A Clojure library for the circuit breaker pattern:
http://en.wikipedia.org/wiki/Circuit_breaker_design_pattern
Add the dependency from https://clojars.org/circuit-breaker to your project.clj file
[circuit-breaker "0.1.8"];; If it errors more than 2 times stop trying the *thing* until 30 seconds have passed
(defncircuitbreaker :memcache {:timeout 30 :threshold 2})
;; Run function, returning `nil` if :memcache is already tripped
(wrap-with-circuit-breaker :memcache (fn [] do-something-that-might-exception))
;; Run function, returning result of (fn [] do-thing-when-tripped) if already tripped
(wrap-with-circuit-breaker :memcache (fn [] do-something-that-might-exception) (fn [] do-thing-when-tripped))
;; Testing a circuit outside of the wrap-with-circuit-breaker
(with-circuit-breaker :memcache {:connected (fn [] "ok") :tripped (fn [] "panic")})Tested against:
- openjdk7
- oraclejdk7
Clojure versions:
- Clojure 1.4
- Clojure 1.5
- Clojure 1.6
- Clojure 1.7
- Clojure 1.8
(The MIT License)
Copyright (c) 2014-current Joseph Wilk
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
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