loki disable if non valid url

lokiwriter.go

@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"net/http"
+	"net/url"
 	"sync"
 	"time"
 )
@@ -13,6 +14,7 @@ type LokiWriter struct {
 	url        string
 	labels     map[string]string
 	httpClient *http.Client
+	disabled   bool
 
 	// Circuit breaker fields
 	mu              sync.RWMutex
@@ -38,15 +40,29 @@ const (
 	warningInterval    = 1 * time.Minute // Minimum time between warning messages
 )
 
-func NewLokiWriter(url string, labels map[string]string) *LokiWriter {
+func NewLokiWriter(rawURL string, labels map[string]string) *LokiWriter {
+	disabled := false
+	if rawURL == "" {
+		disabled = true
+	} else {
+		u, err := url.ParseRequestURI(rawURL)
+		if err != nil || (u.Scheme != "http" && u.Scheme != "https") || u.Host == "" {
+			disabled = true
+		}
+	}
 	return &LokiWriter{
-		url:        url,
+		url:        rawURL,
 		labels:     labels,
 		httpClient: &http.Client{},
+		disabled:   disabled,
 	}
 }
 
 func (w *LokiWriter) Write(p []byte) (n int, err error) {
+	if w.disabled {
+		return len(p), nil
+	}
+
 	// Check circuit breaker status
 	w.mu.RLock()
 	if w.circuitOpen {