Zhen Ye d3e32bb599
enhance: make pchannel level flusher (#39275)
issue: #38399

- Add a pchannel level checkpoint for flush processing
- Refactor the recovery of flushers of wal
- make a shared wal scanner first, then make multi datasyncservice on it

Signed-off-by: chyezh <chyezh@outlook.com>
2025-02-10 16:32:45 +08:00

48 lines
1.7 KiB
Go

package wal
import (
"github.com/cockroachdb/errors"
"github.com/milvus-io/milvus/pkg/streaming/util/message"
"github.com/milvus-io/milvus/pkg/streaming/util/options"
"github.com/milvus-io/milvus/pkg/streaming/util/types"
)
type MessageFilter = func(message.ImmutableMessage) bool
var ErrUpstreamClosed = errors.New("upstream closed")
// ReadOption is the option for reading records from the wal.
type ReadOption struct {
VChannel string // vchannel is a optional field to select a vchannel to consume.
// If the vchannel is setup, the message that is not belong to these vchannel will be dropped by scanner.
// Otherwise all message on WAL will be sent.
DeliverPolicy options.DeliverPolicy
MessageFilter []options.DeliverFilter
MesasgeHandler message.Handler // message handler for message processing.
// If the message handler is nil (no redundant operation need to apply),
// the default message handler will be used, and the receiver will be returned from Chan.
// Otherwise, Chan will panic.
// vaild every message will be passed to this handler before being delivered to the consumer.
}
// Scanner is the interface for reading records from the wal.
type Scanner interface {
// Chan returns the channel of message if Option.MessageHandler is nil.
Chan() <-chan message.ImmutableMessage
// Channel returns the channel assignment info of the wal.
Channel() types.PChannelInfo
// Error returns the error of scanner failed.
// Will block until scanner is closed or Chan is dry out.
Error() error
// Done returns a channel which will be closed when scanner is finished or closed.
Done() <-chan struct{}
// Close the scanner, release the underlying resources.
// Return the error same with `Error`
Close() error
}