1 //go:build go1.8
2 // +build go1.8
3 4 // Copyright 2017 Microsoft Corporation
5 //
6 // Licensed under the Apache License, Version 2.0 (the "License");
7 // you may not use this file except in compliance with the License.
8 // You may obtain a copy of the License at
9 //
10 // http://www.apache.org/licenses/LICENSE-2.0
11 //
12 // Unless required by applicable law or agreed to in writing, software
13 // distributed under the License is distributed on an "AS IS" BASIS,
14 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 // See the License for the specific language governing permissions and
16 // limitations under the License.
17 18 package autorest
19 20 import (
21 "bytes"
22 "io"
23 "net/http"
24 )
25 26 // RetriableRequest provides facilities for retrying an HTTP request.
27 type RetriableRequest struct {
28 req *http.Request
29 rc io.ReadCloser
30 br *bytes.Reader
31 }
32 33 // Prepare signals that the request is about to be sent.
34 func (rr *RetriableRequest) Prepare() (err error) {
35 // preserve the request body; this is to support retry logic as
36 // the underlying transport will always close the reqeust body
37 if rr.req.Body != nil && rr.req.Body != http.NoBody {
38 if rr.rc != nil {
39 rr.req.Body = rr.rc
40 } else if rr.br != nil {
41 _, err = rr.br.Seek(0, io.SeekStart)
42 rr.req.Body = io.NopCloser(rr.br)
43 }
44 if err != nil {
45 return err
46 }
47 if rr.req.GetBody != nil {
48 // this will allow us to preserve the body without having to
49 // make a copy. note we need to do this on each iteration
50 rr.rc, err = rr.req.GetBody()
51 if err != nil {
52 return err
53 }
54 } else if rr.br == nil {
55 // fall back to making a copy (only do this once)
56 err = rr.prepareFromByteReader()
57 }
58 }
59 return err
60 }
61 62 func removeRequestBody(req *http.Request) {
63 req.Body = nil
64 req.GetBody = nil
65 req.ContentLength = 0
66 }
67