1// Copyright 2015 xeipuuv ( https://github.com/xeipuuv ) 2// 3// Licensed under the Apache License, Version 2.0 (the "License"); 4// you may not use this file except in compliance with the License. 5// You may obtain a copy of the License at 6// 7// http://www.apache.org/licenses/LICENSE-2.0 8// 9// Unless required by applicable law or agreed to in writing, software 10// distributed under the License is distributed on an "AS IS" BASIS, 11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12// See the License for the specific language governing permissions and 13// limitations under the License. 14 15// author xeipuuv 16// author-github https://github.com/xeipuuv 17// author-mail xeipuuv@gmail.com 18// 19// repository-name gojsonreference 20// repository-desc An implementation of JSON Reference - Go language 21// 22// description Main and unique file. 23// 24// created 26-02-2013 25 26package gojsonreference 27 28import ( 29 "errors" 30 "net/url" 31 "path/filepath" 32 "runtime" 33 "strings" 34 35 "github.com/xeipuuv/gojsonpointer" 36) 37 38const ( 39 const_fragment_char = `#` 40) 41 42func NewJsonReference(jsonReferenceString string) (JsonReference, error) { 43 44 var r JsonReference 45 err := r.parse(jsonReferenceString) 46 return r, err 47 48} 49 50type JsonReference struct { 51 referenceUrl *url.URL 52 referencePointer gojsonpointer.JsonPointer 53 54 HasFullUrl bool 55 HasUrlPathOnly bool 56 HasFragmentOnly bool 57 HasFileScheme bool 58 HasFullFilePath bool 59} 60 61func (r *JsonReference) GetUrl() *url.URL { 62 return r.referenceUrl 63} 64 65func (r *JsonReference) GetPointer() *gojsonpointer.JsonPointer { 66 return &r.referencePointer 67} 68 69func (r *JsonReference) String() string { 70 71 if r.referenceUrl != nil { 72 return r.referenceUrl.String() 73 } 74 75 if r.HasFragmentOnly { 76 return const_fragment_char + r.referencePointer.String() 77 } 78 79 return r.referencePointer.String() 80} 81 82func (r *JsonReference) IsCanonical() bool { 83 return (r.HasFileScheme && r.HasFullFilePath) || (!r.HasFileScheme && r.HasFullUrl) 84} 85 86// "Constructor", parses the given string JSON reference 87func (r *JsonReference) parse(jsonReferenceString string) (err error) { 88 89 r.referenceUrl, err = url.Parse(jsonReferenceString) 90 if err != nil { 91 return 92 } 93 refUrl := r.referenceUrl 94 95 if refUrl.Scheme != "" && refUrl.Host != "" { 96 r.HasFullUrl = true 97 } else { 98 if refUrl.Path != "" { 99 r.HasUrlPathOnly = true 100 } else if refUrl.RawQuery == "" && refUrl.Fragment != "" { 101 r.HasFragmentOnly = true 102 } 103 } 104 105 r.HasFileScheme = refUrl.Scheme == "file" 106 if runtime.GOOS == "windows" { 107 // on Windows, a file URL may have an extra leading slash, and if it 108 // doesn't then its first component will be treated as the host by the 109 // Go runtime 110 if refUrl.Host == "" && strings.HasPrefix(refUrl.Path, "/") { 111 r.HasFullFilePath = filepath.IsAbs(refUrl.Path[1:]) 112 } else { 113 r.HasFullFilePath = filepath.IsAbs(refUrl.Host + refUrl.Path) 114 } 115 } else { 116 r.HasFullFilePath = filepath.IsAbs(refUrl.Path) 117 } 118 119 // invalid json-pointer error means url has no json-pointer fragment. simply ignore error 120 r.referencePointer, _ = gojsonpointer.NewJsonPointer(refUrl.Fragment) 121 122 return 123} 124 125// Creates a new reference from a parent and a child 126// If the child cannot inherit from the parent, an error is returned 127func (r *JsonReference) Inherits(child JsonReference) (*JsonReference, error) { 128 if child.GetUrl() == nil { 129 return nil, errors.New("childUrl is nil!") 130 } 131 132 if r.GetUrl() == nil { 133 return nil, errors.New("parentUrl is nil!") 134 } 135 136 // Get a copy of the parent url to make sure we do not modify the original. 137 // URL reference resolving fails if the fragment of the child is empty, but the parent's is not. 138 // The fragment of the child must be used, so the fragment of the parent is manually removed. 139 parentUrl := *r.GetUrl() 140 parentUrl.Fragment = "" 141 142 ref, err := NewJsonReference(parentUrl.ResolveReference(child.GetUrl()).String()) 143 if err != nil { 144 return nil, err 145 } 146 return &ref, err 147} 148