Fixed linter issues

Signed-off-by: Marco Pracucci <[email protected]>

pkg/cacheutil/memcached_client.go

@@ -3,6 +3,7 @@ package cacheutil
 import (
 	"context"
 	"errors"
+	"fmt"
 	"sync"
 	"time"
 
@@ -219,11 +220,15 @@ func (c *memcachedClient) Stop() {
 
 func (c *memcachedClient) SetAsync(key string, value []byte, ttl time.Duration) error {
 	return c.enqueueAsync(func() {
-		c.client.Set(&memcache.Item{
+		err := c.client.Set(&memcache.Item{
 			Key:        key,
 			Value:      value,
 			Expiration: int32(time.Now().Add(ttl).Unix()),
 		})
+
+		if err != nil {
+			level.Warn(c.logger).Log("msg", fmt.Sprintf("failed to store item with key %s to memcached", key), "err", err)
+		}
 	})
 }
 

pkg/cacheutil/memcached_client_test.go

@@ -59,8 +59,11 @@ func TestMemcachedClient_SetAsync(t *testing.T) {
 	testutil.Ok(t, err)
 	defer client.Stop()
 
-	client.SetAsync("key-1", []byte("value-1"), time.Second)
-	client.SetAsync("key-2", []byte("value-2"), time.Second)
+	err = client.SetAsync("key-1", []byte("value-1"), time.Second)
+	testutil.Ok(t, err)
+
+	err = client.SetAsync("key-2", []byte("value-2"), time.Second)
+	testutil.Ok(t, err)
 
 	err = backendMock.waitItems(2)
 	testutil.Ok(t, err)
@@ -200,7 +203,8 @@ func TestMemcachedClient_GetMulti(t *testing.T) {
 
 			// Populate memcached with the initial items.
 			for _, item := range testData.initialItems {
-				client.SetAsync(item.Key, item.Value, time.Second)
+				err := client.SetAsync(item.Key, item.Value, time.Second)
+				testutil.Ok(t, err)
 			}
 
 			// Wait until initial items have been added.
@@ -212,7 +216,7 @@ func TestMemcachedClient_GetMulti(t *testing.T) {
 			testutil.Equals(t, testData.expectedHits, hits)
 			testutil.Equals(t, testData.expectedErr, err)
 
-			// Ensure the client has interected with the backend as expected.
+			// Ensure the client has interacted with the backend as expected.
 			backendMock.lock.Lock()
 			defer backendMock.lock.Unlock()
 			testutil.Equals(t, testData.expectedGetMultiCount, backendMock.getMultiCount)
@@ -251,7 +255,7 @@ func (c *memcachedClientBackendMock) GetMulti(keys []string) (map[string]*memcac
 		return nil, errors.New("mocked GetMulti error")
 	}
 
-	items := make(map[string]*memcache.Item, 0)
+	items := make(map[string]*memcache.Item)
 	for _, key := range keys {
 		if item, ok := c.items[key]; ok {
 			items[key] = item

pkg/cacheutil/memcached_server_selector.go

@@ -12,7 +12,8 @@ import (
 var (
 	addrsPool = sync.Pool{
 		New: func() interface{} {
-			return make([]net.Addr, 0, 64)
+			addrs := make([]net.Addr, 0, 64)
+			return &addrs
 		},
 	}
 )
@@ -57,27 +58,34 @@ func (s *MemcachedJumpHashSelector) SetServers(servers ...string) error {
 func (s *MemcachedJumpHashSelector) PickServer(key string) (net.Addr, error) {
 	// Unfortunately we can't read the list of server addresses from
 	// the original implementation, so we use Each() to fetch all of them.
-	addrs := addrsPool.Get().([]net.Addr)
-	s.servers.Each(func(addr net.Addr) error {
+	addrs := *(addrsPool.Get().(*[]net.Addr))
+	err := s.servers.Each(func(addr net.Addr) error {
 		addrs = append(addrs, addr)
 		return nil
 	})
 
+	if err != nil {
+		return nil, err
+	}
+
 	// No need of a jump hash in case of 0 or 1 servers.
 	if len(addrs) == 0 {
-		addrsPool.Put(addrs[:0])
+		addrs = (addrs)[:0]
+		addrsPool.Put(&addrs)
 		return nil, memcache.ErrNoServers
 	} else if len(addrs) == 1 {
-		addrsPool.Put(addrs[:0])
-		return addrs[0], nil
+		addrs = (addrs)[:0]
+		addrsPool.Put(&addrs)
+		return (addrs)[0], nil
 	}
 
 	// Pick a server using the jump hash.
 	cs := xxhash.Sum64String(key)
 	idx := JumpHash(cs, len(addrs))
-	picked := addrs[idx]
+	picked := (addrs)[idx]
 
-	addrsPool.Put(addrs[:0])
+	addrs = (addrs)[:0]
+	addrsPool.Put(&addrs)
 
 	return picked, nil
 }

pkg/cacheutil/memcached_server_selector_test.go

@@ -60,11 +60,12 @@ func TestMemcachedJumpHashSelector_Each_ShouldRespectServersOrdering(t *testing.
 		testutil.Ok(t, err)
 
 		actual := make([]string, 0, 3)
-		s.Each(func(addr net.Addr) error {
+		err = s.Each(func(addr net.Addr) error {
 			actual = append(actual, addr.String())
 			return nil
 		})
 
+		testutil.Ok(t, err)
 		testutil.Equals(t, test.expected, actual)
 	}
 }
@@ -170,11 +171,17 @@ func BenchmarkMemcachedJumpHashSelector_PickServer(b *testing.B) {
 	}
 
 	selector := MemcachedJumpHashSelector{}
-	selector.SetServers(servers...)
+	err := selector.SetServers(servers...)
+	if err != nil {
+		b.Error(err)
+	}
 
 	b.ResetTimer()
 
 	for i := 0; i < b.N; i++ {
-		selector.PickServer(string(i))
+		_, err := selector.PickServer(string(i))
+		if err != nil {
+			b.Error(err)
+		}
 	}
 }