Code: add tracking requests by source IP

main.go

@@ -91,14 +91,15 @@ type LoadBalancer struct {
     ProxyCacheMutex sync.RWMutex
 
     // Prometheus metrics
-    latencyGauge      *prometheus.GaugeVec
-    chainheadGauge    *prometheus.GaugeVec
-    blocksBehindGauge *prometheus.GaugeVec
-    loadGauge         *prometheus.GaugeVec
-    errorCounter      *prometheus.CounterVec
-    bestEndpointGauge *prometheus.GaugeVec
-    requestCounter    *prometheus.CounterVec
-    requestDuration   *prometheus.HistogramVec
+    latencyGauge        *prometheus.GaugeVec
+    chainheadGauge      *prometheus.GaugeVec
+    blocksBehindGauge   *prometheus.GaugeVec
+    loadGauge           *prometheus.GaugeVec
+    errorCounter        *prometheus.CounterVec
+    bestEndpointGauge   *prometheus.GaugeVec
+    requestCounter      *prometheus.CounterVec
+    requestDuration     *prometheus.HistogramVec
+    requestByIPCounter  *prometheus.CounterVec // New metric
 
     // Custom Prometheus registry
     promRegistry *prometheus.Registry
@@ -109,6 +110,7 @@ func logMessage(globalLevel string, level string, format string, args ...interfa
         "ERROR": 0,
         "INFO":  1,
         "DEBUG": 2,
+        "TRACE": 3,
     }
 
     if levels[level] <= levels[globalLevel] {
@@ -237,6 +239,15 @@ func (lb *LoadBalancer) initMetrics() {
         []string{"network"},
     )
 
+    // New metric for requests by client IP
+    lb.requestByIPCounter = prometheus.NewCounterVec(
+        prometheus.CounterOpts{
+            Name: "loadbalancer_requests_by_ip_total",
+            Help: "Total number of requests by client IP",
+        },
+        []string{"network", "client_ip"},
+    )
+
     // Register only the custom metrics with the custom registry
     lb.promRegistry.MustRegister(lb.latencyGauge)
     lb.promRegistry.MustRegister(lb.chainheadGauge)
@@ -246,6 +257,7 @@ func (lb *LoadBalancer) initMetrics() {
     lb.promRegistry.MustRegister(lb.bestEndpointGauge)
     lb.promRegistry.MustRegister(lb.requestCounter)
     lb.promRegistry.MustRegister(lb.requestDuration)
+    lb.promRegistry.MustRegister(lb.requestByIPCounter) // Register new metric
 }
 
 func (lb *LoadBalancer) logRateLimited(level string, key string, format string, args ...interface{}) {
@@ -573,6 +585,27 @@ func (lb *LoadBalancer) getValidEndpoints(nodes []*NodeStatus, endpointChainhead
     return validEndpoints
 }
 
+// getClientIP extracts the client IP address from the request.
+func getClientIP(r *http.Request) string {
+    // Try to get the IP from the X-Forwarded-For header
+    xForwardedFor := r.Header.Get("X-Forwarded-For")
+    if xForwardedFor != "" {
+        // X-Forwarded-For can be a comma-separated list of IPs
+        ips := strings.Split(xForwardedFor, ",")
+        // Return the first IP
+        ip := strings.TrimSpace(ips[0])
+        if ip != "" {
+            return ip
+        }
+    }
+    // Fallback to RemoteAddr
+    ip, _, err := net.SplitHostPort(r.RemoteAddr)
+    if err != nil {
+        return r.RemoteAddr
+    }
+    return ip
+}
+
 func (lb *LoadBalancer) ServeHTTP(w http.ResponseWriter, r *http.Request) {
     startTime := time.Now()
     pathSegments := strings.Split(strings.Trim(r.URL.Path, "/"), "/")
@@ -604,9 +637,18 @@ func (lb *LoadBalancer) ServeHTTP(w http.ResponseWriter, r *http.Request) {
         return
     }
 
+    // Extract the client IP
+    clientIP := getClientIP(r)
+
+    // Log the client IP at TRACE level, obeying the rate limit
+    lb.logRateLimited("TRACE", "client_ip_"+clientIP+"_"+networkName, "Client IP %s made a request to network %s", clientIP, networkName)
+
     // Increment request counter
     lb.requestCounter.WithLabelValues(networkName).Inc()
 
+    // Increment request counter by client IP
+    lb.requestByIPCounter.WithLabelValues(networkName, clientIP).Inc()
+
     // Serve the request using the proxy
     proxy.ServeHTTP(w, r)