Clojure macro to capture log4j2 ThreadContexts

logmacro.clj

;; Originally dual licensed under EPL 1.0 and AGPL 3.

(import 'org.apache.logging.log4j.ThreadContext)

(defn capture-logging-context []
  (into {} (ThreadContext/getContext)))

;; Modified from withdrawn library:
;; https://github.com/malcolmsparks/clj-logging-config/blob/master/src/main/clojure/clj_logging_config/log4j.clj
(defmacro with-logging-context [x & body]
  `(let [x# ~x
         ctx# (capture-logging-context)]
     (try
       (if (map? x#)
         (run! (fn [[k# v#]]
                 (when-not (nil? v#)
                   (ThreadContext/put (name k#) (str v#)))) x#)
         (ThreadContext/push (str x#)))
       ~@body
       (finally
        (if (map? x#)
          (run! (fn [[k# v#]]
                  (ThreadContext/remove (name k#))
                  (when-let [old# (get ctx# (name k#))]
                    (ThreadContext/put (name k#) (str old#)))) x#)
          (ThreadContext/pop))))))