jsb
jsbloom
npm i jsbloom
jsb

jsbloom

bloom filter implementation for javascript

by carey

1.1.0 (see all)License:MITTypeScript:Not Found
npm i jsbloom
Readme

#jsbloom

Build Status

A fast bloom filter implementation in JavaScript using the djb2 and sdbm algorithms.

From Less Hashing, Same Performance: Building a Better Bloom Filter by Adam Kirsch et al, it is possible to build k hash values from only 2 unique values. Hence, it is sufficient to have two unique hashes generated.

Usage

var filter = new JSBloom(items, false_probability_chance);

filter.addEntry("xyz");

filter.checkEntry("xyz"); // returns true

filter.checkEntry("yz"); // returns false

Testing

Testing is done with mocha and chai

npm install mocha chai
mocha

Parameters

items: ceiling of entries to add
false_probability_chance: chance of false positives to occur

JSBloom will automatically generate the needed bit array and amount of hashes needed to meet your requirements.

API reference

addEntry(str): adds str to bloom filter
addEntries(arr): iterates over arr and adds every entry within
checkEntry(str): checks if str in filter, returns false if definitely not, true if maybe
importData(base64, [number_of_hashes]): loads a base 64 LZW compressed Uint8Array
exportData(): returns base 64 encoded Uint8Array LZW as string
exportData(callback): returns the base 64 encoded Uint8Array LZW compressed to provided callback

Downloads/wk

5

GitHub Stars

23

LAST COMMIT

6yrs ago

MAINTAINERS

1

CONTRIBUTORS

3

OPEN ISSUES

1

OPEN PRs

0
VersionTagPublished
1.1.0
latest
6yrs ago
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