cache增加带Context版本，开放平台相关接口支持Context版本 (#653)

cache/cache.go

@@ -1,6 +1,9 @@
 package cache
 
-import "time"
+import (
+	"context"
+	"time"
+)
 
 // Cache interface
 type Cache interface {
@@ -9,3 +12,44 @@ type Cache interface {
 	IsExist(key string) bool
 	Delete(key string) error
 }
+
+// ContextCache interface
+type ContextCache interface {
+	Cache
+	GetContext(ctx context.Context, key string) interface{}
+	SetContext(ctx context.Context, key string, val interface{}, timeout time.Duration) error
+	IsExistContext(ctx context.Context, key string) bool
+	DeleteContext(ctx context.Context, key string) error
+}
+
+// GetContext get value from cache
+func GetContext(ctx context.Context, cache Cache, key string) interface{} {
+	if cache, ok := cache.(ContextCache); ok {
+		return cache.GetContext(ctx, key)
+	}
+	return cache.Get(key)
+}
+
+// SetContext set value to cache
+func SetContext(ctx context.Context, cache Cache, key string, val interface{}, timeout time.Duration) error {
+	if cache, ok := cache.(ContextCache); ok {
+		return cache.SetContext(ctx, key, val, timeout)
+	}
+	return cache.Set(key, val, timeout)
+}
+
+// IsExistContext check value exists in cache.
+func IsExistContext(ctx context.Context, cache Cache, key string) bool {
+	if cache, ok := cache.(ContextCache); ok {
+		return cache.IsExistContext(ctx, key)
+	}
+	return cache.IsExist(key)
+}
+
+// DeleteContext delete value in cache.
+func DeleteContext(ctx context.Context, cache Cache, key string) error {
+	if cache, ok := cache.(ContextCache); ok {
+		return cache.DeleteContext(ctx, key)
+	}
+	return cache.Delete(key)
+}