kinesis-consumer/buffers.go
Harlow Ward b086b64d7b Add Emitters
* Add first s3 Emitter along with Emitter Interface.
* Replace setters with initializers.
2014-07-29 19:02:16 -07:00

69 lines
1.4 KiB
Go

package etl
import "bytes"
type Buffer interface {
Data() []byte
FirstSequenceNumber() string
LastSequenceNumber() string
NumMessagesInBuffer() int
}
type MsgBuffer struct {
buffer bytes.Buffer
firstSequenceNumber string
lastSequenceNumber string
numMessagesToBuffer int
sequencesInBuffer []string
}
func (b MsgBuffer) NumMessagesToBuffer() int {
return b.numMessagesToBuffer
}
func (b *MsgBuffer) ConsumeRecord(data []byte, sequenceNumber string) {
if len(b.sequencesInBuffer) == 0 {
b.firstSequenceNumber = sequenceNumber
}
b.lastSequenceNumber = sequenceNumber
if !b.SequenceExists(sequenceNumber) {
b.buffer.Write(data)
b.sequencesInBuffer = append(b.sequencesInBuffer, sequenceNumber)
}
}
func (b MsgBuffer) SequenceExists(sequenceNumber string) bool {
for _, v := range b.sequencesInBuffer {
if v == sequenceNumber {
return true
}
}
return false
}
func (b MsgBuffer) Data() []byte {
return b.buffer.Bytes()
}
func (b MsgBuffer) NumMessagesInBuffer() int {
return len(b.sequencesInBuffer)
}
func (b *MsgBuffer) FlushBuffer() {
b.buffer.Reset()
b.sequencesInBuffer = b.sequencesInBuffer[:0]
}
func (b MsgBuffer) ShouldFlush() bool {
return len(b.sequencesInBuffer) >= b.NumMessagesToBuffer()
}
func (b MsgBuffer) LastSequenceNumber() string {
return b.lastSequenceNumber
}
func (b MsgBuffer) FirstSequenceNumber() string {
return b.firstSequenceNumber
}