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 "io/ioutil" 24 "net/http" 25 ) 26 27 // RetriableRequest provides facilities for retrying an HTTP request. 28 type RetriableRequest struct { 29 req *http.Request 30 rc io.ReadCloser 31 br *bytes.Reader 32 } 33 34 // Prepare signals that the request is about to be sent. 35 func (rr *RetriableRequest) Prepare() (err error) { 36 // preserve the request body; this is to support retry logic as 37 // the underlying transport will always close the reqeust body 38 if rr.req.Body != nil { 39 if rr.rc != nil { 40 rr.req.Body = rr.rc 41 } else if rr.br != nil { 42 _, err = rr.br.Seek(0, io.SeekStart) 43 rr.req.Body = ioutil.NopCloser(rr.br) 44 } 45 if err != nil { 46 return err 47 } 48 if rr.req.GetBody != nil { 49 // this will allow us to preserve the body without having to 50 // make a copy. note we need to do this on each iteration 51 rr.rc, err = rr.req.GetBody() 52 if err != nil { 53 return err 54 } 55 } else if rr.br == nil { 56 // fall back to making a copy (only do this once) 57 err = rr.prepareFromByteReader() 58 } 59 } 60 return err 61 } 62 63 func removeRequestBody(req *http.Request) { 64 req.Body = nil 65 req.GetBody = nil 66 req.ContentLength = 0 67 } 68