From 52bac8aef5e976e7b8d982f6ddde4ee0e436fe6c Mon Sep 17 00:00:00 2001
From: rcmerci <rcmerci@gmail.com>
Date: Sat, 10 Jan 2026 00:17:35 +0800
Subject: [PATCH] enhance(worker-sync): add ws reconnect backoff

---
 src/main/frontend/worker/worker_sync.cljs | 58 +++++++++++++++++++++--
 1 file changed, 53 insertions(+), 5 deletions(-)

diff --git a/src/main/frontend/worker/worker_sync.cljs b/src/main/frontend/worker/worker_sync.cljs
index 9a2f734f02..e8d9e28c77 100644
--- a/src/main/frontend/worker/worker_sync.cljs
+++ b/src/main/frontend/worker/worker_sync.cljs
@@ -47,6 +47,9 @@
 
 (def ^:private max-asset-size (* 100 1024 1024))
 (def ^:private upload-kvs-batch-size 2000)
+(def ^:private reconnect-base-delay-ms 1000)
+(def ^:private reconnect-max-delay-ms 30000)
+(def ^:private reconnect-jitter-ms 250)
 
 (defn- format-ws-url [base graph-id]
   (cond
@@ -82,6 +85,22 @@
 (defn- ws-open? [ws]
   (= 1 (ready-state ws)))
 
+(defn- reconnect-delay-ms [attempt]
+  (let [exp (js/Math.pow 2 attempt)
+        delay (min reconnect-max-delay-ms (* reconnect-base-delay-ms exp))
+        jitter (rand-int reconnect-jitter-ms)]
+    (+ delay jitter)))
+
+(defn- clear-reconnect-timer! [reconnect]
+  (when-let [timer (:timer @reconnect)]
+    (js/clearTimeout timer)
+    (swap! reconnect assoc :timer nil)))
+
+(defn- reset-reconnect! [client]
+  (when-let [reconnect (:reconnect client)]
+    (clear-reconnect-timer! reconnect)
+    (swap! reconnect assoc :attempt 0)))
+
 (defn- send! [ws message]
   (when (ws-open? ws)
     (.send ws (js/JSON.stringify (clj->js message)))))
@@ -206,7 +225,8 @@
       (let [client {:repo repo
                     :send-queue (atom (p/resolved nil))
                     :asset-queue (atom (p/resolved nil))
-                    :inflight (atom [])}]
+                    :inflight (atom [])
+                    :reconnect (atom {:attempt 0 :timer nil})}]
         (swap! worker-state/*worker-sync-clients assoc repo client)
         client)))
 
@@ -473,18 +493,45 @@
                              :t_before (or (client-op/get-local-tx repo) 0)
                              :txs txs}))))))))))
 
-(defn- attach-ws-handlers! [repo client ws]
+(declare connect!)
+
+(defn- schedule-reconnect! [repo client url reason]
+  (when (enabled?)
+    (when-let [reconnect (:reconnect client)]
+      (let [{:keys [attempt timer]} @reconnect]
+        (when (nil? timer)
+          (let [delay (reconnect-delay-ms attempt)
+                timeout-id (js/setTimeout
+                            (fn []
+                              (swap! reconnect assoc :timer nil)
+                              (when (enabled?)
+                                (when-let [current (get @worker-state/*worker-sync-clients repo)]
+                                  (when (= (:graph-id current) (:graph-id client))
+                                    (let [updated (connect! repo current url)]
+                                      (swap! worker-state/*worker-sync-clients assoc repo updated))))))
+                            delay)]
+            (swap! reconnect assoc :timer timeout-id :attempt (inc attempt))
+            (log/info :worker-sync/ws-reconnect-scheduled
+                      {:repo repo :delay delay :attempt attempt :reason reason})))))))
+
+(defn- attach-ws-handlers! [repo client ws url]
   (set! (.-onmessage ws)
         (fn [event]
           (handle-message! repo client (.-data event))))
+  (set! (.-onerror ws)
+        (fn [event]
+          (log/error :worker-sync/ws-error {:repo repo :error event})))
   (set! (.-onclose ws)
         (fn [_]
-          (log/info :worker-sync/ws-closed {:repo repo}))))
+          (log/info :worker-sync/ws-closed {:repo repo})
+          (schedule-reconnect! repo client url :close))))
 
-(defn- start-pull-loop! [client ws]
+(defn- start-pull-loop! [client _ws]
   client)
 
 (defn- stop-client! [client]
+  (when-let [reconnect (:reconnect client)]
+    (clear-reconnect-timer! reconnect))
   (when-let [ws (:ws client)]
     (try
       (.close ws)
@@ -494,9 +541,10 @@
 (defn- connect! [repo client url]
   (let [ws (js/WebSocket. (append-token url (auth-token)))
         updated (assoc client :ws ws)]
-    (attach-ws-handlers! repo updated ws)
+    (attach-ws-handlers! repo updated ws url)
     (set! (.-onopen ws)
           (fn [_]
+            (reset-reconnect! updated)
             (send! ws {:type "hello" :client repo})
             (enqueue-asset-sync! repo updated)
             (enqueue-asset-initial-download! repo updated)))