{"id":20620526,"url":"https://github.com/fern-flower-lab/leveldb-clj","last_synced_at":"2026-02-03T00:11:50.692Z","repository":{"id":58200631,"uuid":"530375737","full_name":"fern-flower-lab/leveldb-clj","owner":"fern-flower-lab","description":"The LevelDB driver for Clojure","archived":false,"fork":false,"pushed_at":"2022-10-22T11:18:51.000Z","size":12,"stargazers_count":3,"open_issues_count":0,"forks_count":1,"subscribers_count":1,"default_branch":"master","last_synced_at":"2025-06-17T07:07:19.347Z","etag":null,"topics":["binary-storage","clojure","clojure-library","inmemory-db","kv-store","ledger","leveldb","tiny-library","transactional"],"latest_commit_sha":null,"homepage":"","language":"Clojure","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":"mit","status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/fern-flower-lab.png","metadata":{"files":{"readme":"README.adoc","changelog":null,"contributing":null,"funding":null,"license":"LICENSE","code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null}},"created_at":"2022-08-29T20:04:14.000Z","updated_at":"2022-12-12T23:19:55.000Z","dependencies_parsed_at":"2022-09-06T08:10:15.613Z","dependency_job_id":null,"html_url":"https://github.com/fern-flower-lab/leveldb-clj","commit_stats":null,"previous_names":[],"tags_count":5,"template":false,"template_full_name":null,"purl":"pkg:github/fern-flower-lab/leveldb-clj","repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/fern-flower-lab%2Fleveldb-clj","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/fern-flower-lab%2Fleveldb-clj/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/fern-flower-lab%2Fleveldb-clj/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/fern-flower-lab%2Fleveldb-clj/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/fern-flower-lab","download_url":"https://codeload.github.com/fern-flower-lab/leveldb-clj/tar.gz/refs/heads/master","sbom_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/fern-flower-lab%2Fleveldb-clj/sbom","host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":263441000,"owners_count":23467024,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2022-07-04T15:15:14.044Z","host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":["binary-storage","clojure","clojure-library","inmemory-db","kv-store","ledger","leveldb","tiny-library","transactional"],"created_at":"2024-11-16T12:14:46.076Z","updated_at":"2026-02-03T00:11:50.686Z","avatar_url":"https://github.com/fern-flower-lab.png","language":"Clojure","funding_links":[],"categories":[],"sub_categories":[],"readme":"= leveldb-clj\n\nA Clojure tiny and low-level library to handle key-value store at LevelDB for blockchain projects.\n\nimage:https://img.shields.io/github/license/fern-flower-lab/leveldb-clj?style=for-the-badge[GitHub]\nimage:https://img.shields.io/clojars/v/ai.z7/leveldb-clj.svg?style=for-the-badge[]\nimage:https://img.shields.io/github/v/tag/fern-flower-lab/leveldb-clj?style=for-the-badge[GitHub tag (latest by date)]\nimage:https://img.shields.io/github/last-commit/fern-flower-lab/leveldb-clj?style=for-the-badge[GitHub last commit]\nimage:https://img.shields.io/github/v/release/fern-flower-lab/leveldb-clj?style=for-the-badge[GitHub release (latest by date)]\n\n== Usage\n\n.leiningen project.clj\n[source,clojure]\n----\n...\n :dependencies [[org.clojure/clojure \"1.11.1\"]\n...\n                [ai.z7/leveldb-clj \"0.0.6\"]]\n...\n----\n\nand then\n\n[source,clojure]\n----\n(ns my.application.ns\n  (:require [leveldb-clj.core :as leveldb]\n            [leveldb-clj.kv :as kv]\n            [leveldb-clj.tx :as tx]))\n\n;; regular interface designed for generic kv/* methods\n(defonce ^:private store\n  (leveldb/map-\u003eLevelDBStore {:path \"mystore.level.db\"}))\n\n;; atomic interface designed for transactional tx/* methods\n(defonce ^:private atomic-store\n  (tx/-\u003eLevelDB-TX store (atom {})))\n----\n\nThat is - the store is ready!\n\n=== Resource Management\n\nThe store implements `java.io.Closeable`. Always close the store when done:\n\n[source, clojure]\n----\n;; Using with-open for automatic cleanup\n(with-open [store (leveldb/map-\u003eLevelDBStore {:path \"mystore.level.db\"})]\n  (kv/insert store (.getBytes \"key\") (.getBytes \"value\"))\n  (kv/retrieve store (.getBytes \"key\")))\n\n;; Or manually close when done\n(.close store)\n----\n\nThe `stream` function also returns a `Closeable` sequence. Use `with-open` when iterating:\n\n[source, clojure]\n----\n(with-open [s (kv/stream store)]\n  (doseq [entry s]\n    (println (String. (.getKey entry)))))\n----\n\nNote: `list-keys` handles closing automatically.\n\n=== Generic interface\n\n[source, clojure]\n----\ntest=\u003e (def store (leveldb/map-\u003eLevelDBStore {:path \"mystore.level.db\"}))\n\ntest=\u003e (kv/insert store (.getBytes \"eee\") (.getBytes \"fff\"))\n; #leveldb_clj.core.LevelDBStore{:db #object[org.iq80.leveldb.impl.DbImpl 0x69957a8 \"org.iq80.leveldb.impl.DbImpl@69957a8\"], :codec nil}\n\ntest=\u003e (kv/list-keys store)\n; (#object[\"[B\" 0x72b795cf \"[B@72b795cf\"])\n\ntest=\u003e (map #(String. %) (kv/list-keys store))\n; (\"eee\")\n\ntest=\u003e (kv/retrieve store (.getBytes \"eee\"))\n; #object[\"[B\" 0x453ad576 \"[B@453ad576\"]\n\ntest=\u003e (String. (kv/retrieve store (.getBytes \"eee\")))\n; \"fff\"\n\ntest=\u003e (kv/delete store (.getBytes \"eee\"))\n; #leveldb_clj.core.LevelDBStore{:db #object[org.iq80.leveldb.impl.DbImpl 0x69957a8 \"org.iq80.leveldb.impl.DbImpl@69957a8\"], :codec nil}\n\ntest=\u003e (map #(String. %) (kv/list-keys store))\n; ()\n\ntest=\u003e (String. (kv/retrieve store (.getBytes \"eee\")))\n; Execution error (NullPointerException) at java.lang.String/\u003cinit\u003e (String.java:1460).\n; Cannot invoke \"java.lang.StringBuffer.toString()\" because \"buffer\" is null\n\n----\n\n=== Transactional interface\n\n[source, clojure]\n----\ntest=\u003e (def atomic-store (tx/-\u003eLevelDB-TX store (atom {})))\n\ntest=\u003e (map #(String. %) (kv/list-keys store))\n; ()\ntest=\u003e (tx/add atomic-store (.getBytes \"eee\") (.getBytes \"fff\"))\n; #leveldb_clj.tx.LevelDB-TX{:store #leveldb_clj.core.LevelDBStore{:db #object[org.iq80.leveldb.impl.DbImpl 0x69957a8 \"org.iq80.leveldb.impl.DbImpl@69957a8\"], :codec nil}, :state #object[clojure.lang.Atom 0x3e85d3ce {:status :ready, :val {#object[\"[B\" 0x38381caf \"[B@38381caf\"] #object[\"[B\" 0x4b1aeb91 \"[B@4b1aeb91\"]}}]}\n\ntest=\u003e (map #(String. %) (kv/list-keys store))\n; ()\n\ntest=\u003e (tx/commit atomic-store)\n; #leveldb_clj.tx.LevelDB-TX{:store #leveldb_clj.core.LevelDBStore{:db #object[org.iq80.leveldb.impl.DbImpl 0x69957a8 \"org.iq80.leveldb.impl.DbImpl@69957a8\"], :codec nil}, :state #object[clojure.lang.Atom 0x3e85d3ce {:status :ready, :val {}}]}\ntest=\u003e (map #(String. %) (kv/list-keys store))\n; (\"eee\")\n\n(tx/add atomic-store (.getBytes \"eee\") (.getBytes \"HHH\"))\n; #leveldb_clj.tx.LevelDB-TX{:store #leveldb_clj.core.LevelDBStore{:db #object[org.iq80.leveldb.impl.DbImpl 0xb2e2921 \"org.iq80.leveldb.impl.DbImpl@b2e2921\"], :codec nil}, :state #object[clojure.lang.Atom 0x7d995254 {:status :ready, :val {#object[\"[B\" 0x266702a9 \"[B@266702a9\"] #object[\"[B\" 0x77cfe94e \"[B@77cfe94e\"]}}]}\n\ntest=\u003e (map #(String. %) (kv/list-keys store))\n; (\"eee\")\n\ntest=\u003e (String. (kv/retrieve store (.getBytes \"eee\")))\n; \"fff\"\n\ntest=\u003e (tx/rollback atomic-store)\n; #leveldb_clj.tx.LevelDB-TX{:store #leveldb_clj.core.LevelDBStore{:db #object[org.iq80.leveldb.impl.DbImpl 0xb2e2921 \"org.iq80.leveldb.impl.DbImpl@b2e2921\"], :codec nil}, :state #object[clojure.lang.Atom 0x7d995254 {:status :ready, :val {}}]}\n\ntest=\u003e (String. (kv/retrieve store (.getBytes \"eee\")))\n; \"fff\"\n\ntest=\u003e (tx/add atomic-store (.getBytes \"eee\") (.getBytes \"HHH\"))\n; #leveldb_clj.tx.LevelDB-TX{:store #leveldb_clj.core.LevelDBStore{:db #object[org.iq80.leveldb.impl.DbImpl 0xb2e2921 \"org.iq80.leveldb.impl.DbImpl@b2e2921\"], :codec nil}, :state #object[clojure.lang.Atom 0x7d995254 {:status :ready, :val {#object[\"[B\" 0xe0570d \"[B@e0570d\"] #object[\"[B\" 0x159a9133 \"[B@159a9133\"]}}]}\n\ntest=\u003e (String. (kv/retrieve store (.getBytes \"eee\")))\n\"fff\"\n\ntest=\u003e (tx/commit atomic-store)\n; #leveldb_clj.tx.LevelDB-TX{:store #leveldb_clj.core.LevelDBStore{:db #object[org.iq80.leveldb.impl.DbImpl 0xb2e2921 \"org.iq80.leveldb.impl.DbImpl@b2e2921\"], :codec nil}, :state #object[clojure.lang.Atom 0x7d995254 {:status :ready, :val {}}]}\n\ntest=\u003e (String. (kv/retrieve store (.getBytes \"eee\")))\n; \"HHH\"\n\n----\n\n== License\n\nDistributed under the MIT license.\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Ffern-flower-lab%2Fleveldb-clj","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Ffern-flower-lab%2Fleveldb-clj","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Ffern-flower-lab%2Fleveldb-clj/lists"}