Add: RetrieveAndExtend to session manager

Add session sliding support to the session manager. Moved from SLS to v2 so that users can use this functionality from BL.

Closes https://corelab.mkcl.org/MKCLOS/coreosv3/corestudio/issues/446

sessionmanagermdl/sessionmanager.go

@@ -122,6 +122,40 @@ func Retrieve(key string) (Entry, error) {
 	}
 }
 
+// RetrieveAndExtend returns the entry and extends the entry expiration by provided `SECONDS`, only if remaining time < extendBy.
+// If extendBy < 0, it is same as Retrieve function.
+func RetrieveAndExtend(key string, extendBy int64) (Entry, error) {
+	entry, err := Retrieve(key)
+	if err != nil {
+		return Entry{}, err
+	}
+
+	if extendBy > 0 {
+		timeRemaining := entry.ExpiredAT - time.Now().Unix()
+
+		if timeRemaining < extendBy {
+			// update with new expiratin
+			entry.ExpiredAT = time.Now().Add(time.Second * time.Duration(extendBy)).Unix()
+
+			Store(key, entry)
+		}
+	}
+
+	return entry, nil
+}
+
+// RetrieveAndDelete deletes the entry after first retrieval
+func RetrieveAndDelete(key string) (Entry, error) {
+	entry, err := Retrieve(key)
+	if err != nil {
+		return Entry{}, err
+	}
+
+	store.Delete(key)
+
+	return entry, nil
+}
+
 // Delete removes the entry from session manager. If the key is not present, error `ErrSessionNotFound` will be thrown. Caller can ignore error if this is acceptable.
 func Delete(key string) error {
 	_, ok := store.Get(key)