Toggle log level during testing

log_test.clj

(ns log-test
  (:import
   [ch.qos.logback.classic Level]
   [org.slf4j LoggerFactory Logger]))

(defn set-log-level
  [logger level]
  (.setLevel logger level))

(defn root-logger []
  (LoggerFactory/getLogger Logger/ROOT_LOGGER_NAME))

(defn with-log-level*
  [level f]
  (let [new-level# (Level/valueOf (name level))
        logger#    (root-logger)
        old-level# (.getLevel logger#)]
    (set-log-level logger# new-level#)
    (try
      (f)
      (finally
        (set-log-level logger# old-level#)))))

(defmacro with-log-level
  "Runs the body with the loglevel set to the given level"
  [level & body]
  `(with-log-level* ~level (fn [] ~@body)))