openreplay/backend/pkg/messages/session-iterator.go
Alexander 44d550ca3e
Remove message index from mob file (#1213)
* feat(backend): removed message index from mob file messages

* feat(backend): remove duplicated messages (by message index)

* feat(backend): added MAX_INDEX at the begining of session to indicate a new version of mob file

* feat(backend): added comments to code
2023-04-26 12:33:51 +02:00

89 lines
2.1 KiB
Go

package messages
import (
"bytes"
"fmt"
"io"
"log"
"sort"
)
type msgInfo struct {
index uint64
start int64
end int64
body Message
msgType uint64
}
func (m *msgInfo) Print() string {
return fmt.Sprintf("index: %d, start: %d, end: %d, type: %d, body: %s", m.index, m.start, m.end, m.msgType, m.body)
}
func SplitMessages(data []byte) ([]*msgInfo, error) {
messages := make([]*msgInfo, 0)
indexes := make(map[uint64]bool)
reader := NewBytesReader(data)
for {
// Get message start
msgStart := reader.Pointer()
if int(msgStart) >= len(data) {
return messages, nil
}
// Read message index
msgIndex, err := reader.ReadIndex()
if err != nil {
if err != io.EOF {
log.Println(reader.Pointer(), msgStart)
return messages, fmt.Errorf("read message index err: %s", err)
}
return messages, nil
}
// Read message type
msgType, err := reader.ReadUint()
if err != nil {
return messages, fmt.Errorf("read message type err: %s", err)
}
// Read message body
body, err := ReadMessage(msgType, reader)
if err != nil {
return messages, fmt.Errorf("read message body err: %s", err)
}
if _, ok := indexes[msgIndex]; ok {
log.Printf("duplicate message index: %d", msgIndex)
continue
}
indexes[msgIndex] = true
// Add new message info to messages slice
messages = append(messages, &msgInfo{
index: msgIndex,
start: msgStart,
end: reader.Pointer(),
body: body,
msgType: msgType,
})
}
}
func SortMessages(messages []*msgInfo) []*msgInfo {
sort.SliceStable(messages, func(i, j int) bool {
return messages[i].index < messages[j].index
})
return messages
}
func MergeMessages(data []byte, messages []*msgInfo) []byte {
sortedSession := bytes.NewBuffer(make([]byte, 0, len(data)))
// Add maximum possible index value to the start of the session to inform player about new version of mob file
sortedSession.Write([]byte{0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff})
for _, info := range messages {
// Write message without index (that's why we use +8)
sortedSession.Write(data[info.start+8 : info.end])
}
return sortedSession.Bytes()
}