1
0
Fork 0
mirror of https://codeberg.org/forgejo/forgejo.git synced 2024-12-23 12:59:11 -05:00
forgejo/vendor/github.com/go-openapi/spec/schema_loader.go
2021-02-28 18:08:33 -05:00

331 lines
8.9 KiB
Go
Vendored

// 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"
"fmt"
"log"
"net/url"
"reflect"
"strings"
"github.com/go-openapi/swag"
)
// PathLoader is a function to use when loading remote refs.
//
// This is a package level default. It may be overridden or bypassed by
// specifying the loader in ExpandOptions.
//
// NOTE: if you are using the go-openapi/loads package, it will override
// this value with its own default (a loader to retrieve YAML documents as
// well as JSON ones).
var PathLoader = func(pth string) (json.RawMessage, error) {
data, err := swag.LoadFromFileOrHTTP(pth)
if err != nil {
return nil, err
}
return json.RawMessage(data), nil
}
// resolverContext allows to share a context during spec processing.
// At the moment, it just holds the index of circular references found.
type resolverContext struct {
// circulars holds all visited circular references, to shortcircuit $ref resolution.
//
// This structure is privately instantiated and needs not be locked against
// concurrent access, unless we chose to implement a parallel spec walking.
circulars map[string]bool
basePath string
loadDoc func(string) (json.RawMessage, error)
rootID string
}
func newResolverContext(options *ExpandOptions) *resolverContext {
expandOptions := optionsOrDefault(options)
// path loader may be overridden by options
var loader func(string) (json.RawMessage, error)
if expandOptions.PathLoader == nil {
loader = PathLoader
} else {
loader = expandOptions.PathLoader
}
return &resolverContext{
circulars: make(map[string]bool),
basePath: expandOptions.RelativeBase, // keep the root base path in context
loadDoc: loader,
}
}
type schemaLoader struct {
root interface{}
options *ExpandOptions
cache ResolutionCache
context *resolverContext
}
func (r *schemaLoader) transitiveResolver(basePath string, ref Ref) *schemaLoader {
if ref.IsRoot() || ref.HasFragmentOnly {
return r
}
baseRef := MustCreateRef(basePath)
currentRef := normalizeRef(&ref, basePath)
if strings.HasPrefix(currentRef.String(), baseRef.String()) {
return r
}
// set a new root against which to resolve
rootURL := currentRef.GetURL()
rootURL.Fragment = ""
root, _ := r.cache.Get(rootURL.String())
// shallow copy of resolver options to set a new RelativeBase when
// traversing multiple documents
newOptions := r.options
newOptions.RelativeBase = rootURL.String()
return defaultSchemaLoader(root, newOptions, r.cache, r.context)
}
func (r *schemaLoader) updateBasePath(transitive *schemaLoader, basePath string) string {
if transitive != r {
if transitive.options != nil && transitive.options.RelativeBase != "" {
return normalizeBase(transitive.options.RelativeBase)
}
}
return basePath
}
func (r *schemaLoader) resolveRef(ref *Ref, target interface{}, basePath string) error {
tgt := reflect.ValueOf(target)
if tgt.Kind() != reflect.Ptr {
return ErrResolveRefNeedsAPointer
}
if ref.GetURL() == nil {
return nil
}
var (
res interface{}
data interface{}
err error
)
// Resolve against the root if it isn't nil, and if ref is pointing at the root, or has a fragment only which means
// it is pointing somewhere in the root.
root := r.root
if (ref.IsRoot() || ref.HasFragmentOnly) && root == nil && basePath != "" {
if baseRef, erb := NewRef(basePath); erb == nil {
root, _, _, _ = r.load(baseRef.GetURL())
}
}
if (ref.IsRoot() || ref.HasFragmentOnly) && root != nil {
data = root
} else {
baseRef := normalizeRef(ref, basePath)
data, _, _, err = r.load(baseRef.GetURL())
if err != nil {
return err
}
}
res = data
if ref.String() != "" {
res, _, err = ref.GetPointer().Get(data)
if err != nil {
return err
}
}
return swag.DynamicJSONToStruct(res, target)
}
func (r *schemaLoader) load(refURL *url.URL) (interface{}, url.URL, bool, error) {
debugLog("loading schema from url: %s", refURL)
toFetch := *refURL
toFetch.Fragment = ""
var err error
pth := toFetch.String()
normalized := normalizeBase(pth)
debugLog("loading doc from: %s", normalized)
data, fromCache := r.cache.Get(normalized)
if fromCache {
return data, toFetch, fromCache, nil
}
b, err := r.context.loadDoc(normalized)
if err != nil {
return nil, url.URL{}, false, err
}
var doc interface{}
if err := json.Unmarshal(b, &doc); err != nil {
return nil, url.URL{}, false, err
}
r.cache.Set(normalized, doc)
return doc, toFetch, fromCache, nil
}
// isCircular detects cycles in sequences of $ref.
//
// It relies on a private context (which needs not be locked).
func (r *schemaLoader) isCircular(ref *Ref, basePath string, parentRefs ...string) (foundCycle bool) {
normalizedRef := normalizeURI(ref.String(), basePath)
if _, ok := r.context.circulars[normalizedRef]; ok {
// circular $ref has been already detected in another explored cycle
foundCycle = true
return
}
foundCycle = swag.ContainsStrings(parentRefs, normalizedRef) // normalized windows url's are lower cased
if foundCycle {
r.context.circulars[normalizedRef] = true
}
return
}
// Resolve resolves a reference against basePath and stores the result in target.
//
// Resolve is not in charge of following references: it only resolves ref by following its URL.
//
// If the schema the ref is referring to holds nested refs, Resolve doesn't resolve them.
//
// If basePath is an empty string, ref is resolved against the root schema stored in the schemaLoader struct
func (r *schemaLoader) Resolve(ref *Ref, target interface{}, basePath string) error {
return r.resolveRef(ref, target, basePath)
}
func (r *schemaLoader) deref(input interface{}, parentRefs []string, basePath string) error {
var ref *Ref
switch refable := input.(type) {
case *Schema:
ref = &refable.Ref
case *Parameter:
ref = &refable.Ref
case *Response:
ref = &refable.Ref
case *PathItem:
ref = &refable.Ref
default:
return fmt.Errorf("unsupported type: %T: %w", input, ErrDerefUnsupportedType)
}
curRef := ref.String()
if curRef == "" {
return nil
}
normalizedRef := normalizeRef(ref, basePath)
normalizedBasePath := normalizedRef.RemoteURI()
if r.isCircular(normalizedRef, basePath, parentRefs...) {
return nil
}
if err := r.resolveRef(ref, input, basePath); r.shouldStopOnError(err) {
return err
}
if ref.String() == "" || ref.String() == curRef {
// done with rereferencing
return nil
}
parentRefs = append(parentRefs, normalizedRef.String())
return r.deref(input, parentRefs, normalizedBasePath)
}
func (r *schemaLoader) shouldStopOnError(err error) bool {
if err != nil && !r.options.ContinueOnError {
return true
}
if err != nil {
log.Println(err)
}
return false
}
func (r *schemaLoader) setSchemaID(target interface{}, id, basePath string) (string, string) {
debugLog("schema has ID: %s", id)
// handling the case when id is a folder
// remember that basePath has to point to a file
var refPath string
if strings.HasSuffix(id, "/") {
// ensure this is detected as a file, not a folder
refPath = fmt.Sprintf("%s%s", id, "placeholder.json")
} else {
refPath = id
}
// updates the current base path
// * important: ID can be a relative path
// * registers target to be fetchable from the new base proposed by this id
newBasePath := normalizeURI(refPath, basePath)
// store found IDs for possible future reuse in $ref
r.cache.Set(newBasePath, target)
// the root document has an ID: all $ref relative to that ID may
// be rebased relative to the root document
if basePath == r.context.basePath {
debugLog("root document is a schema with ID: %s (normalized as:%s)", id, newBasePath)
r.context.rootID = newBasePath
}
return newBasePath, refPath
}
func defaultSchemaLoader(
root interface{},
expandOptions *ExpandOptions,
cache ResolutionCache,
context *resolverContext) *schemaLoader {
if expandOptions == nil {
expandOptions = &ExpandOptions{}
}
cache = cacheOrDefault(cache)
if expandOptions.RelativeBase == "" {
// if no relative base is provided, assume the root document
// contains all $ref, or at least, that the relative documents
// may be resolved from the current working directory.
expandOptions.RelativeBase = baseForRoot(root, cache)
}
debugLog("effective expander options: %#v", expandOptions)
if context == nil {
context = newResolverContext(expandOptions)
}
return &schemaLoader{
root: root,
options: expandOptions,
cache: cache,
context: context,
}
}