A cross-platform bloom filter implemented in Clojure(Script).
Include the following dependency in project.clj file:
:dependencies [[davidwclin/cljc-bloom "0.1.1"]]
(require '[bloom.core :as bf])
(let [upper-cardinality 20
target-false-positive-rate 0.05]
(def my-bf
(bf/->bf upper-cardinality target-false-positive-rate)))
(doseq [i (range 10)]
(bf/add! my-bf (str i)))
(bf/has? my-bf "4") ;; true
(bf/has? my-bf "45") ;; false(de)serialization into (or from) JSON
;; serialize in clj
(bf/serialize my-bf "/tmp/my-bf.json")
;; deserialize in clj
(require '[clojure.data.json :as json])
(def my-bf
(-> "/tmp/my-bf.json" slurp json/read-str bf/->bf))
(bf/has? my-bf "4") ;; true
(bf/has? my-bf "45") ;; false
;; deserialize in cljs
;; retrieve serialized bf from server. Using just the file content as an example here.
(let [serialized-string "{\"buckets-\":[174137362,276431338,1342183560,-1029155791],\"seed\":8461509,\"m\":128,\"k\":5}"]
(def my-bf
(-> serialized-string js/JSON.parse bf/->bf)))
(bf/has? my-bf "4") ;; true
(bf/has? my-bf "45") ;; false- Bloom filters require an arbitrary number of hashes, this is achieved by generating linear combinations of two xxHashes.
- Javscript bitwise ops are 32 bits, so the same is done on the Java side for compatibility.
- cljs - run in cursive
- clj - run as usual
Copyright © 2017 @davidwclin
Distributed under the Eclipse Public License either version 1.0 or (at your option) any later version.