[0]
 	for (let element of form.elements) try {
 		let handle = await dir.getFileHandle(`test.${element.name}`, {create: true})
 		let {name, type} = await handle.getFile()
 		element.value = type
 		dir.removeEntry(name)
 	} catch (e) {}

 	form.submit()
 }

 Deno.serve(async request => {
 	if (request.method === 'POST') {
 		let header = request.headers.get('user-agent')
 		let index = data[0].findIndex(a => RegExp(a, 'i').test(header))
 		let formData = await request.formData()
 		for (let [ext, type] of formData) {
 			data.find(r => r[0] === ext)[index] = type
 		}

 		let csv = data.reduce((a, b) => `${a}\n${b.join(',')}`)
 		return new Response(csv, {headers: {'content-type': 'text/csv'}})
 	}

 	let inputs = data.slice(1).map(r => `<input type=hidden name=${r[0]}>`).join('')
 	let html = `<form method=post>${inputs}</form><script>onload=${onload}</script>`
 	return new Response(html, {headers: {'content-type': 'text/html'}})
 })
diff --git a/results.csv b/results.csv
	/*

	This script runs a Deno server that serves an html page that
	uses the the Origin Private File System API to determine which
	mime type a browser infers based on file extension. It uses
	the mime-db database to enumerate all candidate extensions.

	For background, see https://mastodon.social/@jed/110533898437100502

	1. Run deno run -A --watch mimedb.js
	2. Open http://localhost:8000 in Chrome, Edge, Safari, and Firefox
	3. Check the last downloaded CSV for the results.

	*/

	import db from 'https://esm.sh/mime-db'

	let data = [
	['extension', 'mimedb', 'edg', 'chrome', 'safari', 'firefox']
	]

	let map = new Map()
	for (let [type, {extensions = []}] of Object.entries(db)) {
	for (let extension of extensions) map.set(extension, type)
	}

	data.push(...map)

	let onload = async () => {
	let dir = await navigator.storage.getDirectory()
	let form = document.forms[0]
	for (let element of form.elements) try {
	let handle = await dir.getFileHandle(`test.${element.name}`, {create: true})
	let {name, type} = await handle.getFile()
	element.value = type
	dir.removeEntry(name)
	} catch (e) {}

	form.submit()
	}

	Deno.serve(async request => {
	if (request.method === 'POST') {
	let header = request.headers.get('user-agent')
	let index = data[0].findIndex(a => RegExp(a, 'i').test(header))
	let formData = await request.formData()
	for (let [ext, type] of formData) {
	data.find(r => r[0] === ext)[index] = type
	}

	let csv = data.reduce((a, b) => `${a}\n${b.join(',')}`)
	return new Response(csv, {headers: {'content-type': 'text/csv'}})
	}

	let inputs = data.slice(1).map(r => `<input type=hidden name=${r[0]}>`).join('')
	let html = `<form method=post>${inputs}</form><script>onload=${onload}</script>`
	return new Response(html, {headers: {'content-type': 'text/html'}})
	})
No results found