feat: GetOrSetFunc

arc.go

@@ -182,6 +182,22 @@ func (c *ARC) GetIFPresent(key interface{}) (interface{}, error) {
 	return v, err
 }
 
+// GetOrSetFunc return the value and set if the key not found.
+func (c *ARC) GetOrSetFunc(key interface{}, f func() (interface{}, error), duration time.Duration) (interface{}, error) {
+	v, err := c.Get(key)
+	if err == KeyNotFoundError {
+		value, err := f()
+		if err != nil {
+			return nil, err
+		}
+		if value == nil {
+			return nil, nil
+		}
+		return v, c.SetWithExpire(key, value, duration)
+	}
+	return v, nil
+}
+
 func (c *ARC) get(key interface{}, onLoad bool) (interface{}, error) {
 	v, err := c.getValue(key, onLoad)
 	if err != nil {

cache.go

@@ -30,6 +30,8 @@ type Cache interface {
 	// GetIFPresent returns the value for the specified key if it is present in the cache.
 	// Return KeyNotFoundError if the key is not present.
 	GetIFPresent(key interface{}) (interface{}, error)
+	// GetOrSetFunc return the value and set if the key not found.
+	GetOrSetFunc(key interface{}, f func() (interface{}, error), duration time.Duration) (interface{}, error)
 	// GetAll returns a map containing all key-value pairs in the cache.
 	GetALL(checkExpired bool) map[interface{}]interface{}
 	get(key interface{}, onLoad bool) (interface{}, error)

lfu.go

@@ -133,6 +133,22 @@ func (c *LFUCache) GetIFPresent(key interface{}) (interface{}, error) {
 	return v, err
 }
 
+// GetOrSetFunc return the value and set if the key not found.
+func (c *LFUCache) GetOrSetFunc(key interface{}, f func() (interface{}, error), duration time.Duration) (interface{}, error) {
+	v, err := c.Get(key)
+	if err == KeyNotFoundError {
+		value, err := f()
+		if err != nil {
+			return nil, err
+		}
+		if value == nil {
+			return nil, nil
+		}
+		return v, c.SetWithExpire(key, value, duration)
+	}
+	return v, nil
+}
+
 func (c *LFUCache) get(key interface{}, onLoad bool) (interface{}, error) {
 	v, err := c.getValue(key, onLoad)
 	if err != nil {

lru.go

@@ -110,6 +110,22 @@ func (c *LRUCache) GetIFPresent(key interface{}) (interface{}, error) {
 	return v, err
 }
 
+// GetOrSetFunc return the value and set if the key not found.
+func (c *LRUCache) GetOrSetFunc(key interface{}, f func() (interface{}, error), duration time.Duration) (interface{}, error) {
+	v, err := c.Get(key)
+	if err == KeyNotFoundError {
+		value, err := f()
+		if err != nil {
+			return nil, err
+		}
+		if value == nil {
+			return nil, nil
+		}
+		return v, c.SetWithExpire(key, value, duration)
+	}
+	return v, nil
+}
+
 func (c *LRUCache) get(key interface{}, onLoad bool) (interface{}, error) {
 	v, err := c.getValue(key, onLoad)
 	if err != nil {

simple.go

@@ -108,6 +108,22 @@ func (c *SimpleCache) GetIFPresent(key interface{}) (interface{}, error) {
 	return v, nil
 }
 
+// GetOrSetFunc return the value and set if the key not found.
+func (c *SimpleCache) GetOrSetFunc(key interface{}, f func() (interface{}, error), duration time.Duration) (interface{}, error) {
+	v, err := c.Get(key)
+	if err == KeyNotFoundError {
+		value, err := f()
+		if err != nil {
+			return nil, err
+		}
+		if value == nil {
+			return nil, nil
+		}
+		return v, c.SetWithExpire(key, value, duration)
+	}
+	return v, nil
+}
+
 func (c *SimpleCache) get(key interface{}, onLoad bool) (interface{}, error) {
 	v, err := c.getValue(key, onLoad)
 	if err != nil {