delete by prefix

cache.go

@@ -6,6 +6,7 @@ import (
 	"io"
 	"os"
 	"runtime"
+	"strings"
 	"sync"
 	"time"
 )
@@ -947,6 +948,24 @@ func (c *cache) DeleteExpired() {
 	}
 }
 
+// Delete the keys with some prefix from the cache
+func (c *cache) DeleteByPrefix(prefix string) {
+	var evictedItems []keyAndValue
+	c.mu.Lock()
+	for k := range c.items {
+		if strings.HasPrefix(k, prefix) {
+			ov, evicted := c.delete(k)
+			if evicted {
+				evictedItems = append(evictedItems, keyAndValue{k, ov})
+			}
+		}
+	}
+	c.mu.Unlock()
+	for _, v := range evictedItems {
+		c.onEvicted(v.key, v.value)
+	}
+}
+
 // Sets an (optional) function that is called with the key and value when an
 // item is evicted from the cache. (Including when it is deleted manually, but
 // not when it is overwritten.) Set to nil to disable.

cache_test.go

@@ -1150,6 +1150,26 @@ func TestDelete(t *testing.T) {
 	}
 }
 
+func TestDeleteByPrefix(t *testing.T) {
+	tc := New(DefaultExpiration, 0)
+	keys := []string{"foo", "fooa", "foo1", "fooA"}
+	for _, k := range keys {
+		tc.Set(k, "value", DefaultExpiration)
+	}
+	tc.Set("bar", "value", DefaultExpiration)
+	tc.DeleteByPrefix("foo")
+	for _, k := range keys {
+		x, found := tc.Get(k)
+		if found || x != nil {
+			t.Errorf("%s was found, but it should have been deleted\n", k)
+		}
+	}
+	x, found := tc.Get("bar")
+	if !found || x == nil {
+		t.Error("bar was not found")
+	}
+}
+
 func TestItemCount(t *testing.T) {
 	tc := New(DefaultExpiration, 0)
 	tc.Set("foo", "1", DefaultExpiration)