prometheus/vendor/github.com/go-openapi/spec/ref.go

168 lines
3.5 KiB
Go

// Copyright 2015 go-swagger maintainers
//
// 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.
package spec
import (
"encoding/json"
"net/http"
"os"
"path/filepath"
"github.com/go-openapi/jsonreference"
)
// Refable is a struct for things that accept a $ref property
type Refable struct {
Ref Ref
}
// MarshalJSON marshals the ref to json
func (r Refable) MarshalJSON() ([]byte, error) {
return r.Ref.MarshalJSON()
}
// UnmarshalJSON unmarshalss the ref from json
func (r *Refable) UnmarshalJSON(d []byte) error {
return json.Unmarshal(d, &r.Ref)
}
// Ref represents a json reference that is potentially resolved
type Ref struct {
jsonreference.Ref
}
// RemoteURI gets the remote uri part of the ref
func (r *Ref) RemoteURI() string {
if r.String() == "" {
return r.String()
}
u := *r.GetURL()
u.Fragment = ""
return u.String()
}
// IsValidURI returns true when the url the ref points to can be found
func (r *Ref) IsValidURI() bool {
if r.String() == "" {
return true
}
v := r.RemoteURI()
if v == "" {
return true
}
if r.HasFullURL {
rr, err := http.Get(v)
if err != nil {
return false
}
return rr.StatusCode/100 == 2
}
if !(r.HasFileScheme || r.HasFullFilePath || r.HasURLPathOnly) {
return false
}
// check for local file
pth := v
if r.HasURLPathOnly {
p, e := filepath.Abs(pth)
if e != nil {
return false
}
pth = p
}
fi, err := os.Stat(pth)
if err != nil {
return false
}
return !fi.IsDir()
}
// Inherits creates a new reference from a parent and a child
// If the child cannot inherit from the parent, an error is returned
func (r *Ref) Inherits(child Ref) (*Ref, error) {
ref, err := r.Ref.Inherits(child.Ref)
if err != nil {
return nil, err
}
return &Ref{Ref: *ref}, nil
}
// NewRef creates a new instance of a ref object
// returns an error when the reference uri is an invalid uri
func NewRef(refURI string) (Ref, error) {
ref, err := jsonreference.New(refURI)
if err != nil {
return Ref{}, err
}
return Ref{Ref: ref}, nil
}
// MustCreateRef creates a ref object but
func MustCreateRef(refURI string) Ref {
return Ref{Ref: jsonreference.MustCreateRef(refURI)}
}
// // NewResolvedRef creates a resolved ref
// func NewResolvedRef(refURI string, data interface{}) Ref {
// return Ref{
// Ref: jsonreference.MustCreateRef(refURI),
// Resolved: data,
// }
// }
// MarshalJSON marshals this ref into a JSON object
func (r Ref) MarshalJSON() ([]byte, error) {
str := r.String()
if str == "" {
if r.IsRoot() {
return []byte(`{"$ref":"#"}`), nil
}
return []byte("{}"), nil
}
v := map[string]interface{}{"$ref": str}
return json.Marshal(v)
}
// UnmarshalJSON unmarshals this ref from a JSON object
func (r *Ref) UnmarshalJSON(d []byte) error {
var v map[string]interface{}
if err := json.Unmarshal(d, &v); err != nil {
return err
}
if v == nil {
return nil
}
if vv, ok := v["$ref"]; ok {
if str, ok := vv.(string); ok {
ref, err := jsonreference.New(str)
if err != nil {
return err
}
*r = Ref{Ref: ref}
}
}
return nil
}