From de6fa83e96923dad99a56e97fdab8c5df63fdb01 Mon Sep 17 00:00:00 2001
From: Andrey Antukh <niwi@niwi.nz>
Date: Thu, 23 Jan 2020 15:47:01 +0100
Subject: [PATCH] :tada: Add high level `schedule!` function to vertx.timers.

---
 backend/vendor/vertx/src/vertx/timers.clj | 41 +++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/backend/vendor/vertx/src/vertx/timers.clj b/backend/vendor/vertx/src/vertx/timers.clj
index 84213c0f3..ed8098822 100644
--- a/backend/vendor/vertx/src/vertx/timers.clj
+++ b/backend/vendor/vertx/src/vertx/timers.clj
@@ -14,6 +14,8 @@
    io.vertx.core.Vertx
    io.vertx.core.Handler))
 
+;; --- Low Level API
+
 (defn schedule-once!
   [vsm ms f]
   (let [^Vertx system (vu/resolve-system vsm)
@@ -33,3 +35,42 @@
       java.lang.AutoCloseable
       (close [_]
         (.cancelTimer system timer-id)))))
+
+;; --- High Level API
+
+(s/def ::once boolean?)
+(s/def ::repeat boolean?)
+(s/def ::delay integer?)
+(s/def ::fn (s/or :fn fn? :var var?))
+
+(s/def ::schedule-opts
+  (s/keys :req [::fn ::delay] :opt [::once ::repeat]))
+
+(defn schedule!
+  "High level schedule function."
+  [vsm {:keys [::once ::repeat ::delay] :as opts}]
+  (s/assert ::schedule-opts opts)
+
+  (when (and (not once) (not repeat))
+    (throw (IllegalArgumentException. "you should specify `once` or `repeat` params")))
+
+  (let [system (vu/resolve-system vsm)
+        state  (atom nil)
+        taskfn (fn wrapped-task []
+                 (-> (p/do! ((::fn opts) opts))
+                     (p/catch' (constantly nil)) ; explicitly ignore all errors
+                     (p/then'  (fn [_]            ; the user needs to catch errors
+                                 (when repeat
+                                   (let [tid (schedule-once! vsm delay wrapped-task)]
+                                     (reset! state tid)
+                                     nil))))))
+        tid  (schedule-once! vsm delay taskfn)]
+    (reset! state tid)
+    (reify
+      java.lang.AutoCloseable
+      (close [this]
+        (locking this
+          (when-let [timer-id (deref state)]
+            (.cancelTimer system timer-id)
+            (reset! state nil)))))))
+