feat: scheduler download tiny file with range header (#1024)

Signed-off-by: Gaius <gaius.qi@gmail.com>

scheduler/resource/peer.go

@@ -26,6 +26,7 @@ import (
 	"time"
 
 	"github.com/bits-and-blooms/bitset"
+	"github.com/go-http-utils/headers"
 	"github.com/looplab/fsm"
 	"go.uber.org/atomic"
 
@@ -402,6 +403,7 @@ func (p *Peer) DownloadTinyFile(ctx context.Context) ([]byte, error) {
 	if err != nil {
 		return []byte{}, err
 	}
+	req.Header.Set(headers.Range, fmt.Sprintf("bytes=%d-%d", 0, p.Task.ContentLength.Load()))
 
 	resp, err := http.DefaultClient.Do(req)
 	if err != nil {
@@ -409,5 +411,9 @@ func (p *Peer) DownloadTinyFile(ctx context.Context) ([]byte, error) {
 	}
 	defer resp.Body.Close()
 
+	if resp.StatusCode != http.StatusOK {
+		return []byte{}, fmt.Errorf("%v: %v", url.String(), resp.Status)
+	}
+
 	return io.ReadAll(resp.Body)
 }

scheduler/resource/peer_test.go

@@ -18,14 +18,17 @@ package resource
 
 import (
 	"context"
+	"fmt"
 	"net"
 	"net/http"
 	"net/http/httptest"
 	"net/url"
+	"path"
 	"strconv"
 	"testing"
 	"time"
 
+	"github.com/go-http-utils/headers"
 	"github.com/golang/mock/gomock"
 	"github.com/stretchr/testify/assert"
 
@@ -867,6 +870,16 @@ func TestPeer_DeleteStream(t *testing.T) {
 
 func TestPeer_DownloadTinyFile(t *testing.T) {
 	s := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if path.Base(r.URL.Path) == "foo" {
+			w.WriteHeader(http.StatusNotFound)
+			return
+		}
+
+		if r.Header.Get(headers.Range) == "bytes=0-2" {
+			w.WriteHeader(http.StatusNotAcceptable)
+			return
+		}
+
 		w.WriteHeader(http.StatusOK)
 	}))
 	defer s.Close()
@@ -886,6 +899,19 @@ func TestPeer_DownloadTinyFile(t *testing.T) {
 				assert.NoError(err)
 			},
 		},
+		{
+			name: "download tiny file with range header",
+			expect: func(t *testing.T, peer *Peer) {
+				assert := assert.New(t)
+				peer.Task.ContentLength.Store(2)
+				ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
+				defer cancel()
+
+				_, err := peer.DownloadTinyFile(ctx)
+				assert.EqualError(err, fmt.Sprintf("http://%s:%d/download/%s/%s?peerId=scheduler: 406 Not Acceptable",
+					peer.Host.IP, peer.Host.DownloadPort, peer.Task.ID[:3], peer.Task.ID))
+			},
+		},
 		{
 			name: "download tiny file failed because of port error",
 			expect: func(t *testing.T, peer *Peer) {
@@ -910,6 +936,19 @@ func TestPeer_DownloadTinyFile(t *testing.T) {
 				assert.Error(err)
 			},
 		},
+		{
+			name: "download tiny file failed because of http status code",
+			expect: func(t *testing.T, peer *Peer) {
+				assert := assert.New(t)
+				peer.Task.ID = "foo"
+				ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
+				defer cancel()
+
+				_, err := peer.DownloadTinyFile(ctx)
+				assert.EqualError(err, fmt.Sprintf("http://%s:%d/download/%s/%s?peerId=scheduler: 404 Not Found",
+					peer.Host.IP, peer.Host.DownloadPort, peer.Task.ID[:3], peer.Task.ID))
+			},
+		},
 	}
 
 	for _, tc := range tests {