Add callback functions for instrumentation

src/taoensso/carmine.clj

@@ -79,7 +79,16 @@
   (wcar {} (echo 1) (println (with-replies (ping))) (echo 2))
   (wcar {} (echo 1) (println (with-replies :as-pipeline (ping))) (echo 2))
   (def setupf (fn [_] (println "boo")))
-  (wcar {:spec {:conn-setup-fn setupf}}))
+  (wcar {:spec {:conn-setup-fn setupf}})
+
+  (def conn-close-fn (fn [{spec :spec}] (println spec)))
+  (wcar {:spec {:conn-close-fn conn-close-fn}})
+
+  (def conn-open-fn (fn [{spec :spec}] (println spec)))
+  (wcar {:spec {:conn-open-fn conn-open-fn}})
+
+  (def conn-error-fn (fn [{spec :spec ex :ex}] (println ex)))
+  (wcar {:spec {:conn-error-fn conn-error-fn}}))
 
 (comment
   (wcar {}

src/taoensso/carmine/connections.clj

@@ -36,8 +36,13 @@
           (protocol/with-context this
             (protocol/with-replies
               (taoensso.carmine/ping)))
-          (catch Exception _)))))
-  (close-conn [_] (.close socket)))
+          (catch Exception ex
+             (if-let [conn-error-fn (:conn-error-fn spec)]
+               (conn-error-fn {:spec spec :ex ex})))))))
+  (close-conn [_]
+    (if-let [conn-close-fn (:conn-close-fn spec)]
+      (conn-close-fn {:spec spec}))
+    (.close socket)))
 
 (defprotocol IConnectionPool
   (get-conn     [this spec])
@@ -100,6 +105,9 @@
 
         db (when (and db (not (zero? db))) db)]
 
+    (if-let [conn-open-fn (:conn-open-fn spec)]
+      (conn-open-fn {:spec spec}))
+
     (when (or password db conn-setup-fn)
       (protocol/with-context conn
         (protocol/with-replies ; Discard replies
@@ -150,12 +158,16 @@
     :test-while-idle? (.setTestWhileIdle pool v) ; false
     :time-between-eviction-runs-ms (.setTimeBetweenEvictionRunsMillis pool v) ; -1
 
+    :pool-create-fn ()
+
     (throw (ex-info (str "Unknown pool option: " k) {:option k})))
   pool)
 
 (def conn-pool
   (enc/memoize_
     (fn [pool-opts]
+      (if-let [pool-create-fn (:pool-create-fn pool-opts)]
+        (pool-create-fn {:pool pool-opts}))
       (cond
         (identical? pool-opts :none) (->NonPooledConnectionPool)
         ;; Pass through pre-made pools (note that test reflects):

test/taoensso/carmine/tests/main.clj

@@ -12,7 +12,32 @@
   (remove-ns      'taoensso.carmine.tests.main)
   (test/run-tests 'taoensso.carmine.tests.main))
 
-(defmacro wcar* [& body] `(car/wcar {:pool {} :spec {}} ~@body))
+(defn conn-setup [_]
+  (car/client-setname "the-name"))
+
+(defn conn-error [{spec :spec ex :ex}]
+  (let [tags {:redis-host (:host spec)
+              :redis-port (:port spec)
+              :redis-db (:db spec)}]))
+
+(defn conn-close [{spec :spec}]
+  (let [tags {:redis-host (:host spec)
+              :redis-port (:port spec)
+              :redis-db (:db spec)}]))
+
+(defn conn-open [{spec :spec}]
+  (let [tags {:redis-host (:host spec)
+              :redis-port (:port spec)
+              :redis-db (:db spec)}]))
+
+(defn pool-create [{pool :pool}])
+
+(defmacro wcar* [& body] `(car/wcar {:pool {:pool-create-fn pool-create}
+                                     :spec {:conn-setup-fn conn-setup
+                                            :conn-error-fn conn-error
+                                            :conn-close-fn conn-close
+                                            :conn-open-fn conn-open}} ~@body))
+
 (def tkey (partial car/key :carmine :temp :test))
 (defn clean-up-tkeys! [] (when-let [ks (seq (wcar* (car/keys (tkey :*))))]
                            (wcar* (apply car/del ks))))