package main
import (
+ "bytes"
+ "context"
"encoding/base64"
"encoding/hex"
"flag"
"fmt"
"io"
+ "io/ioutil"
"log"
"net/http"
"os"
"github.com/AdRoll/goamz/s3"
)
+ const (
+ s3DefaultReadTimeout = arvados.Duration(10 * time.Minute)
+ s3DefaultConnectTimeout = arvados.Duration(time.Minute)
+ )
+
var (
// ErrS3TrashDisabled is returned by Trash if that operation
// is impossible with the current config.
// Zero timeouts mean "wait forever", which is a bad
// default. Default to long timeouts instead.
if v.ConnectTimeout == 0 {
- v.ConnectTimeout = arvados.Duration(time.Minute)
+ v.ConnectTimeout = s3DefaultConnectTimeout
}
if v.ReadTimeout == 0 {
- v.ReadTimeout = arvados.Duration(10 * time.Minute)
+ v.ReadTimeout = s3DefaultReadTimeout
}
client := s3.New(auth, region)
return nil
}
+func (v *S3Volume) getReaderWithContext(ctx context.Context, loc string) (rdr io.ReadCloser, err error) {
+ ready := make(chan bool)
+ go func() {
+ rdr, err = v.getReader(loc)
+ close(ready)
+ }()
+ select {
+ case <-ready:
+ return
+ case <-ctx.Done():
+ theConfig.debugLogf("s3: abandoning getReader(): %s", ctx.Err())
+ go func() {
+ <-ready
+ if err == nil {
+ rdr.Close()
+ }
+ }()
+ return nil, ctx.Err()
+ }
+}
+
// getReader wraps (Bucket)GetReader.
//
// In situations where (Bucket)GetReader would fail because the block
// Get a block: copy the block data into buf, and return the number of
// bytes copied.
-func (v *S3Volume) Get(loc string, buf []byte) (int, error) {
- rdr, err := v.getReader(loc)
+func (v *S3Volume) Get(ctx context.Context, loc string, buf []byte) (int, error) {
+ rdr, err := v.getReaderWithContext(ctx, loc)
if err != nil {
return 0, err
}
- defer rdr.Close()
- n, err := io.ReadFull(rdr, buf)
- switch err {
- case nil, io.EOF, io.ErrUnexpectedEOF:
- return n, nil
- default:
- return 0, v.translateError(err)
+
+ var n int
+ ready := make(chan bool)
+ go func() {
+ defer close(ready)
+
+ defer rdr.Close()
+ n, err = io.ReadFull(rdr, buf)
+
+ switch err {
+ case nil, io.EOF, io.ErrUnexpectedEOF:
+ err = nil
+ default:
+ err = v.translateError(err)
+ }
+ }()
+ select {
+ case <-ctx.Done():
+ theConfig.debugLogf("s3: interrupting ReadFull() with Close() because %s", ctx.Err())
+ rdr.Close()
+ // Must wait for ReadFull to return, to ensure it
+ // doesn't write to buf after we return.
+ theConfig.debugLogf("s3: waiting for ReadFull() to fail")
+ <-ready
+ return 0, ctx.Err()
+ case <-ready:
+ return n, err
}
}
// Compare the given data with the stored data.
-func (v *S3Volume) Compare(loc string, expect []byte) error {
- rdr, err := v.getReader(loc)
+func (v *S3Volume) Compare(ctx context.Context, loc string, expect []byte) error {
+ rdr, err := v.getReaderWithContext(ctx, loc)
if err != nil {
return err
}
defer rdr.Close()
- return v.translateError(compareReaderWithBuf(rdr, expect, loc[:32]))
+ return v.translateError(compareReaderWithBuf(ctx, rdr, expect, loc[:32]))
}
// Put writes a block.
-func (v *S3Volume) Put(loc string, block []byte) error {
+func (v *S3Volume) Put(ctx context.Context, loc string, block []byte) error {
if v.ReadOnly {
return MethodDisabledError
}
var opts s3.Options
- if len(block) > 0 {
+ size := len(block)
+ if size > 0 {
md5, err := hex.DecodeString(loc)
if err != nil {
return err
}
opts.ContentMD5 = base64.StdEncoding.EncodeToString(md5)
}
- err := v.bucket.Put(loc, block, "application/octet-stream", s3ACL, opts)
- if err != nil {
+
+ // Send the block data through a pipe, so that (if we need to)
+ // we can close the pipe early and abandon our PutReader()
+ // goroutine, without worrying about PutReader() accessing our
+ // block buffer after we release it.
+ bufr, bufw := io.Pipe()
+ go func() {
+ io.Copy(bufw, bytes.NewReader(block))
+ bufw.Close()
+ }()
+
+ var err error
+ ready := make(chan bool)
+ go func() {
+ defer func() {
+ if ctx.Err() != nil {
+ theConfig.debugLogf("%s: abandoned PutReader goroutine finished with err: %s", v, err)
+ }
+ }()
+ defer close(ready)
+ err = v.bucket.PutReader(loc, bufr, int64(size), "application/octet-stream", s3ACL, opts)
+ if err != nil {
+ return
+ }
+ err = v.bucket.Put("recent/"+loc, nil, "application/octet-stream", s3ACL, s3.Options{})
+ }()
+ select {
+ case <-ctx.Done():
+ theConfig.debugLogf("%s: taking PutReader's input away: %s", v, ctx.Err())
+ // Our pipe might be stuck in Write(), waiting for
+ // io.Copy() to read. If so, un-stick it. This means
+ // PutReader will get corrupt data, but that's OK: the
+ // size and MD5 won't match, so the write will fail.
+ go io.Copy(ioutil.Discard, bufr)
+ // CloseWithError() will return once pending I/O is done.
+ bufw.CloseWithError(ctx.Err())
+ theConfig.debugLogf("%s: abandoning PutReader goroutine", v)
+ return ctx.Err()
+ case <-ready:
return v.translateError(err)
}
- err = v.bucket.Put("recent/"+loc, nil, "application/octet-stream", s3ACL, s3.Options{})
- return v.translateError(err)
}
// Touch sets the timestamp for the given locator to the current time.
projects / arvados.git / commitdiff