More efficient content hash fetch

peer/cwtch_peer.go

@@ -1193,7 +1193,11 @@ func (cp *cwtchPeer) GetChannelMessageBySignature(conversationID int, channelID
 func (cp *cwtchPeer) GetChannelMessageByContentHash(conversationID int, channelID int, contenthash string) (int, error) {
 	cp.mutex.Lock()
 	defer cp.mutex.Unlock()
-	return cp.storage.GetChannelMessageByContentHash(conversationID, channelID, contenthash)
+	messageID, err := cp.storage.GetChannelMessageByContentHash(conversationID, channelID, contenthash)
+	if err == nil {
+		return cp.storage.GetRowNumberByMessageID(conversationID, channelID, messageID)
+	}
+	return -1, err
 }
 
 // constructGroupFromConversation returns a model.Group wrapper around a database back groups. Useful for

peer/cwtchprofilestorage.go

@@ -52,6 +52,7 @@ type CwtchProfileStorage struct {
 	channelGetCountStmts                map[ChannelID]*sql.Stmt
 	channelGetMostRecentMessagesStmts   map[ChannelID]*sql.Stmt
 	channelGetMessageByContentHashStmts map[ChannelID]*sql.Stmt
+	channelRowNumberStmts               map[ChannelID]*sql.Stmt
 	ProfileDirectory                    string
 	db                                  *sql.DB
 }
@@ -95,6 +96,9 @@ const getMessageBySignatureFromConversationSQLStmt = `select ID from channel_%d_
 // getMessageByContentHashFromConversationSQLStmt is a template for selecting conversation messages by content hash
 const getMessageByContentHashFromConversationSQLStmt = `select ID from channel_%d_%d_chat where ContentHash=(?) order by ID desc limit 1;`
 
+// getLocalIndexOfMessageIdSQLStmt is a template for fetching the offset of a message from the bottom of the database.
+const getLocalIndexOfMessageIdSQLStmt = `select count (*) from channel_%d_%d_chat where ID >= (?) order by ID desc;`
+
 // getMessageCountFromConversationSQLStmt is a template for fetching the count of a messages  in a conversation channel
 const getMessageCountFromConversationSQLStmt = `select count(*) from channel_%d_%d_chat;`
 
@@ -187,7 +191,9 @@ func NewCwtchProfileStorage(db *sql.DB, profileDirectory string) (*CwtchProfileS
 			channelGetMessageBySignatureStmts:   map[ChannelID]*sql.Stmt{},
 			channelGetMessageByContentHashStmts: map[ChannelID]*sql.Stmt{},
 			channelGetMostRecentMessagesStmts:   map[ChannelID]*sql.Stmt{},
-			channelGetCountStmts:                map[ChannelID]*sql.Stmt{}},
+			channelGetCountStmts:                map[ChannelID]*sql.Stmt{},
+			channelRowNumberStmts:               map[ChannelID]*sql.Stmt{},
+		},
 		nil
 }
 
@@ -530,9 +536,48 @@ func (cps *CwtchProfileStorage) GetChannelMessageByContentHash(conversation int,
 		return -1, err
 	}
 	rows.Close()
+
 	return id, nil
 }
 
+// GetRowNumberByMessageID looks up the row number of a message by the message ID
+func (cps *CwtchProfileStorage) GetRowNumberByMessageID(conversation int, channel int, id int) (int, error) {
+	channelID := ChannelID{Conversation: conversation, Channel: channel}
+
+	_, exists := cps.channelRowNumberStmts[channelID]
+	if !exists {
+		conversationStmt, err := cps.db.Prepare(fmt.Sprintf(getLocalIndexOfMessageIdSQLStmt, conversation, channel))
+		if err != nil {
+			log.Errorf("error executing transaction: %v", err)
+			return -1, err
+		}
+		cps.channelRowNumberStmts[channelID] = conversationStmt
+	}
+
+	rows, err := cps.channelRowNumberStmts[channelID].Query(id)
+	if err != nil {
+		log.Errorf("error executing query: %v", err)
+		return -1, err
+	}
+
+	result := rows.Next()
+
+	if !result {
+		return -1, errors.New("no result found")
+	}
+
+	var rownum int
+	err = rows.Scan(&rownum)
+	if err != nil {
+		log.Errorf("error fetching rows: %v", err)
+		rows.Close()
+		return -1, err
+	}
+	rows.Close()
+
+	return rownum, nil
+}
+
 // GetChannelMessage looks up a channel message by conversation, channel and message id. On success it
 // returns the message body and the attributes associated with the message. Otherwise an error is returned.
 func (cps *CwtchProfileStorage) GetChannelMessage(conversation int, channel int, messageID int) (string, model.Attributes, error) {
@@ -636,6 +681,16 @@ func (cps *CwtchProfileStorage) GetMostRecentMessages(conversation int, channel
 	}
 }
 
+func (cps *CwtchProfileStorage) PurgeConversationChannel(conversation int, channel int) error {
+	conversationStmt, err := cps.db.Prepare(fmt.Sprintf(purgeMessagesFromConversationSQLStmt, conversation, channel))
+	if err != nil {
+		log.Errorf("error executing transaction: %v", err)
+		return err
+	}
+	conversationStmt.Exec()
+	return conversationStmt.Close()
+}
+
 // Close closes the underlying database and prepared statements
 func (cps *CwtchProfileStorage) Close() {
 	if cps.db != nil {
@@ -648,11 +703,7 @@ func (cps *CwtchProfileStorage) Close() {
 					if conversation.Attributes[event.SaveHistoryKey] != event.SaveHistoryConfirmed {
 						log.Infof("purging conversation...")
 						// TODO: At some point in the future this needs to iterate over channels and make a decision for each on..
-						conversationStmt, err := cps.db.Prepare(fmt.Sprintf(purgeMessagesFromConversationSQLStmt, conversation.ID, 0))
-						if err != nil {
-							log.Errorf("error executing transaction: %v", err)
-						}
-						conversationStmt.Exec()
+						cps.PurgeConversationChannel(conversation.ID, 0)
 					}
 				}
 			}