dragonfly/pkg/rpc/cdnsystem/client/piece_seed_stream.go

149 lines
4.0 KiB
Go

/*
* Copyright 2020 The Dragonfly Authors
*
* Licensed 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 client
import (
"context"
"io"
logger "d7y.io/dragonfly/v2/internal/dflog"
"d7y.io/dragonfly/v2/pkg/rpc"
"d7y.io/dragonfly/v2/pkg/rpc/cdnsystem"
"github.com/pkg/errors"
"google.golang.org/grpc"
"google.golang.org/grpc/codes"
"google.golang.org/grpc/status"
)
type PieceSeedStream struct {
// client for one target
sc *cdnClient
ctx context.Context
hashKey string
sr *cdnsystem.SeedRequest
opts []grpc.CallOption
// stream for one client
stream cdnsystem.Seeder_ObtainSeedsClient
// server list which cannot serve
failedServers []string
rpc.RetryMeta
}
func newPieceSeedStream(ctx context.Context, sc *cdnClient, hashKey string, sr *cdnsystem.SeedRequest, opts []grpc.CallOption) (*PieceSeedStream, error) {
pss := &PieceSeedStream{
sc: sc,
ctx: ctx,
hashKey: hashKey,
sr: sr,
opts: opts,
RetryMeta: rpc.RetryMeta{
MaxAttempts: 5,
InitBackoff: 0.5,
MaxBackOff: 4.0,
},
}
if err := pss.initStream(); err != nil {
return nil, err
}
return pss, nil
}
func (pss *PieceSeedStream) initStream() error {
stream, err := rpc.ExecuteWithRetry(func() (interface{}, error) {
client, cdnServerNode, err := pss.sc.getCdnClient(pss.hashKey, false)
if err != nil {
return nil, err
}
logger.WithTaskID(pss.hashKey).Infof("invoke cdn node %s ObtainSeeds", cdnServerNode)
return client.ObtainSeeds(pss.ctx, pss.sr, pss.opts...)
}, pss.InitBackoff, pss.MaxBackOff, pss.MaxAttempts, nil)
if err == nil {
pss.stream = stream.(cdnsystem.Seeder_ObtainSeedsClient)
pss.StreamTimes = 1
}
if err != nil {
err = pss.replaceClient(pss.hashKey, err)
}
return err
}
func (pss *PieceSeedStream) Recv() (ps *cdnsystem.PieceSeed, err error) {
pss.sc.UpdateAccessNodeMapByHashKey(pss.hashKey)
if ps, err = pss.stream.Recv(); err != nil && err != io.EOF {
ps, err = pss.retryRecv(err)
}
return
}
func (pss *PieceSeedStream) retryRecv(cause error) (*cdnsystem.PieceSeed, error) {
if status.Code(cause) == codes.DeadlineExceeded {
return nil, cause
}
if err := pss.replaceStream(pss.hashKey, cause); err != nil {
if err := pss.replaceClient(pss.hashKey, cause); err != nil {
return nil, cause
}
}
return pss.Recv()
}
func (pss *PieceSeedStream) replaceStream(key string, cause error) error {
if pss.StreamTimes >= pss.MaxAttempts {
return errors.New("times of replacing stream reaches limit")
}
stream, err := rpc.ExecuteWithRetry(func() (interface{}, error) {
client, _, err := pss.sc.getCdnClient(key, true)
if err != nil {
return nil, err
}
return client.ObtainSeeds(pss.ctx, pss.sr, pss.opts...)
}, pss.InitBackoff, pss.MaxBackOff, pss.MaxAttempts, cause)
if err == nil {
pss.stream = stream.(cdnsystem.Seeder_ObtainSeedsClient)
pss.StreamTimes++
}
return err
}
func (pss *PieceSeedStream) replaceClient(key string, cause error) error {
preNode, err := pss.sc.TryMigrate(key, cause, pss.failedServers)
if err != nil {
return err
}
pss.failedServers = append(pss.failedServers, preNode)
stream, err := rpc.ExecuteWithRetry(func() (interface{}, error) {
client, _, err := pss.sc.getCdnClient(key, true)
if err != nil {
return nil, err
}
return client.ObtainSeeds(pss.ctx, pss.sr, pss.opts...)
}, pss.InitBackoff, pss.MaxBackOff, pss.MaxAttempts, cause)
if err == nil {
pss.stream = stream.(cdnsystem.Seeder_ObtainSeedsClient)
pss.StreamTimes = 1
}
if err != nil {
err = pss.replaceClient(key, cause)
}
return err
}