Use a heartbeat to allow the client to reconnect after network failures.

1 files changed, 27 insertions, 0 deletions

diff --git a/ui/lib/watchdog.js b/ui/lib/watchdog.js
new file mode 100644
index 0000000..c95fd4d
--- /dev/null
+++ b/ui/lib/watchdog.js
@@ -0,0 +1,27 @@
+export class Watchdog {
+  constructor(onExpired) {
+    this.timeout = null;
+    this.onExpired = onExpired;
+  }
+
+  reset(delay) {
+    if (this.timeout !== null) {
+      clearTimeout(this.timeout);
+    }
+    this.timeout = setTimeout(this.expire.bind(this), delay);
+  }
+
+  stop() {
+    if (this.timeout !== null) {
+      clearTimeout(this.timeout);
+      this.timeout = null;
+    }
+  }
+
+  expire() {
+    if (this.timeout !== null) {
+      this.timeout = null;
+    }
+    this.onExpired();
+  }
+}