chore(filer): zero copy upload file

Author: duanhongyi

volumes/filer.go

@@ -2,12 +2,14 @@
 package volumes
 
 import (
+	"bytes"
 	"encoding/json"
 	"fmt"
 	"io"
 	"mime/multipart"
 	"net/http"
 	"net/url"
+	"strings"
 
 	drycc "github.com/drycc/controller-sdk-go"
 	"github.com/drycc/controller-sdk-go/api"
@@ -42,32 +44,29 @@ func GetFile(c *drycc.Client, appID, volumeID, path string) (*http.Response, err
 }
 
 // Put file to an app's volume.
-func PostFile(c *drycc.Client, appID, volumeID, volumePath, name string, reader io.Reader) (*http.Response, error) {
-	pr, pw := io.Pipe()
-	writer := multipart.NewWriter(pw)
-	go func() {
-		if err := writer.WriteField("path", volumePath); err != nil {
-			pw.CloseWithError(err)
-			return
-		}
-		part, err := writer.CreateFormFile("file", name)
-		if err != nil {
-			pw.CloseWithError(err)
-			return
-		}
-		_, err = io.Copy(part, reader)
-		if err != nil {
-			pw.CloseWithError(err)
-			return
-		}
-		pw.CloseWithError(writer.Close())
-	}()
+func PostFile(c *drycc.Client, appID, volumeID, volumePath, name string, size int64, reader io.Reader) (*http.Response, error) {
 
+	buffer := new(bytes.Buffer)
+	writer := multipart.NewWriter(buffer)
+	if err := writer.WriteField("path", volumePath); err != nil {
+		return nil, err
+	}
+	if _, err := writer.CreateFormFile("file", name); err != nil {
+		return nil, err
+	}
+	size += int64(buffer.Len())
+	head := strings.NewReader(buffer.String())
+	buffer.Reset()
+	writer.Close()
+	bottom := strings.NewReader(buffer.String())
+	size += int64(buffer.Len())
 	u := fmt.Sprintf("/v2/apps/%s/volumes/%s/client/", appID, volumeID)
-	r, err := c.NewRequest("POST", u, pr)
+
+	r, err := c.NewRequest("POST", u, io.MultiReader(head, reader, bottom))
 	if err != nil {
 		return nil, err
 	}
+	r.ContentLength = size
 	r.Header.Add("Content-Type", writer.FormDataContentType())
 	return c.Do(r)
 }

volumes/filer_test.go

@@ -147,7 +147,12 @@ func TestVolumesPostFile(t *testing.T) {
 	}
 	defer file.Close()
 
-	if _, err := PostFile(drycc, "example-go", "myvolume", "tmp/", file.Name(), file); err != nil {
+	fileinfo, err := file.Stat()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if _, err := PostFile(drycc, "example-go", "myvolume", "tmp/", file.Name(), fileinfo.Size(), file); err != nil {
 		t.Fatal(err)
 	}