fix statcache logic (cs3org#2440)

Signed-off-by: jkoberg <[email protected]>

Author: kobergj

Diff for: changelog/unreleased/improve_statcache.md

@@ -0,0 +1,5 @@
+Bugfix: Add ArbitraryMetadataKeys to statcache key
+
+Otherwise stating with and without them would return the same result (because it is cached)
+
+https://github.com/cs3org/reva/pull/2440

Diff for: internal/grpc/services/gateway/storageprovidercache.go

@@ -211,19 +211,24 @@ type cachedAPIClient struct {
 // generates a user specific key pointing to ref - used for statcache
 // a key looks like: uid:1234-1233!sid:5678-5677!oid:9923-9934!path:/path/to/source
 // as you see it adds "uid:"/"sid:"/"oid:" prefixes to the uuids so they can be differentiated
-func statKey(user *userpb.User, ref *provider.Reference) string {
+func statKey(user *userpb.User, ref *provider.Reference, metaDataKeys []string) string {
 	if ref == nil || ref.ResourceId == nil || ref.ResourceId.StorageId == "" {
 		return ""
 	}
 
-	return "uid" + user.Id.OpaqueId + "!sid:" + ref.ResourceId.StorageId + "!oid:" + ref.ResourceId.OpaqueId + "!path:" + ref.Path
+	key := "uid" + user.Id.OpaqueId + "!sid:" + ref.ResourceId.StorageId + "!oid:" + ref.ResourceId.OpaqueId + "!path:" + ref.Path
+	for _, k := range metaDataKeys {
+		key += "!mdk:" + k
+	}
+
+	return key
 }
 
 // Stat looks in cache first before forwarding to storage provider
 func (c *cachedAPIClient) Stat(ctx context.Context, in *provider.StatRequest, opts ...grpc.CallOption) (*provider.StatResponse, error) {
 	cache := c.caches[stat]
 
-	key := statKey(ctxpkg.ContextMustGetUser(ctx), in.Ref)
+	key := statKey(ctxpkg.ContextMustGetUser(ctx), in.Ref, in.ArbitraryMetadataKeys)
 	if key != "" {
 		s := &provider.StatResponse{}
 		if err := pullFromCache(cache, key, s); err == nil {