Ham HF band toggle preset and prevent some multiple-SSE shenanigans when searching and typing letters quickly

webassets/js/spots.js

@@ -1,5 +1,6 @@
 // SSE event source
 let evtSource;
+let restartSSEOnErrorTimeoutId;
 // Table row count, to alternate shading
 let rowCount = 0;
 
@@ -30,6 +31,9 @@ function loadSpots() {
 // Start an SSE connection (closing an existing one if it exists). This will then be used to add to the table on the
 // fly.
 function startSSEConnection() {
+    if (evtSource != null) {
+        evtSource.close();
+    }
     evtSource = new EventSource('/api/v1/spots/stream' + buildQueryString());
 
     evtSource.onmessage = function(event) {
@@ -66,8 +70,11 @@ function startSSEConnection() {
     };
 
     evtSource.onerror = function(err) {
-        evtSource.close();
-        setTimeout(startSSEConnection, 1000);
+        if (evtSource != null) {
+            evtSource.close();
+        }
+        clearTimeout(restartSSEOnErrorTimeoutId)
+        restartSSEOnErrorTimeoutId = setTimeout(startSSEConnection, 1000);
     };
 }