Address code review feedback: fix typo and prevent overlapping executions

- Fix spelling: 'retrived' -> 'retrieved' in proxysessionmetrics.js
- Add flag to prevent overlapping health check executions
- Change back to sequential server processing to avoid overwhelming Sense servers
- Add warning log when skipping intervals due to long-running health checks

Co-authored-by: mountaindude <1029262+mountaindude@users.noreply.github.com>

src/lib/healthmetrics.js

@@ -156,18 +156,33 @@ export async function getHealthStatsFromSense(serverName, host, tags, headers, r
  *
  * This function creates an interval that runs every pollingInterval milliseconds (as defined in config)
  * and calls getHealthStatsFromSense for each server in the serverList global variable.
+ * Uses a flag to prevent overlapping executions if health checks take longer than the polling interval.
  *
  * @returns {void}
  */
 export function setupHealthMetricsTimer() {
+    let isCollecting = false;
+
     // Configure timer for getting healthcheck data
     setInterval(async () => {
+        // Prevent overlapping executions
+        if (isCollecting) {
+            globals.logger.warn(
+                'HEALTH: Previous health check collection still in progress, skipping this interval'
+            );
+            return;
+        }
+
+        isCollecting = true;
+        try {
             globals.logger.verbose('HEALTH: Event started: Statistics collection');
 
-        // Process all servers concurrently with error handling
-        const healthCheckPromises = globals.serverList.map(async (server) => {
+            // Process servers sequentially to avoid overwhelming the Sense servers
+            for (const server of globals.serverList) {
                 try {
-                globals.logger.verbose(`HEALTH: Getting stats for server: ${server.serverName}`);
+                    globals.logger.verbose(
+                        `HEALTH: Getting stats for server: ${server.serverName}`
+                    );
                     globals.logger.debug(`HEALTH: Server details: ${JSON.stringify(server)}`);
 
                     // Get per-server tags
@@ -182,9 +197,9 @@ export function setupHealthMetricsTimer() {
                         `HEALTH: Unexpected error processing health stats for server '${server.serverName}': ${globals.getErrorMessage(err)}`
                     );
                 }
-        });
-
-        // Wait for all health checks to complete
-        await Promise.allSettled(healthCheckPromises);
+            }
+        } finally {
+            isCollecting = false;
+        }
     }, globals.config.get('Butler-SOS.serversToMonitor.pollingInterval'));
 }

src/lib/proxysessionmetrics.js

@@ -222,7 +222,7 @@ export async function getProxySessionStatsFromSense(
     influxTags,
     retryCount = 0
 ) {
-    // Current user sessions are retrived using this API:
+    // Current user sessions are retrieved using this API:
     // https://help.qlik.com/en-US/sense-developer/February2021/Subsystems/ProxyServiceAPI/Content/Sense_ProxyServiceAPI/ProxyServiceAPI-Proxy-API.htm
 
     // Get certificate configuration options