Internalize references (#443)

openapi3/internalize_refs.go

@@ -0,0 +1,369 @@
+package openapi3
+
+import (
+	"context"
+	"path/filepath"
+	"strings"
+)
+
+type RefNameResolver func(string) string
+
+// DefaultRefResolver is a default implementation of refNameResolver for the
+// InternalizeRefs function.
+//
+// If a reference points to an element inside a document, it returns the last
+// element in the reference using filepath.Base. Otherwise if the reference points
+// to a file, it returns the file name trimmed of all extensions.
+func DefaultRefNameResolver(ref string) string {
+	if ref == "" {
+		return ""
+	}
+	split := strings.SplitN(ref, "#", 2)
+	if len(split) == 2 {
+		return filepath.Base(split[1])
+	}
+	ref = split[0]
+	for ext := filepath.Ext(ref); len(ext) > 0; ext = filepath.Ext(ref) {
+		ref = strings.TrimSuffix(ref, ext)
+	}
+	return filepath.Base(ref)
+}
+
+func schemaNames(s Schemas) []string {
+	out := make([]string, 0, len(s))
+	for i := range s {
+		out = append(out, i)
+	}
+	return out
+}
+
+func parametersMapNames(s ParametersMap) []string {
+	out := make([]string, 0, len(s))
+	for i := range s {
+		out = append(out, i)
+	}
+	return out
+}
+
+func isExternalRef(ref string) bool {
+	return ref != "" && !strings.HasPrefix(ref, "#/components/")
+}
+
+func (doc *T) addSchemaToSpec(s *SchemaRef, refNameResolver RefNameResolver) {
+	if s == nil || !isExternalRef(s.Ref) {
+		return
+	}
+
+	name := refNameResolver(s.Ref)
+	if _, ok := doc.Components.Schemas[name]; ok {
+		s.Ref = "#/components/schemas/" + name
+		return
+	}
+
+	if doc.Components.Schemas == nil {
+		doc.Components.Schemas = make(Schemas)
+	}
+	doc.Components.Schemas[name] = s.Value.NewRef()
+	s.Ref = "#/components/schemas/" + name
+}
+
+func (doc *T) addParameterToSpec(p *ParameterRef, refNameResolver RefNameResolver) {
+	if p == nil || !isExternalRef(p.Ref) {
+		return
+	}
+	name := refNameResolver(p.Ref)
+	if _, ok := doc.Components.Parameters[name]; ok {
+		p.Ref = "#/components/parameters/" + name
+		return
+	}
+
+	if doc.Components.Parameters == nil {
+		doc.Components.Parameters = make(ParametersMap)
+	}
+	doc.Components.Parameters[name] = &ParameterRef{Value: p.Value}
+	p.Ref = "#/components/parameters/" + name
+}
+
+func (doc *T) addHeaderToSpec(h *HeaderRef, refNameResolver RefNameResolver) {
+	if h == nil || !isExternalRef(h.Ref) {
+		return
+	}
+	name := refNameResolver(h.Ref)
+	if _, ok := doc.Components.Headers[name]; ok {
+		h.Ref = "#/components/headers/" + name
+		return
+	}
+	if doc.Components.Headers == nil {
+		doc.Components.Headers = make(Headers)
+	}
+	doc.Components.Headers[name] = &HeaderRef{Value: h.Value}
+	h.Ref = "#/components/headers/" + name
+}
+
+func (doc *T) addRequestBodyToSpec(r *RequestBodyRef, refNameResolver RefNameResolver) {
+	if r == nil || !isExternalRef(r.Ref) {
+		return
+	}
+	name := refNameResolver(r.Ref)
+	if _, ok := doc.Components.RequestBodies[name]; ok {
+		r.Ref = "#/components/requestBodies/" + name
+		return
+	}
+	if doc.Components.RequestBodies == nil {
+		doc.Components.RequestBodies = make(RequestBodies)
+	}
+	doc.Components.RequestBodies[name] = &RequestBodyRef{Value: r.Value}
+	r.Ref = "#/components/requestBodies/" + name
+}
+
+func (doc *T) addResponseToSpec(r *ResponseRef, refNameResolver RefNameResolver) {
+	if r == nil || !isExternalRef(r.Ref) {
+		return
+	}
+	name := refNameResolver(r.Ref)
+	if _, ok := doc.Components.Responses[name]; ok {
+		r.Ref = "#/components/responses/" + name
+		return
+	}
+	if doc.Components.Responses == nil {
+		doc.Components.Responses = make(Responses)
+	}
+	doc.Components.Responses[name] = &ResponseRef{Value: r.Value}
+	r.Ref = "#/components/responses/" + name
+
+}
+
+func (doc *T) addSecuritySchemeToSpec(ss *SecuritySchemeRef, refNameResolver RefNameResolver) {
+	if ss == nil || !isExternalRef(ss.Ref) {
+		return
+	}
+	name := refNameResolver(ss.Ref)
+	if _, ok := doc.Components.SecuritySchemes[name]; ok {
+		ss.Ref = "#/components/securitySchemes/" + name
+		return
+	}
+	if doc.Components.SecuritySchemes == nil {
+		doc.Components.SecuritySchemes = make(SecuritySchemes)
+	}
+	doc.Components.SecuritySchemes[name] = &SecuritySchemeRef{Value: ss.Value}
+	ss.Ref = "#/components/securitySchemes/" + name
+
+}
+
+func (doc *T) addExampleToSpec(e *ExampleRef, refNameResolver RefNameResolver) {
+	if e == nil || !isExternalRef(e.Ref) {
+		return
+	}
+	name := refNameResolver(e.Ref)
+	if _, ok := doc.Components.Examples[name]; ok {
+		e.Ref = "#/components/examples/" + name
+		return
+	}
+	if doc.Components.Examples == nil {
+		doc.Components.Examples = make(Examples)
+	}
+	doc.Components.Examples[name] = &ExampleRef{Value: e.Value}
+	e.Ref = "#/components/examples/" + name
+
+}
+
+func (doc *T) addLinkToSpec(l *LinkRef, refNameResolver RefNameResolver) {
+	if l == nil || !isExternalRef(l.Ref) {
+		return
+	}
+	name := refNameResolver(l.Ref)
+	if _, ok := doc.Components.Links[name]; ok {
+		l.Ref = "#/components/links/" + name
+		return
+	}
+	if doc.Components.Links == nil {
+		doc.Components.Links = make(Links)
+	}
+	doc.Components.Links[name] = &LinkRef{Value: l.Value}
+	l.Ref = "#/components/links/" + name
+
+}
+
+func (doc *T) addCallbackToSpec(c *CallbackRef, refNameResolver RefNameResolver) {
+	if c == nil || !isExternalRef(c.Ref) {
+		return
+	}
+	name := refNameResolver(c.Ref)
+	if _, ok := doc.Components.Callbacks[name]; ok {
+		c.Ref = "#/components/callbacks/" + name
+	}
+	if doc.Components.Callbacks == nil {
+		doc.Components.Callbacks = make(Callbacks)
+	}
+	doc.Components.Callbacks[name] = &CallbackRef{Value: c.Value}
+	c.Ref = "#/components/callbacks/" + name
+}
+
+func (doc *T) derefSchema(s *Schema, refNameResolver RefNameResolver) {
+	if s == nil {
+		return
+	}
+
+	for _, list := range []SchemaRefs{s.AllOf, s.AnyOf, s.OneOf} {
+		for _, s2 := range list {
+			doc.addSchemaToSpec(s2, refNameResolver)
+			if s2 != nil {
+				doc.derefSchema(s2.Value, refNameResolver)
+			}
+		}
+	}
+	for _, s2 := range s.Properties {
+		doc.addSchemaToSpec(s2, refNameResolver)
+		if s2 != nil {
+			doc.derefSchema(s2.Value, refNameResolver)
+		}
+	}
+	for _, ref := range []*SchemaRef{s.Not, s.AdditionalProperties, s.Items} {
+		doc.addSchemaToSpec(ref, refNameResolver)
+		if ref != nil {
+			doc.derefSchema(ref.Value, refNameResolver)
+		}
+	}
+}
+
+func (doc *T) derefHeaders(hs Headers, refNameResolver RefNameResolver) {
+	for _, h := range hs {
+		doc.addHeaderToSpec(h, refNameResolver)
+		doc.derefParameter(h.Value.Parameter, refNameResolver)
+	}
+}
+
+func (doc *T) derefExamples(es Examples, refNameResolver RefNameResolver) {
+	for _, e := range es {
+		doc.addExampleToSpec(e, refNameResolver)
+	}
+}
+
+func (doc *T) derefContent(c Content, refNameResolver RefNameResolver) {
+	for _, mediatype := range c {
+		doc.addSchemaToSpec(mediatype.Schema, refNameResolver)
+		if mediatype.Schema != nil {
+			doc.derefSchema(mediatype.Schema.Value, refNameResolver)
+		}
+		doc.derefExamples(mediatype.Examples, refNameResolver)
+		for _, e := range mediatype.Encoding {
+			doc.derefHeaders(e.Headers, refNameResolver)
+		}
+	}
+}
+
+func (doc *T) derefLinks(ls Links, refNameResolver RefNameResolver) {
+	for _, l := range ls {
+		doc.addLinkToSpec(l, refNameResolver)
+	}
+}
+
+func (doc *T) derefResponses(es Responses, refNameResolver RefNameResolver) {
+	for _, e := range es {
+		doc.addResponseToSpec(e, refNameResolver)
+		if e.Value != nil {
+			doc.derefHeaders(e.Value.Headers, refNameResolver)
+			doc.derefContent(e.Value.Content, refNameResolver)
+			doc.derefLinks(e.Value.Links, refNameResolver)
+		}
+	}
+}
+
+func (doc *T) derefParameter(p Parameter, refNameResolver RefNameResolver) {
+	doc.addSchemaToSpec(p.Schema, refNameResolver)
+	doc.derefContent(p.Content, refNameResolver)
+	if p.Schema != nil {
+		doc.derefSchema(p.Schema.Value, refNameResolver)
+	}
+}
+
+func (doc *T) derefRequestBody(r RequestBody, refNameResolver RefNameResolver) {
+	doc.derefContent(r.Content, refNameResolver)
+}
+
+func (doc *T) derefPaths(paths map[string]*PathItem, refNameResolver RefNameResolver) {
+	for _, ops := range paths {
+		// inline full operations
+		ops.Ref = ""
+
+		for _, op := range ops.Operations() {
+			doc.addRequestBodyToSpec(op.RequestBody, refNameResolver)
+			if op.RequestBody != nil && op.RequestBody.Value != nil {
+				doc.derefRequestBody(*op.RequestBody.Value, refNameResolver)
+			}
+			for _, cb := range op.Callbacks {
+				doc.addCallbackToSpec(cb, refNameResolver)
+				if cb.Value != nil {
+					doc.derefPaths(*cb.Value, refNameResolver)
+				}
+			}
+			doc.derefResponses(op.Responses, refNameResolver)
+			for _, param := range op.Parameters {
+				doc.addParameterToSpec(param, refNameResolver)
+				if param.Value != nil {
+					doc.derefParameter(*param.Value, refNameResolver)
+				}
+			}
+		}
+	}
+}
+
+// InternalizeRefs removes all references to external files from the spec and moves them
+// to the components section.
+//
+// refNameResolver takes in references to returns a name to store the reference under locally.
+// It MUST return a unique name for each reference type.
+// A default implementation is provided that will suffice for most use cases. See the function
+// documention for more details.
+//
+// Example:
+//
+//   doc.InternalizeRefs(context.Background(), nil)
+func (doc *T) InternalizeRefs(ctx context.Context, refNameResolver func(ref string) string) {
+	if refNameResolver == nil {
+		refNameResolver = DefaultRefNameResolver
+	}
+
+	// Handle components section
+	names := schemaNames(doc.Components.Schemas)
+	for _, name := range names {
+		schema := doc.Components.Schemas[name]
+		doc.addSchemaToSpec(schema, refNameResolver)
+		if schema != nil {
+			schema.Ref = "" // always dereference the top level
+			doc.derefSchema(schema.Value, refNameResolver)
+		}
+	}
+	names = parametersMapNames(doc.Components.Parameters)
+	for _, name := range names {
+		p := doc.Components.Parameters[name]
+		doc.addParameterToSpec(p, refNameResolver)
+		if p != nil && p.Value != nil {
+			p.Ref = "" // always dereference the top level
+			doc.derefParameter(*p.Value, refNameResolver)
+		}
+	}
+	doc.derefHeaders(doc.Components.Headers, refNameResolver)
+	for _, req := range doc.Components.RequestBodies {
+		doc.addRequestBodyToSpec(req, refNameResolver)
+		if req != nil && req.Value != nil {
+			req.Ref = "" // always dereference the top level
+			doc.derefRequestBody(*req.Value, refNameResolver)
+		}
+	}
+	doc.derefResponses(doc.Components.Responses, refNameResolver)
+	for _, ss := range doc.Components.SecuritySchemes {
+		doc.addSecuritySchemeToSpec(ss, refNameResolver)
+	}
+	doc.derefExamples(doc.Components.Examples, refNameResolver)
+	doc.derefLinks(doc.Components.Links, refNameResolver)
+	for _, cb := range doc.Components.Callbacks {
+		doc.addCallbackToSpec(cb, refNameResolver)
+		if cb != nil && cb.Value != nil {
+			cb.Ref = "" // always dereference the top level
+			doc.derefPaths(*cb.Value, refNameResolver)
+		}
+	}
+
+	doc.derefPaths(doc.Paths, refNameResolver)
+}