1 package autorest 2 3 // Copyright 2017 Microsoft Corporation 4 // 5 // Licensed under the Apache License, Version 2.0 (the "License"); 6 // you may not use this file except in compliance with the License. 7 // You may obtain a copy of the License at 8 // 9 // http://www.apache.org/licenses/LICENSE-2.0 10 // 11 // Unless required by applicable law or agreed to in writing, software 12 // distributed under the License is distributed on an "AS IS" BASIS, 13 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 // See the License for the specific language governing permissions and 15 // limitations under the License. 16 17 import ( 18 "fmt" 19 "net/http" 20 "strings" 21 ) 22 23 // SASTokenAuthorizer implements an authorization for SAS Token Authentication 24 // this can be used for interaction with Blob Storage Endpoints 25 type SASTokenAuthorizer struct { 26 sasToken string 27 } 28 29 // NewSASTokenAuthorizer creates a SASTokenAuthorizer using the given credentials 30 func NewSASTokenAuthorizer(sasToken string) (*SASTokenAuthorizer, error) { 31 if strings.TrimSpace(sasToken) == "" { 32 return nil, fmt.Errorf("sasToken cannot be empty") 33 } 34 35 token := sasToken 36 if strings.HasPrefix(sasToken, "?") { 37 token = strings.TrimPrefix(sasToken, "?") 38 } 39 40 return &SASTokenAuthorizer{ 41 sasToken: token, 42 }, nil 43 } 44 45 // WithAuthorization returns a PrepareDecorator that adds a shared access signature token to the 46 // URI's query parameters. This can be used for the Blob, Queue, and File Services. 47 // 48 // See https://docs.microsoft.com/en-us/rest/api/storageservices/delegate-access-with-shared-access-signature 49 func (sas *SASTokenAuthorizer) WithAuthorization() PrepareDecorator { 50 return func(p Preparer) Preparer { 51 return PreparerFunc(func(r *http.Request) (*http.Request, error) { 52 r, err := p.Prepare(r) 53 if err != nil { 54 return r, err 55 } 56 57 if r.URL.RawQuery == "" { 58 r.URL.RawQuery = sas.sasToken 59 } else if !strings.Contains(r.URL.RawQuery, sas.sasToken) { 60 r.URL.RawQuery = fmt.Sprintf("%s&%s", r.URL.RawQuery, sas.sasToken) 61 } 62 63 return Prepare(r) 64 }) 65 } 66 } 67