1 files changed, 338 insertions, 0 deletions
diff --git a/vendor/github.com/go-openapi/spec/schema_loader.go b/vendor/github.com/go-openapi/spec/schema_loader.go
new file mode 100644
index 000000000..b81175afd
--- /dev/null
+++ b/vendor/github.com/go-openapi/spec/schema_loader.go
@@ -0,0 +1,338 @@
+// 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)
+
+	unescaped, err := url.PathUnescape(normalized)
+	if err != nil {
+		return nil, url.URL{}, false, err
+	}
+
+	u := url.URL{Path: unescaped}
+
+	data, fromCache := r.cache.Get(u.RequestURI())
+	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,
+	}
+}