From 2cd8479908052d73785e78df9e5b8b9f9f09b031 Mon Sep 17 00:00:00 2001
From: "maksim.konovalov" <maksim.konovalov@vk.team>
Date: Thu, 23 Jan 2025 12:39:42 +0300
Subject: [PATCH] Add slog logger provider

---
 CHANGELOG.md      |  3 +++
 providers.go      | 36 ++++++++++++++++++++++++++++++++++++
 providers_test.go | 43 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 82 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 09e1854..22fb03d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,8 @@
 ## Unreleased
 
+FEATURES:
+- Slog provider is available now. Use NewSlogLogger for slog log provider creation.
+
 BUG FIXES:
 - Fixed go.mod and go.sum files with go mod tidy.
 
diff --git a/providers.go b/providers.go
index abaa1c4..59b7a42 100644
--- a/providers.go
+++ b/providers.go
@@ -2,7 +2,9 @@ package vshard_router //nolint:revive
 
 import (
 	"context"
+	"fmt"
 	"log"
+	"log/slog"
 	"time"
 )
 
@@ -12,6 +14,8 @@ var (
 
 	// Ensure StdoutLoggerf implements LogfProvider
 	_ LogfProvider = StdoutLoggerf{}
+	// Ensure SlogLoggerf implements LogfProvider
+	_ LogfProvider = &SlogLoggerf{}
 )
 
 // LogfProvider an interface to inject a custom logger.
@@ -83,6 +87,38 @@ func (s StdoutLoggerf) Errorf(_ context.Context, format string, v ...any) {
 	s.printLevel(StdoutLogError, "[ERROR] ", format, v...)
 }
 
+// NewSlogLogger wraps slog logger
+func NewSlogLogger(logger *slog.Logger) LogfProvider {
+	return &SlogLoggerf{
+		Logger: logger,
+	}
+}
+
+// SlogLoggerf is adapter for slog to Logger interface.
+type SlogLoggerf struct {
+	Logger *slog.Logger
+}
+
+// Debugf implements Debugf method for LogfProvider interface
+func (s *SlogLoggerf) Debugf(ctx context.Context, format string, v ...any) {
+	s.Logger.DebugContext(ctx, fmt.Sprintf(format, v...))
+}
+
+// Infof implements Infof method for LogfProvider interface
+func (s SlogLoggerf) Infof(ctx context.Context, format string, v ...any) {
+	s.Logger.InfoContext(ctx, fmt.Sprintf(format, v...))
+}
+
+// Warnf implements Warnf method for LogfProvider interface
+func (s SlogLoggerf) Warnf(ctx context.Context, format string, v ...any) {
+	s.Logger.WarnContext(ctx, fmt.Sprintf(format, v...))
+}
+
+// Errorf implements Errorf method for LogfProvider interface
+func (s SlogLoggerf) Errorf(ctx context.Context, format string, v ...any) {
+	s.Logger.ErrorContext(ctx, fmt.Sprintf(format, v...))
+}
+
 // Metrics
 
 // MetricsProvider is an interface for passing library metrics to your prometheus/graphite and other metrics
diff --git a/providers_test.go b/providers_test.go
index 8a7a809..817696c 100644
--- a/providers_test.go
+++ b/providers_test.go
@@ -2,6 +2,8 @@ package vshard_router_test
 
 import (
 	"context"
+	"log/slog"
+	"os"
 	"testing"
 	"time"
 
@@ -49,3 +51,44 @@ func TestStdoutLogger(t *testing.T) {
 		stdoutLogger.Debugf(ctx, "")
 	})
 }
+
+func TestNewSlogLogger(t *testing.T) {
+	var slogProvider vshardrouter.LogfProvider
+
+	require.NotPanics(t, func() {
+		slogProvider = vshardrouter.NewSlogLogger(nil)
+	})
+
+	require.Panics(t, func() {
+		slogProvider.Warnf(context.TODO(), "")
+	})
+}
+
+func TestSlogProvider(t *testing.T) {
+	ctx := context.Background()
+
+	// create new logger handler
+	handler := slog.NewJSONHandler(os.Stdout, &slog.HandlerOptions{
+		Level: slog.LevelError,
+	})
+	// create new SLogger instance
+	sLogger := slog.New(handler)
+
+	logProvider := vshardrouter.NewSlogLogger(sLogger)
+
+	require.NotPanics(t, func() {
+		logProvider.Infof(ctx, "test %s", "s")
+	})
+
+	require.NotPanics(t, func() {
+		logProvider.Warnf(ctx, "test %s", "s")
+	})
+
+	require.NotPanics(t, func() {
+		logProvider.Errorf(ctx, "test %s", "s")
+	})
+
+	require.NotPanics(t, func() {
+		logProvider.Debugf(ctx, "test %s", "s")
+	})
+}