leo-profanity

Profanity filter, based on "Shutterstock" dictionary. Demo page, API document page

Installation

// npm
npm install leo-profanity
npm install leo-profanity --no-optional # install only English bad word dictionary

// yarn
yarn add leo-profanity
yarn add leo-profanity --ignore-optional # install only English bad word dictionary

// Bower
bower install leo-profanity
// dictionary/default.json

// githack
<script src="https://raw.githack.com/jojoee/bahttext/master/src/index.js"></script>
const filter = LeoProfanity
filter.clearList()
filter.add(["boobs", "butt"])

Example usage for npm

// support languages
// - en
// - fr
// - ru

var filter = require('leo-profanity');

// output: I have ****, etc.
filter.clean('I have boob, etc.');

// replace current dictionary with the french
filter.loadDictionary('fr');

// create new dictionary
filter.addDictionary('th', ['หนึ่ง', 'สอง', 'สาม', 'สี่', 'ห้า'])

See more here LeoProfanity - Documentation

Algorithm

This project decide to split it into 2 parts, Sanitize and Filter and these below is a interesting algorithms.

Sanitize

Attempt 1 (1.1): Convert all into lowercase string
Example:
- "SomeThing" to "something"
Advantage:
- Simple to understand
- Simple to implement
Disadvantage or Caution:
- Will ignore "case sensitive" word

Attempt 2 (1.2): Turn "similar-like" symbol to alphabet
Example:
- "@" to "a"
- "5" or "$" to "s"
- "@ss" to "ass"
- "b00b" to "boob"
- "a$$a$$in" to "assassin"
Advantage:
- Detect some trick words
Disadvantage or Caution:
- False positive
- Subjective, which depends on each person think about the symbol
- Limit user imagination (user cannot play with word)
  e.g. "[email protected]"
  e.g. user want to try something funny like "a$$a$$in"

Attempt 3 (1.3): Replace "." and "," with space to separate words
In some sentence, people usually using "." and "," to connect or end the sentence
Example:
- "I like a55,b00b.t1ts" to "I like a55 b00b t1ts"
Advantage:
- Increase founding possibility e.g. "I like a55,b00b.t1ts"
Disadvantage or Caution:
- Disconnect some words e.g. "[email protected]"

Filter

Attempt 1 (2.1): Split into array (or using regex)
Using space to split "word string" into "word array" then check by profanity word list
Example:
- "I like ass boob" to ["I", "like", "ass", "boob"]
Advantage:
- Simple to implement
Disadvantage:
- Need proper list of profanity word
- Some "false positive" e.g. Great tit (https://en.wikipedia.org/wiki/Great_tit)

Attempt 2 (2.2): Filter word inside (with or without space)
Detect all alphabet that contain "profanity word"
Example:
- "thistextisfunnyboobsanda55" which contains suspicious words: "boobs", "a55"
Advantage:
- Can detect "un-spaced" profanity word
Disadvantage:
- Many "false positive" e.g. http://www.morewords.com/contains/ass/, Clbuttic mistake (filter mistake)

In Summary

• We don't know all methods that can produce profanity word (e.g. how many different ways can you enter a55 ?)
• There have a non-algorithm-based approach to achieve it (yet)
• People will always find a way to connect with each other (e.g. Leet)

So, this project decide to go with 1.1, 1.3 and 2.1.

(note - you can found other attempts in "Reference" section)

CMD

npm run test.watch
npm run validate
npm run doc.generate

# test npm publish
npm publish --dry-run

Other languages

• [x] Javascript on npmjs.com/package/leo-profanity
• [x] PHP on packagist.org/packages/jojoee/leo-profanity
• [x] Python on pypi.org/project/leoprofanity
• [ ] Java on Maven
• [ ] Wordpress on wordpress.org

Reference

• Inspired by jwils0n/profanity-filter
• Algorithm / Discussion
  • "similar-like" symbol to alphabet
  • Replace Bad words using Regex
  • Clbuttic
  • The Clbuttic Mistake
  • The Clbuttic Mistake: When obscenity filters go wrong
  • Obscenity Filters: Bad Idea, or Incredibly Intercoursing Bad Idea?
  • How do you implement a good profanity filter?
  • The Untold History of Toontown’s SpeedChat (or BlockChattm from Disney finally arrives)
  • Profanity Filter Performance in Java
• Resource bad-word list
  • Bad words list (458 words) by Alejandro U. Alvarez
  • DansGuardian - dansguardian.org, DansGuardian Phraselists
  • Seven dirty words
  • Shutterstock
  • MauriceButler/badwords
  • http://www.cs.cmu.edu/~biglou/resources/bad-words.txt
• Tool
  • RegExr