finite-cache

finite-cache is a Clojure caching library that allows you to limit the size of a cache object.

Requirements

• JDK 1.9+
• You must start the JVM with option -Djdk.attach.allowAttachSelf, otherwise the agent will not be able to dynamically attach to the running process. For Leiningen, add :jvm-opts ["-Djdk.attach.allowAttachSelf"] to project.clj. For Boot, start the process with environment variable BOOT_JVM_OPTIONS="-Djdk.attach.allowAttachSelf".

Usage

(require '[finite-cache.core :refer :all])

(def cache* (finite-cache + {;; when size of the map that holds cache exceeds 300MB, it will be cleared
                               :threshold     [300 :mb]
                               ;; executor that checks map's size every 15 minutes
                               :every         [15 :minutes]
                               ;; (Optional) initial delay before executor starts,
                               ;; since :every's time unit is :minutes, :delay has the same time unit
                               ;; so there is 5 minutes delay
                               :delay         5
                               ;; (Optional) await timeout when shutting down the executor, in milliseconds
                               :await-timeout 1500}))

  (def memoized-fn (memo-fn cache*))

  (memoized-fn 1 2 3)
  ;;=> 6

  (size cache*)
  ;; => 312 (cache's size)

  (cache cache*)
  ;; =>  {[1 2 3] 6} (cache itself)

  (invalidate cache*)
  ;; => {} (clears cache)

  (change-settings cache* {:threshold [1 :gb]
                           :every [2 :hours]})
  ;; => changes cache' options and restarts the executor

  (restart-executor cache*)
  ;; => restarts executor

  (shutdown-executor cache*)
  ;; => shutdowns executor

  (executor-state cache*)
  ;;=> :terminated

License

MIT License

Copyright 2020 Ertuğrul Çetin

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
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The above copyright notice and this permission notice shall be included in all
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