From acb9f9780641bdcfc097b221f1ec56f876ea912e Mon Sep 17 00:00:00 2001
From: derfenix <derfenix@gmail.com>
Date: Thu, 24 Aug 2023 23:53:52 +0300
Subject: [PATCH] Improve caching, move mutex to the cache implementation

---
 adapters/inmemorycache/cache.go     | 41 +++++++++++++++++++++++++----
 application/application.go          |  2 +-
 application/repository/logs.go      | 21 +--------------
 application/repository/logs_test.go |  6 +++--
 4 files changed, 42 insertions(+), 28 deletions(-)

diff --git a/adapters/inmemorycache/cache.go b/adapters/inmemorycache/cache.go
index 0693a9b..841adfd 100644
--- a/adapters/inmemorycache/cache.go
+++ b/adapters/inmemorycache/cache.go
@@ -1,11 +1,42 @@
 package inmemorycache
 
-type Cache map[uint64][]string
+import (
+	"sync"
+)
 
-func (c Cache) Get(id uint64) []string {
-	return c[id]
+func NewCache() *Cache {
+	return &Cache{cache: map[uint64][]string{}}
 }
 
-func (c Cache) Append(id uint64, ip string) {
-	c[id] = append(c[id], ip)
+type Cache struct {
+	cache map[uint64][]string
+	mu    sync.RWMutex
+}
+
+func (c *Cache) Get(id uint64) []string {
+	c.mu.RLock()
+	defer c.mu.RUnlock()
+
+	return c.cache[id]
+}
+
+func (c *Cache) Append(id uint64, ip string) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	if ips := c.cache[id]; len(ips) == 0 {
+		c.cache[id] = append(c.cache[id], ip)
+
+		return
+	}
+
+	for _, s := range c.cache[id] {
+		if s == ip {
+			return
+		}
+	}
+
+	c.cache[id] = append(c.cache[id], ip)
+
+	return
 }
diff --git a/application/application.go b/application/application.go
index 34270a3..3c75a76 100644
--- a/application/application.go
+++ b/application/application.go
@@ -20,7 +20,7 @@ func NewApplication(ctx context.Context, cfg Config, logger *zap.Logger) (*Appli
 		return nil, fmt.Errorf("new db: %w", err)
 	}
 
-	cache := make(inmemorycache.Cache)
+	cache := inmemorycache.NewCache()
 
 	repo, err := repository.NewConnLogs(ctx, db, cache, logger, cfg.UpdateInterval)
 	if err != nil {
diff --git a/application/repository/logs.go b/application/repository/logs.go
index 7fb3a6b..b56f620 100644
--- a/application/repository/logs.go
+++ b/application/repository/logs.go
@@ -4,7 +4,6 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-	"sync"
 	"time"
 
 	"github.com/uptrace/bun"
@@ -57,7 +56,6 @@ func NewConnLogs(ctx context.Context, db *bun.DB, cache Cache, logger *zap.Logge
 
 type ConnLogs struct {
 	db     *bun.DB
-	mu     sync.RWMutex
 	cache  Cache
 	lastTS time.Time
 }
@@ -65,9 +63,6 @@ type ConnLogs struct {
 func (l *ConnLogs) fillCache(ctx context.Context) error {
 	var entity []ConnLog
 
-	l.mu.Lock()
-	defer l.mu.Unlock()
-
 	query := l.db.NewSelect().Model(&entity).
 		Order("ts").
 		Group("user_id", "ip_addr").
@@ -82,22 +77,8 @@ func (l *ConnLogs) fillCache(ctx context.Context) error {
 		return fmt.Errorf("select: %w", err)
 	}
 
-loop:
 	for i := range entity {
-		item := &entity[i]
-
-		if ips := l.cache.Get(item.UserID); len(ips) == 0 {
-			l.cache.Append(item.UserID, item.IP)
-			continue
-		}
-
-		for _, s := range l.cache.Get(item.UserID) {
-			if s == item.IP {
-				continue loop
-			}
-		}
-
-		l.cache.Append(item.UserID, item.IP)
+		l.cache.Append(entity[i].UserID, entity[i].IP)
 	}
 
 	if len(entity) > 0 {
diff --git a/application/repository/logs_test.go b/application/repository/logs_test.go
index e0ae95d..367698b 100644
--- a/application/repository/logs_test.go
+++ b/application/repository/logs_test.go
@@ -70,7 +70,9 @@ func TestLogs_Get(t *testing.T) {
 	})
 	require.NoError(t, err)
 
-	ctx := context.Background()
+	ctx, cancel := context.WithCancel(context.Background())
+	t.Cleanup(cancel)
+
 	logger := zaptest.NewLogger(t)
 
 	require.NoError(t, application.Migrate(ctx, db, logger))
@@ -96,7 +98,7 @@ func TestLogs_Get(t *testing.T) {
 	_, err = db.NewInsert().Model(&testData).Exec(ctx)
 	require.NoError(t, err)
 
-	repo, err := NewConnLogs(ctx, db, make(inmemorycache.Cache), logger, time.Millisecond*100)
+	repo, err := NewConnLogs(ctx, db, inmemorycache.NewCache(), logger, time.Millisecond*100)
 	require.NoError(t, err)
 
 	t.Run("found dup", func(t *testing.T) {