FEATURE (logs): Add Victora Logs

backend/.env.development.example

@@ -6,6 +6,8 @@ DEV_DB_PASSWORD=Q1234567
 ENV_MODE=development
 # logging
 SHOW_DB_INSTALLATION_VERIFICATION_LOGS=true
+VICTORIA_LOGS_URL=http://localhost:9428
+VICTORIA_LOGS_PASSWORD=devpassword
 # tests
 TEST_LOCALHOST=localhost
 IS_SKIP_EXTERNAL_RESOURCES_TESTS=false

backend/.gitignore

@@ -18,4 +18,5 @@ pgdata-for-restore/
 temp/
 cmd.exe
 temp/
-valkey-data/
+valkey-data/
+victoria-logs-data/

backend/cmd/main.go

@@ -185,6 +185,9 @@ func startServerWithGracefulShutdown(log *slog.Logger, app *gin.Engine) {
 	<-quit
 	log.Info("Shutdown signal received")
 
+	// Gracefully shutdown VictoriaLogs writer
+	logger.ShutdownVictoriaLogs(5 * time.Second)
+
 	// The context is used to inform the server it has 10 seconds to finish
 	// the request it is currently handling
 	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)

backend/docker-compose.yml.example

@@ -34,6 +34,20 @@ services:
       retries: 5
       start_period: 20s
 
+  # VictoriaLogs for external logging
+  victoria-logs:
+    image: victoriametrics/victoria-logs:latest
+    container_name: victoria-logs
+    ports:
+      - "9428:9428"
+    command:
+      - -storageDataPath=/victoria-logs-data
+      - -retentionPeriod=7d
+      - -httpAuth.password=devpassword
+    volumes:
+      - ./victoria-logs-data:/victoria-logs-data
+    restart: unless-stopped
+
   # Test MinIO container
   test-minio:
     image: minio/minio:latest

backend/internal/util/logger/logger.go

@@ -1,48 +1,131 @@
 package logger
 
 import (
+	"fmt"
 	"log/slog"
 	"os"
+	"path/filepath"
 	"sync"
 	"time"
+
+	"github.com/joho/godotenv"
 )
 
 var (
-	loggerInstance *slog.Logger
-	once           sync.Once
+	loggerInstance     *slog.Logger
+	victoriaLogsWriter *VictoriaLogsWriter
+	once               sync.Once
+	shutdownOnce       sync.Once
+	envLoadOnce        sync.Once
 )
 
 // GetLogger returns a singleton slog.Logger that logs to the console
 func GetLogger() *slog.Logger {
 	once.Do(func() {
-		handler := slog.NewTextHandler(os.Stdout, &slog.HandlerOptions{
+		// Create stdout handler
+		stdoutHandler := slog.NewTextHandler(os.Stdout, &slog.HandlerOptions{
 			Level: slog.LevelInfo,
 			ReplaceAttr: func(groups []string, a slog.Attr) slog.Attr {
 				if a.Key == slog.TimeKey {
 					a.Value = slog.StringValue(time.Now().Format("2006/01/02 15:04:05"))
 				}
-
-				if a.Key == slog.MessageKey {
-					// Format the message to match the desired output format
-					return slog.Attr{
-						Key:   slog.MessageKey,
-						Value: slog.StringValue(a.Value.String()),
-					}
-				}
-
-				// Remove level and other attributes to get clean output
 				if a.Key == slog.LevelKey {
 					return slog.Attr{}
 				}
-
 				return a
 			},
 		})
 
-		loggerInstance = slog.New(handler)
+		// Try to initialize VictoriaLogs writer if configured
+		// Note: This will be called before config is fully loaded in some cases,
+		// so we need to handle that gracefully
+		victoriaLogsWriter = tryInitVictoriaLogs()
+
+		// Create multi-handler
+		multiHandler := NewMultiHandler(stdoutHandler, victoriaLogsWriter)
+		loggerInstance = slog.New(multiHandler)
 
 		loggerInstance.Info("Text structured logger initialized")
+		if victoriaLogsWriter != nil {
+			loggerInstance.Info("VictoriaLogs enabled")
+		} else {
+			loggerInstance.Info("VictoriaLogs disabled")
+		}
 	})
 
 	return loggerInstance
 }
+
+// ShutdownVictoriaLogs gracefully shuts down the VictoriaLogs writer
+func ShutdownVictoriaLogs(timeout time.Duration) {
+	shutdownOnce.Do(func() {
+		if victoriaLogsWriter != nil {
+			victoriaLogsWriter.Shutdown(timeout)
+		}
+	})
+}
+
+func tryInitVictoriaLogs() *VictoriaLogsWriter {
+	// Ensure .env is loaded before reading environment variables
+	ensureEnvLoaded()
+
+	// Try to get config - this may fail early in startup
+	url := getVictoriaLogsURL()
+	password := getVictoriaLogsPassword()
+
+	if url == "" {
+		fmt.Println("VictoriaLogs URL is not set")
+		return nil
+	}
+
+	return NewVictoriaLogsWriter(url, password)
+}
+
+func ensureEnvLoaded() {
+	envLoadOnce.Do(func() {
+		// Get current working directory
+		cwd, err := os.Getwd()
+		if err != nil {
+			fmt.Printf("Warning: could not get current working directory: %v\n", err)
+			cwd = "."
+		}
+
+		// Find backend root by looking for go.mod
+		backendRoot := cwd
+		for {
+			if _, err := os.Stat(filepath.Join(backendRoot, "go.mod")); err == nil {
+				break
+			}
+
+			parent := filepath.Dir(backendRoot)
+			if parent == backendRoot {
+				break
+			}
+
+			backendRoot = parent
+		}
+
+		// Try to load .env from various locations
+		envPaths := []string{
+			filepath.Join(cwd, ".env"),
+			filepath.Join(backendRoot, ".env"),
+		}
+
+		for _, path := range envPaths {
+			if err := godotenv.Load(path); err == nil {
+				fmt.Printf("Logger: loaded .env from %s\n", path)
+				return
+			}
+		}
+
+		fmt.Println("Logger: .env file not found, using existing environment variables")
+	})
+}
+
+func getVictoriaLogsURL() string {
+	return os.Getenv("VICTORIA_LOGS_URL")
+}
+
+func getVictoriaLogsPassword() string {
+	return os.Getenv("VICTORIA_LOGS_PASSWORD")
+}

backend/internal/util/logger/multi_handler.go

@@ -0,0 +1,59 @@
+package logger
+
+import (
+	"context"
+	"log/slog"
+)
+
+type MultiHandler struct {
+	stdoutHandler      slog.Handler
+	victoriaLogsWriter *VictoriaLogsWriter
+}
+
+func NewMultiHandler(
+	stdoutHandler slog.Handler,
+	victoriaLogsWriter *VictoriaLogsWriter,
+) *MultiHandler {
+	return &MultiHandler{
+		stdoutHandler:      stdoutHandler,
+		victoriaLogsWriter: victoriaLogsWriter,
+	}
+}
+
+func (h *MultiHandler) Enabled(ctx context.Context, level slog.Level) bool {
+	return h.stdoutHandler.Enabled(ctx, level)
+}
+
+func (h *MultiHandler) Handle(ctx context.Context, record slog.Record) error {
+	// Send to stdout handler
+	if err := h.stdoutHandler.Handle(ctx, record); err != nil {
+		return err
+	}
+
+	// Send to VictoriaLogs if configured
+	if h.victoriaLogsWriter != nil {
+		attrs := make(map[string]interface{})
+		record.Attrs(func(a slog.Attr) bool {
+			attrs[a.Key] = a.Value.Any()
+			return true
+		})
+
+		h.victoriaLogsWriter.Write(record.Level.String(), record.Message, attrs)
+	}
+
+	return nil
+}
+
+func (h *MultiHandler) WithAttrs(attrs []slog.Attr) slog.Handler {
+	return &MultiHandler{
+		stdoutHandler:      h.stdoutHandler.WithAttrs(attrs),
+		victoriaLogsWriter: h.victoriaLogsWriter,
+	}
+}
+
+func (h *MultiHandler) WithGroup(name string) slog.Handler {
+	return &MultiHandler{
+		stdoutHandler:      h.stdoutHandler.WithGroup(name),
+		victoriaLogsWriter: h.victoriaLogsWriter,
+	}
+}

backend/internal/util/logger/victorialogs_writer.go

@@ -0,0 +1,201 @@
+package logger
+
+import (
+	"bytes"
+	"context"
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
+	"io"
+	"log/slog"
+	"net/http"
+	"os"
+	"sync"
+	"time"
+)
+
+type logEntry struct {
+	Time    string         `json:"_time"`
+	Message string         `json:"_msg"`
+	Level   string         `json:"level"`
+	Attrs   map[string]any `json:",inline"`
+}
+
+type VictoriaLogsWriter struct {
+	url        string
+	password   string
+	httpClient *http.Client
+	logChannel chan logEntry
+	wg         sync.WaitGroup
+	once       sync.Once
+	ctx        context.Context
+	cancel     context.CancelFunc
+	logger     *slog.Logger
+}
+
+func NewVictoriaLogsWriter(url, password string) *VictoriaLogsWriter {
+	ctx, cancel := context.WithCancel(context.Background())
+
+	writer := &VictoriaLogsWriter{
+		url:      url,
+		password: password,
+		httpClient: &http.Client{
+			Timeout: 10 * time.Second,
+		},
+		logChannel: make(chan logEntry, 1000),
+		ctx:        ctx,
+		cancel:     cancel,
+		logger:     slog.New(slog.NewTextHandler(os.Stdout, nil)),
+	}
+
+	// Start 3 worker goroutines
+	for range 3 {
+		writer.wg.Add(1)
+		go writer.worker()
+	}
+
+	return writer
+}
+
+func (w *VictoriaLogsWriter) Write(level, message string, attrs map[string]interface{}) {
+	entry := logEntry{
+		Time:    time.Now().UTC().Format(time.RFC3339Nano),
+		Message: message,
+		Level:   level,
+		Attrs:   attrs,
+	}
+
+	select {
+	case w.logChannel <- entry:
+		// Successfully queued
+	default:
+		// Channel is full, drop log with warning
+		w.logger.Warn("VictoriaLogs channel buffer full, dropping log entry")
+	}
+}
+
+func (w *VictoriaLogsWriter) worker() {
+	defer w.wg.Done()
+
+	batch := make([]logEntry, 0, 100)
+	ticker := time.NewTicker(1 * time.Second)
+	defer ticker.Stop()
+
+	for {
+		select {
+		case <-w.ctx.Done():
+			w.flushBatch(batch)
+			return
+
+		case entry, ok := <-w.logChannel:
+			if !ok {
+				w.flushBatch(batch)
+				return
+			}
+
+			batch = append(batch, entry)
+
+			// Send batch if it reaches 100 entries
+			if len(batch) >= 100 {
+				w.sendBatch(batch)
+				batch = make([]logEntry, 0, 100)
+			}
+
+		case <-ticker.C:
+			if len(batch) > 0 {
+				w.sendBatch(batch)
+				batch = make([]logEntry, 0, 100)
+			}
+		}
+	}
+}
+
+func (w *VictoriaLogsWriter) sendBatch(entries []logEntry) {
+	backoffs := []time.Duration{0, 5 * time.Second, 30 * time.Second, 1 * time.Minute}
+
+	for attempt := range 4 {
+		if backoffs[attempt] > 0 {
+			time.Sleep(backoffs[attempt])
+		}
+
+		if err := w.sendHTTP(entries); err == nil {
+			return
+		} else if attempt == 3 {
+			w.logger.Error("VictoriaLogs failed to send logs after 4 attempts",
+				"error", err,
+				"entries_count", len(entries))
+		}
+	}
+}
+
+func (w *VictoriaLogsWriter) sendHTTP(entries []logEntry) error {
+	// Build JSON Lines payload
+	var buf bytes.Buffer
+	encoder := json.NewEncoder(&buf)
+
+	for _, entry := range entries {
+		if err := encoder.Encode(entry); err != nil {
+			return fmt.Errorf("failed to encode log entry: %w", err)
+		}
+	}
+
+	// Build request
+	url := fmt.Sprintf("%s/insert/jsonline?_stream_fields=level&_msg_field=_msg", w.url)
+	req, err := http.NewRequestWithContext(w.ctx, "POST", url, &buf)
+	if err != nil {
+		return fmt.Errorf("failed to create request: %w", err)
+	}
+
+	// Set headers
+	req.Header.Set("Content-Type", "application/x-ndjson")
+
+	// Set Basic Auth (password as username, empty password)
+	if w.password != "" {
+		auth := base64.StdEncoding.EncodeToString([]byte(w.password + ":"))
+		req.Header.Set("Authorization", "Basic "+auth)
+	}
+
+	// Send request
+	resp, err := w.httpClient.Do(req)
+	if err != nil {
+		return fmt.Errorf("failed to send request: %w", err)
+	}
+	defer func() {
+		_ = resp.Body.Close()
+	}()
+
+	// Check response
+	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		body, _ := io.ReadAll(resp.Body)
+		return fmt.Errorf("VictoriaLogs returned status %d: %s", resp.StatusCode, string(body))
+	}
+
+	return nil
+}
+
+func (w *VictoriaLogsWriter) flushBatch(batch []logEntry) {
+	if len(batch) > 0 {
+		w.sendBatch(batch)
+	}
+}
+
+func (w *VictoriaLogsWriter) Shutdown(timeout time.Duration) {
+	w.once.Do(func() {
+		// Stop accepting new logs
+		w.cancel()
+
+		// Wait for workers to finish with timeout
+		done := make(chan struct{})
+		go func() {
+			w.wg.Wait()
+			close(done)
+		}()
+
+		select {
+		case <-done:
+			w.logger.Info("VictoriaLogs writer shutdown gracefully")
+		case <-time.After(timeout):
+			w.logger.Warn("VictoriaLogs writer shutdown timeout, some logs may be lost")
+		}
+	})
+}