github.com/matrixorigin/matrixone@v0.7.0/pkg/vm/engine/tae/logtail/service/client.go (about)

     1  // Copyright 2021 Matrix Origin
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //	http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package service
    16  
    17  import (
    18  	"context"
    19  
    20  	"go.uber.org/ratelimit"
    21  
    22  	"github.com/matrixorigin/matrixone/pkg/common/moerr"
    23  	"github.com/matrixorigin/matrixone/pkg/common/morpc"
    24  	"github.com/matrixorigin/matrixone/pkg/pb/api"
    25  	"github.com/matrixorigin/matrixone/pkg/pb/logtail"
    26  )
    27  
    28  type ClientOption func(*LogtailClient)
    29  
    30  func WithClientRequestPerSecond(rps int) ClientOption {
    31  	return func(c *LogtailClient) {
    32  		c.options.rps = rps
    33  	}
    34  }
    35  
    36  // LogtailClient encapsulates morpc stream.
    37  type LogtailClient struct {
    38  	stream   morpc.Stream
    39  	recvChan chan morpc.Message
    40  
    41  	options struct {
    42  		rps int
    43  	}
    44  
    45  	limiter ratelimit.Limiter
    46  }
    47  
    48  // NewLogtailClient constructs LogtailClient.
    49  func NewLogtailClient(stream morpc.Stream, opts ...ClientOption) (*LogtailClient, error) {
    50  	client := &LogtailClient{
    51  		stream: stream,
    52  	}
    53  
    54  	recvChan, err := stream.Receive()
    55  	if err != nil {
    56  		return nil, err
    57  	}
    58  	client.recvChan = recvChan
    59  
    60  	client.options.rps = 200
    61  	for _, opt := range opts {
    62  		opt(client)
    63  	}
    64  	client.limiter = ratelimit.New(client.options.rps)
    65  
    66  	return client, nil
    67  }
    68  
    69  // Close closes stream.
    70  func (c *LogtailClient) Close() error {
    71  	return c.stream.Close()
    72  }
    73  
    74  // Subscribe subscribes table.
    75  func (c *LogtailClient) Subscribe(
    76  	ctx context.Context, table api.TableID,
    77  ) error {
    78  	c.limiter.Take()
    79  
    80  	request := &LogtailRequest{}
    81  	request.Request = &logtail.LogtailRequest_SubscribeTable{
    82  		SubscribeTable: &logtail.SubscribeRequest{
    83  			Table: &table,
    84  		},
    85  	}
    86  	request.SetID(c.stream.ID())
    87  	return c.stream.Send(ctx, request)
    88  }
    89  
    90  // Unsubscribe cancel subscription for table.
    91  func (c *LogtailClient) Unsubscribe(
    92  	ctx context.Context, table api.TableID,
    93  ) error {
    94  	c.limiter.Take()
    95  
    96  	request := &LogtailRequest{}
    97  	request.Request = &logtail.LogtailRequest_UnsubscribeTable{
    98  		UnsubscribeTable: &logtail.UnsubscribeRequest{
    99  			Table: &table,
   100  		},
   101  	}
   102  	request.SetID(c.stream.ID())
   103  	return c.stream.Send(ctx, request)
   104  }
   105  
   106  // Receive fetches logtail response.
   107  //
   108  // 1. response for error: *LogtailResponse.GetError() != nil
   109  // 2. response for subscription: *LogtailResponse.GetSubscribeResponse() != nil
   110  // 3. response for unsubscription: *LogtailResponse.GetUnsubscribeResponse() != nil
   111  // 3. response for additional logtail: *LogtailResponse.GetUpdateResponse() != nil
   112  func (c *LogtailClient) Receive() (*LogtailResponse, error) {
   113  	recvFunc := func() (*LogtailResponseSegment, error) {
   114  		message, ok := <-c.recvChan
   115  		if !ok || message == nil {
   116  			return nil, moerr.NewStreamClosedNoCtx()
   117  		}
   118  		return message.(*LogtailResponseSegment), nil
   119  	}
   120  
   121  	prev, err := recvFunc()
   122  	if err != nil {
   123  		return nil, err
   124  	}
   125  	buf := make([]byte, 0, prev.MessageSize)
   126  	buf = AppendChunk(buf, prev.GetPayload())
   127  
   128  	for prev.Sequence < prev.MaxSequence {
   129  		segment, err := recvFunc()
   130  		if err != nil {
   131  			return nil, err
   132  		}
   133  		buf = AppendChunk(buf, segment.GetPayload())
   134  		prev = segment
   135  	}
   136  
   137  	resp := &LogtailResponse{}
   138  	if err := resp.Unmarshal(buf); err != nil {
   139  		return nil, err
   140  	}
   141  	return resp, nil
   142  }