storj/pkg/piecestore/psserver/retrieve.go
2019-01-24 15:15:10 -05:00

213 lines
5.1 KiB
Go

// Copyright (C) 2019 Storj Labs, Inc.
// See LICENSE for copying information.
package psserver
import (
"context"
"fmt"
"io"
"os"
"sync/atomic"
"github.com/gogo/protobuf/proto"
"github.com/zeebo/errs"
"go.uber.org/zap"
"storj.io/storj/internal/sync2"
"storj.io/storj/pkg/pb"
"storj.io/storj/pkg/utils"
)
// RetrieveError is a type of error for failures in Server.Retrieve()
var RetrieveError = errs.Class("retrieve error")
// Retrieve -- Retrieve data from piecestore and send to client
func (s *Server) Retrieve(stream pb.PieceStoreRoutes_RetrieveServer) (err error) {
ctx := stream.Context()
defer mon.Task()(&ctx)(&err)
// Receive Signature
recv, err := stream.Recv()
if err != nil {
return RetrieveError.Wrap(err)
}
if recv == nil {
return RetrieveError.New("error receiving piece data")
}
authorization := recv.GetAuthorization()
if err := s.verifier(authorization); err != nil {
return ServerError.Wrap(err)
}
pd := recv.GetPieceData()
if pd == nil {
return RetrieveError.New("PieceStore message is nil")
}
s.log.Debug("Retrieving",
zap.String("Piece ID", fmt.Sprint(pd.GetId())),
zap.Int64("Offset", pd.GetOffset()),
zap.Int64("Size", pd.GetPieceSize()),
)
id, err := getNamespacedPieceID([]byte(pd.GetId()), getNamespace(authorization))
if err != nil {
return err
}
// Get path to data being retrieved
path, err := s.storage.PiecePath(id)
if err != nil {
return err
}
// Verify that the path exists
fileInfo, err := os.Stat(path)
if err != nil {
return RetrieveError.Wrap(err)
}
// Read the size specified
totalToRead := pd.GetPieceSize()
fileSize := fileInfo.Size()
// Read the entire file if specified -1 but make sure we do it from the correct offset
if pd.GetPieceSize() <= -1 || totalToRead+pd.GetOffset() > fileSize {
totalToRead = fileSize - pd.GetOffset()
}
retrieved, allocated, err := s.retrieveData(ctx, stream, id, pd.GetOffset(), totalToRead)
if err != nil {
return err
}
s.log.Info("Successfully retrieved",
zap.String("Piece ID", fmt.Sprint(pd.GetId())),
zap.Int64("Allocated", allocated),
zap.Int64("Retrieved", retrieved),
)
return nil
}
func (s *Server) retrieveData(ctx context.Context, stream pb.PieceStoreRoutes_RetrieveServer, id string, offset, length int64) (retrieved, allocated int64, err error) {
defer mon.Task()(&ctx)(&err)
storeFile, err := s.storage.Reader(ctx, id, offset, length)
if err != nil {
return 0, 0, err
}
defer utils.LogClose(storeFile)
writer := NewStreamWriter(s, stream)
allocationTracking := sync2.NewThrottle()
totalAllocated := int64(0)
// Bandwidth Allocation recv loop
go func() {
var lastTotal int64
var lastAllocation *pb.RenterBandwidthAllocation
defer func() {
if lastAllocation == nil {
return
}
err := s.DB.WriteBandwidthAllocToDB(lastAllocation)
if err != nil {
// TODO: handle error properly
s.log.Error("WriteBandwidthAllocToDB Error:", zap.Error(err))
}
}()
for {
recv, err := stream.Recv()
if err != nil {
allocationTracking.Fail(err)
return
}
alloc := recv.GetBandwidthAllocation()
allocData := &pb.RenterBandwidthAllocation_Data{}
if err = proto.Unmarshal(alloc.GetData(), allocData); err != nil {
allocationTracking.Fail(err)
return
}
if err = s.verifySignature(ctx, alloc); err != nil {
allocationTracking.Fail(err)
return
}
if allocData.GetPayerAllocation() == nil {
allocationTracking.Fail(StoreError.New("no payer bandwidth allocation"))
return
}
pbaData := &pb.PayerBandwidthAllocation_Data{}
if err = proto.Unmarshal(allocData.GetPayerAllocation().GetData(), pbaData); err != nil {
allocationTracking.Fail(err)
return
}
if err = s.verifyPayerAllocation(pbaData, "GET"); err != nil {
allocationTracking.Fail(err)
return
}
// TODO: break when lastTotal >= allocData.GetPayer_allocation().GetData().GetMax_size()
if lastTotal > allocData.GetTotal() {
allocationTracking.Fail(fmt.Errorf("got lower allocation was %v got %v", lastTotal, allocData.GetTotal()))
return
}
atomic.StoreInt64(&totalAllocated, allocData.GetTotal())
if err = allocationTracking.Produce(allocData.GetTotal() - lastTotal); err != nil {
return
}
lastAllocation = alloc
lastTotal = allocData.GetTotal()
}
}()
// Data send loop
messageSize := int64(32 << 10)
used := int64(0)
for used < length {
nextMessageSize, err := allocationTracking.ConsumeOrWait(messageSize)
if err != nil {
allocationTracking.Fail(err)
break
}
used += nextMessageSize
n, err := io.CopyN(writer, storeFile, nextMessageSize)
// correct errors when needed
if n != nextMessageSize {
if pErr := allocationTracking.Produce(nextMessageSize - n); pErr != nil {
break
}
used -= nextMessageSize - n
}
// break on error
if err != nil {
allocationTracking.Fail(err)
break
}
}
// write to bandwidth usage table
if err = s.DB.AddBandwidthUsed(used); err != nil {
return retrieved, allocated, StoreError.New("failed to write bandwidth info to database: %v", err)
}
// TODO: handle errors
// _ = stream.Close()
return used, atomic.LoadInt64(&totalAllocated), allocationTracking.Err()
}