Version Inicial

internal/cache/cache.go

@@ -0,0 +1,83 @@
+package cache
+
+import (
+	"sync"
+	"time"
+
+	"fergalla.com/dockerbot/internal/docker"
+)
+
+type ContainerCache struct {
+	mu sync.RWMutex
+
+	data      []docker.ContainerBasicInfo
+	expiresAt time.Time
+	ttl       time.Duration
+
+	// función para obtener datos frescos
+	fetchFunc func() ([]docker.ContainerBasicInfo, error)
+}
+
+// Constructor
+func NewContainerCache(ttl time.Duration, fetch func() ([]docker.ContainerBasicInfo, error)) *ContainerCache {
+	return &ContainerCache{
+		ttl:       ttl,
+		fetchFunc: fetch,
+	}
+}
+
+// Get devuelve datos cacheados o refresca si ha expirado
+func (c *ContainerCache) Get() ([]docker.ContainerBasicInfo, error) {
+	// 🔍 lectura rápida
+	c.mu.RLock()
+	if time.Now().Before(c.expiresAt) && c.data != nil {
+		data := c.data
+		c.mu.RUnlock()
+		return data, nil
+	}
+	c.mu.RUnlock()
+
+	// 🔒 lock de escritura (refresco)
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	// ⚠️ doble check (evita refrescos duplicados)
+	if time.Now().Before(c.expiresAt) && c.data != nil {
+		return c.data, nil
+	}
+
+	data, err := c.fetchFunc()
+	if err != nil {
+		return nil, err
+	}
+
+	c.data = data
+	c.expiresAt = time.Now().Add(c.ttl)
+
+	return c.data, nil
+}
+
+// Invalidate fuerza limpieza de cache
+func (c *ContainerCache) Invalidate() {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	c.data = nil
+	c.expiresAt = time.Time{}
+}
+
+// ForceRefresh fuerza actualización inmediata
+func (c *ContainerCache) ForceRefresh() ([]docker.ContainerBasicInfo, error) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	data, err := c.fetchFunc()
+	if err != nil {
+		return nil, err
+	}
+
+	c.data = data
+	c.expiresAt = time.Now().Add(c.ttl)
+
+	return c.data, nil
+}