milvus/pkg/mq/common/message.go

103 lines
3.5 KiB
Go

// Licensed to the LF AI & Data foundation under one
// or more contributor license agreements. See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership. The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package common
import (
"fmt"
"google.golang.org/protobuf/proto"
"github.com/milvus-io/milvus-proto/go-api/v2/commonpb"
)
// ProducerOptions contains the options of a producer
type ProducerOptions struct {
// The topic that this Producer will publish
Topic string
// Enable compression
// For Pulsar, this enables ZSTD compression with default compression level
EnableCompression bool
}
// ProducerMessage contains the messages of a producer
type ProducerMessage struct {
// Payload get the payload of the message
Payload []byte
// Properties are application defined key/value pairs that will be attached to the message.
// Return the properties attached to the message.
Properties map[string]string
}
// Message is the interface that provides operations of a consumer
type Message interface {
// Topic get the topic from which this message originated from
Topic() string
// Properties are application defined key/value pairs that will be attached to the message.
// Return the properties attached to the message.
Properties() map[string]string
// Payload get the payload of the message
Payload() []byte
// ID get the unique message ID associated with this message.
// The message id can be used to univocally refer to a message without having the keep the entire payload in memory.
ID() MessageID
}
// SubscriptionInitialPosition is the type of a subscription initial position
type SubscriptionInitialPosition int
const (
// SubscriptionPositionLatest is latest position which means the start consuming position will be the last message
SubscriptionPositionLatest SubscriptionInitialPosition = iota
// SubscriptionPositionEarliest is earliest position which means the start consuming position will be the first message
SubscriptionPositionEarliest
// SubscriptionPositionUnkown indicates we don't care about the consumer location, since we are doing another seek or only some meta api over that
SubscriptionPositionUnknown
)
const MsgTypeKey = "msg_type"
func GetMsgType(msg Message) (commonpb.MsgType, error) {
msgType := commonpb.MsgType_Undefined
properties := msg.Properties()
if properties != nil {
if val, ok := properties[MsgTypeKey]; ok {
msgType = commonpb.MsgType(commonpb.MsgType_value[val])
}
}
if msgType == commonpb.MsgType_Undefined {
header := commonpb.MsgHeader{}
if msg.Payload() == nil {
return msgType, fmt.Errorf("failed to unmarshal message header, payload is empty")
}
err := proto.Unmarshal(msg.Payload(), &header)
if err != nil {
return msgType, fmt.Errorf("failed to unmarshal message header, err %s", err.Error())
}
if header.Base == nil {
return msgType, fmt.Errorf("failed to unmarshal message, header is uncomplete")
}
msgType = header.Base.MsgType
}
return msgType, nil
}