Use vendored go-swagger (#8087)

* Use vendored go-swagger

* vendor go-swagger

* revert un wanteed change

* remove un-needed GO111MODULE

* Update Makefile

Co-Authored-By: techknowlogick <matti@mdranta.net>

vendor/github.com/go-openapi/spec/schema_loader.go

@@ -0,0 +1,275 @@
+// 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 function to use when loading remote refs
+var PathLoader func(string) (json.RawMessage, error)
+
+func init() {
+	PathLoader = func(path string) (json.RawMessage, error) {
+		data, err := swag.LoadFromFileOrHTTP(path)
+		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, which allows shortcuts.
+	// NOTE: this is not just a performance improvement: it is required to figure out
+	// circular references which participate several cycles.
+	// 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
+}
+
+func newResolverContext(originalBasePath string) *resolverContext {
+	return &resolverContext{
+		circulars: make(map[string]bool),
+		basePath:  originalBasePath, // keep the root base path in context
+	}
+}
+
+type schemaLoader struct {
+	root    interface{}
+	options *ExpandOptions
+	cache   ResolutionCache
+	context *resolverContext
+	loadDoc func(string) (json.RawMessage, error)
+}
+
+func (r *schemaLoader) transitiveResolver(basePath string, ref Ref) (*schemaLoader, error) {
+	if ref.IsRoot() || ref.HasFragmentOnly {
+		return r, nil
+	}
+
+	baseRef, _ := NewRef(basePath)
+	currentRef := normalizeFileRef(&ref, basePath)
+	if strings.HasPrefix(currentRef.String(), baseRef.String()) {
+		return r, nil
+	}
+
+	// Set a new root to resolve against
+	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()
+	debugLog("setting new root: %s", newOptions.RelativeBase)
+	resolver, err := defaultSchemaLoader(root, newOptions, r.cache, r.context)
+	if err != nil {
+		return nil, err
+	}
+
+	return resolver, nil
+}
+
+func (r *schemaLoader) updateBasePath(transitive *schemaLoader, basePath string) string {
+	if transitive != r {
+		debugLog("got a new resolver")
+		if transitive.options != nil && transitive.options.RelativeBase != "" {
+			basePath, _ = absPath(transitive.options.RelativeBase)
+			debugLog("new basePath = %s", basePath)
+		}
+	}
+	return basePath
+}
+
+func (r *schemaLoader) resolveRef(ref *Ref, target interface{}, basePath string) error {
+	tgt := reflect.ValueOf(target)
+	if tgt.Kind() != reflect.Ptr {
+		return fmt.Errorf("resolve ref: target needs to be a pointer")
+	}
+
+	refURL := ref.GetURL()
+	if refURL == nil {
+		return nil
+	}
+
+	var res interface{}
+	var data interface{}
+	var 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 := normalizeFileRef(ref, basePath)
+		debugLog("current ref is: %s", ref.String())
+		debugLog("current ref normalized file: %s", baseRef.String())
+		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 = ""
+
+	normalized := normalizeAbsPath(toFetch.String())
+
+	data, fromCache := r.cache.Get(normalized)
+	if !fromCache {
+		b, err := r.loadDoc(normalized)
+		if err != nil {
+			return nil, url.URL{}, false, err
+		}
+
+		if err := json.Unmarshal(b, &data); err != nil {
+			return nil, url.URL{}, false, err
+		}
+		r.cache.Set(normalized, data)
+	}
+
+	return data, 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 := normalizePaths(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.ContainsStringsCI(parentRefs, normalizedRef)
+	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 that ref is referring to has more refs in it. 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("deref: unsupported type %T", input)
+	}
+
+	curRef := ref.String()
+	if curRef != "" {
+		normalizedRef := normalizeFileRef(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
+		}
+
+		// NOTE(fredbi): removed basePath check => needs more testing
+		if ref.String() != "" && ref.String() != curRef {
+			parentRefs = append(parentRefs, normalizedRef.String())
+			return r.deref(input, parentRefs, normalizedBasePath)
+		}
+	}
+
+	return nil
+}
+
+func (r *schemaLoader) shouldStopOnError(err error) bool {
+	if err != nil && !r.options.ContinueOnError {
+		return true
+	}
+
+	if err != nil {
+		log.Println(err)
+	}
+
+	return false
+}
+
+func defaultSchemaLoader(
+	root interface{},
+	expandOptions *ExpandOptions,
+	cache ResolutionCache,
+	context *resolverContext) (*schemaLoader, error) {
+
+	if cache == nil {
+		cache = resCache
+	}
+	if expandOptions == nil {
+		expandOptions = &ExpandOptions{}
+	}
+	absBase, _ := absPath(expandOptions.RelativeBase)
+	if context == nil {
+		context = newResolverContext(absBase)
+	}
+	return &schemaLoader{
+		root:    root,
+		options: expandOptions,
+		cache:   cache,
+		context: context,
+		loadDoc: func(path string) (json.RawMessage, error) {
+			debugLog("fetching document at %q", path)
+			return PathLoader(path)
+		},
+	}, nil
+}