reflector.go/peer/http3/client.go
2021-01-14 20:38:04 +01:00

140 lines
3.6 KiB
Go

package http3
import (
"bytes"
"encoding/hex"
"fmt"
"io"
"net/http"
"sync"
"time"
"github.com/lbryio/reflector.go/internal/metrics"
"github.com/lbryio/reflector.go/shared"
"github.com/lbryio/reflector.go/store"
"github.com/lbryio/lbry.go/v2/extras/errors"
"github.com/lbryio/lbry.go/v2/stream"
"github.com/lucas-clemente/quic-go/http3"
log "github.com/sirupsen/logrus"
)
// Client is an instance of a client connected to a server.
type Client struct {
Timeout time.Duration
conn *http.Client
roundTripper *http3.RoundTripper
ServerAddr string
}
// Close closes the connection with the client.
func (c *Client) Close() error {
c.conn.CloseIdleConnections()
return c.roundTripper.Close()
}
// GetStream gets a stream
func (c *Client) GetStream(sdHash string, blobCache store.BlobStore) (stream.Stream, error) {
var sd stream.SDBlob
b, _, err := c.GetBlob(sdHash)
if err != nil {
return nil, err
}
err = sd.FromBlob(b)
if err != nil {
return nil, err
}
s := make(stream.Stream, len(sd.BlobInfos)+1-1) // +1 for sd blob, -1 for last null blob
s[0] = b
for i := 0; i < len(sd.BlobInfos)-1; i++ {
var trace shared.BlobTrace
s[i+1], trace, err = c.GetBlob(hex.EncodeToString(sd.BlobInfos[i].BlobHash))
if err != nil {
return nil, err
}
log.Debug(trace.String())
}
return s, nil
}
// HasBlob checks if the blob is available
func (c *Client) HasBlob(hash string) (bool, error) {
resp, err := c.conn.Get(fmt.Sprintf("https://%s/has/%s", c.ServerAddr, hash))
if err != nil {
return false, errors.Err(err)
}
defer resp.Body.Close()
if resp.StatusCode == http.StatusOK {
return true, nil
}
if resp.StatusCode == http.StatusNotFound {
return false, nil
}
return false, errors.Err("non 200 status code returned: %d", resp.StatusCode)
}
// GetBlob gets a blob
func (c *Client) GetBlob(hash string) (stream.Blob, shared.BlobTrace, error) {
start := time.Now()
resp, err := c.conn.Get(fmt.Sprintf("https://%s/get/%s?trace=true", c.ServerAddr, hash))
if err != nil {
return nil, shared.NewBlobTrace(time.Since(start), "http3"), errors.Err(err)
}
defer resp.Body.Close()
if resp.StatusCode == http.StatusNotFound {
fmt.Printf("%s blob not found %d\n", hash, resp.StatusCode)
return nil, shared.NewBlobTrace(time.Since(start), "http3"), errors.Err(store.ErrBlobNotFound)
} else if resp.StatusCode != http.StatusOK {
return nil, shared.NewBlobTrace(time.Since(start), "http3"), errors.Err("non 200 status code returned: %d", resp.StatusCode)
}
tmp := getBuffer()
defer putBuffer(tmp)
serialized := resp.Header.Get("Via")
trace := shared.NewBlobTrace(time.Since(start), "http3")
if serialized != "" {
parsedTrace, err := shared.Deserialize(serialized)
if err != nil {
return nil, shared.NewBlobTrace(time.Since(start), "http3"), err
}
trace = *parsedTrace
}
written, err := io.Copy(tmp, resp.Body)
if err != nil {
return nil, trace.Stack(time.Since(start), "http3"), errors.Err(err)
}
blob := make([]byte, written)
copy(blob, tmp.Bytes())
metrics.MtrInBytesUdp.Add(float64(len(blob)))
return blob, trace.Stack(time.Since(start), "http3"), nil
}
// buffer pool to reduce GC
// https://www.captaincodeman.com/2017/06/02/golang-buffer-pool-gotcha
var buffers = sync.Pool{
// New is called when a new instance is needed
New: func() interface{} {
buf := make([]byte, 0, stream.MaxBlobSize)
return bytes.NewBuffer(buf)
},
}
// getBuffer fetches a buffer from the pool
func getBuffer() *bytes.Buffer {
return buffers.Get().(*bytes.Buffer)
}
// putBuffer returns a buffer to the pool
func putBuffer(buf *bytes.Buffer) {
buf.Reset()
buffers.Put(buf)
}