[#460] Add network info cache

Signed-off-by: Marina Biryukova <m.biryukova@yadro.com>

api/cache/network_info.go

@@ -0,0 +1,65 @@
+package cache
+
+import (
+	"fmt"
+	"time"
+
+	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/internal/logs"
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/netmap"
+	"github.com/bluele/gcache"
+	"go.uber.org/zap"
+)
+
+type (
+	// NetworkInfoCache provides cache for network info.
+	NetworkInfoCache struct {
+		cache  gcache.Cache
+		logger *zap.Logger
+	}
+
+	// NetworkInfoCacheConfig stores expiration params for cache.
+	NetworkInfoCacheConfig struct {
+		Lifetime time.Duration
+		Logger   *zap.Logger
+	}
+)
+
+const (
+	DefaultNetworkInfoCacheLifetime = 1 * time.Minute
+	networkInfoCacheSize            = 1
+	networkInfoKey                  = "network_info"
+)
+
+// DefaultNetworkInfoConfig returns new default cache expiration values.
+func DefaultNetworkInfoConfig(logger *zap.Logger) *NetworkInfoCacheConfig {
+	return &NetworkInfoCacheConfig{
+		Lifetime: DefaultNetworkInfoCacheLifetime,
+		Logger:   logger,
+	}
+}
+
+// NewNetworkInfoCache creates an object of NetworkInfoCache.
+func NewNetworkInfoCache(config *NetworkInfoCacheConfig) *NetworkInfoCache {
+	gc := gcache.New(networkInfoCacheSize).LRU().Expiration(config.Lifetime).Build()
+	return &NetworkInfoCache{cache: gc, logger: config.Logger}
+}
+
+func (c *NetworkInfoCache) Get() *netmap.NetworkInfo {
+	entry, err := c.cache.Get(networkInfoKey)
+	if err != nil {
+		return nil
+	}
+
+	result, ok := entry.(netmap.NetworkInfo)
+	if !ok {
+		c.logger.Warn(logs.InvalidCacheEntryType, zap.String("actual", fmt.Sprintf("%T", entry)),
+			zap.String("expected", fmt.Sprintf("%T", result)))
+		return nil
+	}
+
+	return &result
+}
+
+func (c *NetworkInfoCache) Put(info netmap.NetworkInfo) error {
+	return c.cache.Set(networkInfoKey, info)
+}