MM-21210: Add LRU cache for ChannelStore.GetMembersForUser (#13593)

Automatic Merge

services/cache/cache.go

@@ -31,6 +31,9 @@ type Cache interface {
 	// Remove deletes the value for a key.
 	Remove(key interface{})
 
+	// RemoveByPrefix deletes all keys containing the given prefix string.
+	RemoveByPrefix(prefix string)
+
 	// Keys returns a slice of the keys in the cache.
 	Keys() []interface{}
 

services/cache/lru/lru.go

@@ -12,6 +12,7 @@ package lru
 
 import (
 	"container/list"
+	"strings"
 	"sync"
 	"time"
 
@@ -187,6 +188,24 @@ func (c *Cache) Remove(key interface{}) {
 	}
 }
 
+// RemoveByPrefix deletes all keys containing the given prefix string.
+func (c *Cache) RemoveByPrefix(prefix string) {
+	c.lock.Lock()
+	defer c.lock.Unlock()
+
+	for ent := c.evictList.Back(); ent != nil; ent = ent.Prev() {
+		e := ent.Value.(*entry)
+		if e.generation == c.currentGeneration {
+			keyString := e.key.(string)
+			if strings.HasPrefix(keyString, prefix) {
+				if ent, ok := c.items[e.key]; ok {
+					c.removeElement(ent)
+				}
+			}
+		}
+	}
+}
+
 // Keys returns a slice of the keys in the cache, from oldest to newest.
 func (c *Cache) Keys() []interface{} {
 	c.lock.RLock()