From 3d961a8a5de0130e0e24956520eb738b6e145500 Mon Sep 17 00:00:00 2001
From: liquidz <liquidz.uo@gmail.com>
Date: Thu, 7 Jun 2018 09:59:02 +0900
Subject: [PATCH] Add low-level APIs to allow handing SMTP connection manually

---
 src/postal/smtp.clj | 39 ++++++++++++++++++++++++++++++---------
 1 file changed, 30 insertions(+), 9 deletions(-)

diff --git a/src/postal/smtp.clj b/src/postal/smtp.clj
index b40cf8d..69adb39 100644
--- a/src/postal/smtp.clj
+++ b/src/postal/smtp.clj
@@ -26,14 +26,36 @@
         [postal.support :only [make-props]])
   (:import [javax.mail Transport Session]))
 
+(defn get-session [server]
+  (let [{:keys [sender debug]} server]
+    (doto (Session/getInstance (make-props sender server))
+      (.setDebug (if debug true false)))))
+
+(defn get-protocol [server]
+  (if (:ssl server) "smtps" "smtp"))
+
+(defn get-transport [^Session session ^String protocol]
+  (.getTransport session protocol))
+
+(defn connect! [^Transport transport server]
+  (let [{:keys [host port user pass]} server]
+    (assert (or (and (nil? user) (nil? pass)) (and user pass)))
+    (.connect transport host port user pass)))
+
+(defn transport-send
+  ([^Transport transport ^Session session msg]
+   (transport-send transport (make-jmessage msg session)))
+  ([^Transport transport ^javax.mail.Message jmsg]
+   (.sendMessage transport jmsg (.getAllRecipients jmsg))
+   {:code 0 :error :SUCCESS :message "messages sent"}))
+
 (defn ^:dynamic smtp-send* [^Session session ^String proto
-                            {:keys [host port user pass]} msgs]
-  (assert (or (and (nil? user) (nil? pass)) (and user pass)))
-  (with-open [transport (.getTransport session proto)]
-    (.connect transport host port user pass)
+                            {:keys [user pass] :as args} msgs]
+  (with-open [^Transport transport (get-transport session proto)]
+    (connect! transport args)
     (let [jmsgs (map #(make-jmessage % session) msgs)]
       (doseq [^javax.mail.Message jmsg jmsgs]
-        (.sendMessage transport jmsg (.getAllRecipients jmsg)))
+        (transport-send transport jmsg))
       {:code 0 :error :SUCCESS :message "messages sent"})))
 
 (defn smtp-send
@@ -45,14 +67,13 @@
          (catch Exception e
            {:code 99 :error (class e) :message (.getMessage e)}))))
   ([args & msgs]
-     (let [{:keys [host port user pass sender ssl debug]
+     (let [{:keys [host port ssl]
             :or {host "localhost"}} args
             port (if (nil? port)
                    (if ssl 465 25)
                    port)
-            proto (if ssl "smtps" "smtp")
+            proto (get-protocol args)
             args (merge args {:port port
                               :proto proto})
-            session (doto (Session/getInstance (make-props sender args))
-                      (.setDebug (if debug true false)))]
+            session (get-session args)]
        (smtp-send* session proto args msgs))))