v0.7.35 - Implement event-driven monitoring system with dual triggers for events and subscriptions

src/api.c

@@ -377,8 +377,8 @@ cJSON* query_subscription_details(void) {
     return subscriptions_data;
 }
 
-// Generate and broadcast monitoring event
-int generate_monitoring_event(void) {
+// Generate event-driven monitoring events (triggered by event storage)
+int generate_event_driven_monitoring(void) {
     // Generate event_kinds monitoring event
     if (generate_monitoring_event_for_type("event_kinds", query_event_kind_distribution) != 0) {
         DEBUG_ERROR("Failed to generate event_kinds monitoring event");
@@ -403,22 +403,45 @@ int generate_monitoring_event(void) {
         return -1;
     }
 
+    // Generate CPU metrics monitoring event (also triggered by event storage)
+    if (generate_monitoring_event_for_type("cpu_metrics", query_cpu_metrics) != 0) {
+        DEBUG_ERROR("Failed to generate cpu_metrics monitoring event");
+        return -1;
+    }
+
+    DEBUG_INFO("Generated and broadcast event-driven monitoring events");
+    return 0;
+}
+
+// Generate subscription-driven monitoring events (triggered by subscription changes)
+int generate_subscription_driven_monitoring(void) {
+    // Generate active_subscriptions monitoring event (subscription changes affect this)
+    if (generate_monitoring_event_for_type("active_subscriptions", query_active_subscriptions) != 0) {
+        DEBUG_ERROR("Failed to generate active_subscriptions monitoring event");
+        return -1;
+    }
+
     // Generate subscription_details monitoring event (admin-only)
     if (generate_monitoring_event_for_type("subscription_details", query_subscription_details) != 0) {
         DEBUG_ERROR("Failed to generate subscription_details monitoring event");
         return -1;
     }
 
-    // Generate CPU metrics monitoring event
+    // Generate CPU metrics monitoring event (also triggered by subscription changes)
     if (generate_monitoring_event_for_type("cpu_metrics", query_cpu_metrics) != 0) {
         DEBUG_ERROR("Failed to generate cpu_metrics monitoring event");
         return -1;
     }
 
-    DEBUG_INFO("Generated and broadcast all monitoring events");
+    DEBUG_INFO("Generated and broadcast subscription-driven monitoring events");
     return 0;
 }
 
+// Generate and broadcast monitoring event (legacy function - now calls event-driven version)
+int generate_monitoring_event(void) {
+    return generate_event_driven_monitoring();
+}
+
 // Helper function to generate monitoring event for a specific type
 int generate_monitoring_event_for_type(const char* d_tag_value, cJSON* (*query_func)(void)) {
     // Query the monitoring data
@@ -511,20 +534,42 @@ void monitoring_on_event_stored(void) {
     static time_t last_monitoring_time = 0;
     time_t current_time = time(NULL);
     int throttle_seconds = get_monitoring_throttle_seconds();
-    
+
     if (current_time - last_monitoring_time < throttle_seconds) {
         return;
     }
-    
+
     // Check if anyone is subscribed to monitoring events (kind 24567)
     // This is the ONLY activation check needed - if someone subscribes, they want monitoring
     if (!has_subscriptions_for_kind(24567)) {
         return; // No subscribers = no expensive operations
     }
-    
-    // Generate monitoring events only when someone is listening
+
+    // Generate event-driven monitoring events only when someone is listening
     last_monitoring_time = current_time;
-    generate_monitoring_event();
+    generate_event_driven_monitoring();
+}
+
+// Monitoring hook called when subscriptions change (create/close)
+void monitoring_on_subscription_change(void) {
+    // Check throttling first (cheapest check)
+    static time_t last_monitoring_time = 0;
+    time_t current_time = time(NULL);
+    int throttle_seconds = get_monitoring_throttle_seconds();
+
+    if (current_time - last_monitoring_time < throttle_seconds) {
+        return;
+    }
+
+    // Check if anyone is subscribed to monitoring events (kind 24567)
+    // This is the ONLY activation check needed - if someone subscribes, they want monitoring
+    if (!has_subscriptions_for_kind(24567)) {
+        return; // No subscribers = no expensive operations
+    }
+
+    // Generate subscription-driven monitoring events only when someone is listening
+    last_monitoring_time = current_time;
+    generate_subscription_driven_monitoring();
 }
 
 // Forward declaration for known_configs (defined in config.c)