@adraffy/ens-normalize

What is @adraffy/ens-normalize?

@adraffy/ens-normalize is an npm package designed to normalize Ethereum Name Service (ENS) names. It ensures that ENS names are in a consistent format, which is crucial for avoiding ambiguities and ensuring compatibility across different systems.

What are @adraffy/ens-normalize's main functionalities?

Normalization

This feature allows you to normalize an ENS name to ensure it is in a consistent format. The code sample demonstrates how to normalize the ENS name 'example.eth'.

const { normalize } = require('@adraffy/ens-normalize');
const normalized = normalize('example.eth');
console.log(normalized);

Validation

This feature allows you to validate an ENS name to check if it conforms to the expected format. The code sample demonstrates how to validate the ENS name 'example.eth'.

const { validate } = require('@adraffy/ens-normalize');
const isValid = validate('example.eth');
console.log(isValid);

Unicode Handling

This feature allows you to convert Punycode-encoded ENS names to their Unicode equivalents. The code sample demonstrates how to convert the Punycode-encoded ENS name 'xn--exmple-cua.eth' to its Unicode equivalent.

const { toUnicode } = require('@adraffy/ens-normalize');
const unicodeName = toUnicode('xn--exmple-cua.eth');
console.log(unicodeName);

Other packages similar to @adraffy/ens-normalize

eth-ens-namehash

The eth-ens-namehash package is another tool for generating ENS namehashes. It includes some basic normalization features but is primarily focused on the namehashing process. It is less comprehensive in normalization compared to @adraffy/ens-normalize.

punycode

The punycode package provides utilities for converting between Unicode and Punycode, which is useful for handling internationalized domain names (IDNs). While it does not specifically target ENS names, it can be used in conjunction with other packages to handle Unicode normalization.

README

ens-normalize.js

0-dependancy Compact ES6 Ethereum Name Service (ENS) Name Normalizer that works in the browser.

• Follows ENS Name Normalization Standard
• Passes 100% Validation Tests
• Custom NFC Implementation (or use native)
  • Passes 100% Unicode 15.0.0 Normalization Tests
• Minified File Sizes:
  • 27KB — native NFC via nf-native.js using String.normalize()
  • 35KB Default — custom NFC via nf.js
  • 41KB Everything! — custom NFC + sub-libraries: parts.js, utils.js
• Resolver Demo
• Character Viewer
• List of Supported Emoji
• Confused Explainer

import {ens_normalize} from '@adraffy/ens-normalize';
// npm i @adraffy/ens-normalize
// browser: https://cdn.jsdelivr.net/npm/@adraffy/ens-normalize@latest/dist/index.min.js

// *** ALL errors throw by this library are safe to print ***

// string -> string
// throws on invalid names
// output ready for namehash
let normalized = ens_normalize('RaFFY🚴‍♂️.eTh');
// => "raffy🚴‍♂.eth"

// note: does not enforce .eth TLD 3-character minimum

Format names with fully-qualified emoji:

// works like ens_normalize
// output ready for display
let pretty = ens_beautify('1⃣2⃣.eth'); 
// => "1️⃣2️⃣.eth"

// note: normalization is unchanged:
// ens_normalize(ens_beautify(x)) == ens_normalize(x)

Normalize name fragments for substring search:

// these fragments fail ens_normalize() due to positional rules
// but will normalize fine as fragments
let frag1 = ens_normalize_fragment('AB--');
let frag2 = ens_normalize_fragment('\u{303}');

Input-based tokenization:

// string -> Token[]
// never throws
let tokens = ens_tokenize('_R💩\u{FE0F}a\u{FE0F}\u{304}\u{AD}./');
// [
//     { type: 'valid', cp: 95 },     // valid
//     {                              // (eg. no combining marks)
//         type: 'mapped', 
//         cp: 82,         // input
//         cps: [ 114 ]    // output
//     }, 
//     { 
//         type: 'emoji',
//         input: Emoji(2) [ 128169, 65039 ],  // input 
//         emoji: [ 128169, 65039 ],           // fully-qualified
//         cps: Emoji(1) [ 128169 ]            // output
//     },
//     {
//         type: 'nfc',
//         input: [ 97, 772 ],  // input (before nfc, only valid or mapped)
//         cps: [ 257 ],        // output (after nfc)
//         tokens: [            // tokens (before nfc)
//             { type: 'valid', cps: [ 97 ] },
//             { type: 'ignored', cp: 65039 },
//             { type: 'valid', cps: [ 772 ] }
//         ]
//     },
//     { type: 'ignored', cp: 173 },
//     { type: 'stop', cp: 46 },
//     { type: 'disallowed', cp: 47 }
// ]

// note: if name is normalizable, then:
// ens_normalize(ens_tokenize(name).map(token => {
//     ** convert valid/mapped/nfc/stop to string **
// }).join('')) == ens_normalize(name)

Output-based tokenization:

// string -> Label[]
// never throws
let labels = ens_split('💩Raffy.eth_');
// [
//   {
//     input: [ 128169, 82, 97, 102, 102, 121 ],  
//     offset: 0, // index of codepoint, not substring index!
//                // (corresponding length can be inferred from input)
//     tokens: [
//       Emoji(2) [ 128169, 65039 ],   // emoji
//       [ 114, 97, 102, 102, 121 ]    // nfc-text
//     ],
//     output: [ 128169, 114, 97, 102, 102, 121 ],
//     emoji: true,
//     type: 'Latin'
//   },
//   {
//     input: [ 101, 116, 104, 95 ],
//     offset: 7,
//     tokens: [ [ 101, 116, 104, 95 ] ],
//     output: [ 101, 116, 104, 95 ],
//     emoji: false,
//     error: Error('underscore only allowed at start')
//   }
// ]

Generate a sorted array of supported emoji codepoints:

// () -> number[][]
console.log(ens_emoji());
// [
//     [ 2764 ],
//     [ 128169, 65039 ],
//     [ 128105, 127997, 8205, 9877, 65039 ],
//     ...
// ]

Determine if a character shouldn't be printed directly:

// number -> bool
console.log(should_escape(0x202E)); // eg. RIGHT-TO-LEFT OVERRIDE => true

Determine if a character is a printable combining mark:

// number -> bool
console.log(is_combining_mark(0x20E3)); // eg. COMBINING ENCLOSING KEYCAP => true

Build

• git clone this repo, then npm install
• Follow instructions in /derive/ to generate data files
  • npm run derive
    • spec.json
    • nf.json
    • nf-tests.json
• npm run make — compress data files from /derive/output/
  • include-ens.js
  • include-nf.js
• Follow instructions in /validate/ to generate validation tests
  • npm run validate
    • tests.json
• npm run test — perform validation tests
• npm run build — create /dist/
• npm run rebuild — run all the commands above
• npm run order — create optimal ordering and rebuild again