| // Copyright 2013 sigu-399 ( https://github.com/sigu-399 ) |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| // author sigu-399 |
| // author-github https://github.com/sigu-399 |
| // author-mail sigu.399@gmail.com |
| // |
| // repository-name gojsonreference |
| // repository-desc An implementation of JSON Reference - Go language |
| // |
| // description Main and unique file. |
| // |
| // created 26-02-2013 |
| |
| package gojsonreference |
| |
| import ( |
| "errors" |
| "github.com/sigu-399/gojsonpointer" |
| "net/url" |
| "strings" |
| ) |
| |
| const ( |
| const_fragment_char = `#` |
| ) |
| |
| func NewJsonReference(jsonReferenceString string) (JsonReference, error) { |
| |
| var r JsonReference |
| err := r.parse(jsonReferenceString) |
| return r, err |
| |
| } |
| |
| type JsonReference struct { |
| referenceUrl *url.URL |
| referencePointer gojsonpointer.JsonPointer |
| |
| HasFullUrl bool |
| HasUrlPathOnly bool |
| HasFragmentOnly bool |
| HasFileScheme bool |
| HasFullFilePath bool |
| } |
| |
| func (r *JsonReference) GetUrl() *url.URL { |
| return r.referenceUrl |
| } |
| |
| func (r *JsonReference) GetPointer() *gojsonpointer.JsonPointer { |
| return &r.referencePointer |
| } |
| |
| func (r *JsonReference) String() string { |
| |
| if r.referenceUrl != nil { |
| return r.referenceUrl.String() |
| } |
| |
| if r.HasFragmentOnly { |
| return const_fragment_char + r.referencePointer.String() |
| } |
| |
| return r.referencePointer.String() |
| } |
| |
| // "Constructor", parses the given string JSON reference |
| func (r *JsonReference) parse(jsonReferenceString string) error { |
| |
| var err error |
| |
| // fragment only |
| if strings.HasPrefix(jsonReferenceString, const_fragment_char) { |
| r.referencePointer, err = gojsonpointer.NewJsonPointer(jsonReferenceString[1:]) |
| if err != nil { |
| return nil |
| } |
| r.HasFragmentOnly = true |
| } else { |
| |
| r.referenceUrl, err = url.Parse(jsonReferenceString) |
| if err != nil { |
| return nil |
| } |
| |
| if r.referenceUrl.Scheme != "" && r.referenceUrl.Host != "" { |
| r.HasFullUrl = true |
| } else { |
| r.HasUrlPathOnly = true |
| } |
| |
| r.HasFileScheme = r.referenceUrl.Scheme == "file" |
| |
| r.HasFullFilePath = strings.HasPrefix(r.GetUrl().Path, "//") |
| |
| r.referencePointer, err = gojsonpointer.NewJsonPointer(r.referenceUrl.Fragment) |
| if err != nil { |
| return nil |
| } |
| } |
| |
| return nil |
| } |
| |
| // Creates a new reference from a parent and a child |
| // If the child cannot inherit from the parent, an error is returned |
| func (r *JsonReference) Inherits(child JsonReference) (*JsonReference, error) { |
| |
| if !r.HasFileScheme && !child.HasFileScheme { |
| return r.inheritsImplHttp(child) |
| } |
| |
| if r.HasFileScheme && child.HasFileScheme { |
| return r.inheritsImplFile(child) |
| } |
| |
| return nil, errors.New("References are not compatible") |
| |
| } |
| |
| func (r *JsonReference) inheritsImplFile(child JsonReference) (*JsonReference, error) { |
| |
| if !r.HasFullFilePath { |
| return nil, errors.New("Parent reference must be canonical") |
| } |
| |
| if !child.HasFullFilePath { |
| return nil, errors.New("Child reference must be canonical") |
| } |
| |
| inheritedReference, err := NewJsonReference(child.String()) |
| if err != nil { |
| return nil, err |
| } |
| |
| return &inheritedReference, nil |
| } |
| |
| func (r *JsonReference) inheritsImplHttp(child JsonReference) (*JsonReference, error) { |
| |
| if !r.HasFullUrl { |
| return nil, errors.New("Parent reference must be canonical") |
| } |
| |
| if r.HasFullUrl && child.HasFullUrl { |
| if r.referenceUrl.Scheme != child.referenceUrl.Scheme { |
| return nil, errors.New("References have different schemes") |
| } |
| if r.referenceUrl.Host != child.referenceUrl.Host { |
| return nil, errors.New("References have different hosts") |
| } |
| } |
| |
| inheritedReference, err := NewJsonReference(r.String()) |
| if err != nil { |
| return nil, err |
| } |
| |
| if child.HasFragmentOnly { |
| inheritedReference.referenceUrl.Fragment = child.referencePointer.String() |
| inheritedReference.referencePointer = child.referencePointer |
| } |
| if child.HasUrlPathOnly { |
| inheritedReference.referenceUrl.Path = child.referenceUrl.Path |
| } |
| if child.HasFullUrl { |
| inheritedReference.referenceUrl.Fragment = child.referenceUrl.Fragment |
| inheritedReference.referenceUrl.Path = child.referenceUrl.Path |
| } |
| return &inheritedReference, nil |
| |
| return nil, nil |
| } |