soncodi / shortid

Short id generator. Url-friendly. Non-predictable. Cluster-compatible.

ShortId

ShortId creates amazingly short non-sequential url-friendly unique ids. Perfect for url shorteners, MongoDB and Reddis ids, and any other id users might see.

• By default 7-14 url-friendly characters: A-Z, a-z, 0-9, _-
• Non-sequential so they are not predictable.
• Supports cluster (automatically), custom seeds, custom alphabet.
• Can generate any number of ids without duplicates, even millions per day.
• Perfect for games, especially if you are concerned about cheating so you don't want an easily guessable id.
• Apps can be restarted any number of times without any chance of repeating an id.
• Popular replacement for Mongo ID/Mongoose ID.
• Includes Mocha tests.

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Install

$ npm install shortid --save

shortid has no dependencies.

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Usage

var shortId = require('shortid');

console.log(shortId.generate());

//PPBqWA9

Mongoose Unique Id

_id: {
    type: String,
    unique: true,
    'default': shortId.generate
},

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Example

~/projects/shortid ❯ node examples/examples.js
eWRhpRV
23TplPdS
46Juzcyx
dBvJIh-H
2WEKaVNO
7oet_d9Z
dogPzIz8
nYrnfYEv
a4vhAoFG
hwX6aOr7

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API

generate()

Returns an amazingly short non-sequential unique id.

Alias: shortId()

Example

users.insert({
    _id: shortId.generate()
    name: ...
    email: ...
    });

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seed(float)

Default: 1

Optional

Choose a unique value that will seed the random number generator so users won't be able to figure out the pattern of the unique ids. Call it just once in your application before using shortId and always use the same value in your application.

Most developers won't need to use this, it's mainly for testing ShortId.

If you are worried about users somehow decrypting the id then use it as a secret value for increased encryption.

Example

shortId.seed(1000);

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characters(string)

Default: '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ-_'

Optional

Change the characters used.

You must provide a string of all 64 unique characters. Order is not important.

The default characters provided were selected because they are url safe.

Example

// use $ and @ instead of - an _
shortId.characters('0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ$@');

// any 64 unicode charcters work
shortId.characters('ⒶⒷⒸⒹⒺⒻⒼⒽⒾⒿⓀⓁⓂⓃⓄⓅⓆⓇⓈⓉⓊⓋⓌⓍⓎⓏⓐⓑⓒⓓⓔⓕⓖⓗⓘⓙⓚⓛⓜⓝⓞⓟⓠⓡⓢⓣⓤⓥⓦⓧⓨⓩ①②③④⑤⑥⑦⑧⑨⑩⑪⑫');

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Some projects using shortId

shortId was created for Node Knockout 2011 winner for Most Fun Doodle Or Die. Millions of doodles have been saved with shortId filenames. Every log message gets a shortId to make it easy for us to look up later.

Here are some other projects that use shortId:

• bevy - A simple server to manage multiple Node services.
• capre - Cross-Server Data Replication.
• cordova-build - an alternative to phonegap build that runs on your servers/agents.
• couchdb-tools - A library of handy functions for use when working with CouchDB documents.
• CleverStack/clever-email - E-mail system for CleverStack.
• CloudTypes - JavaScript end2end implementation of the Cloud Types model for Eventual Consistency programming.
• dnode-tarantula - an asynchronous rpc and event system for node.js based on dnode-protocol and TCP sockets.
• mongoose-url-shortener - A simple URL Shortening library for NodeJS using Promises/A+ results.
• mozilla/smokejumper - The Smoke Jumper project is an effort to bring dead simple, secure, P2P file sharing to Firefox.
• shortness - Node based URL shortener that uses SQLite.
• file-db - Document database that uses directories and files to store its data, supporting nested key-value objects in named collections.
• resume-generator - Resume Generator.
• riffmint - Collaboration in musical space.
• rap1ds/dippa - Dippa Editor – A web-based LaTeX editor

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License

(The MIT License)

Copyright (c) 2011-2014 Dylan Greene [email protected]

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.