Add webhooks support (#149)

Author: vearutop

openapi31/helper.go

@@ -182,6 +182,41 @@ func (s *Spec) AddOperation(method, path string, operation Operation) error {
 	})
 }
 
+// AddWebhook validates and sets webhook by name and method.
+//
+// It will fail if webhook with same name already exists.
+func (s *Spec) AddWebhook(method, name string, operation Operation) error {
+	if _, found := s.Webhooks[name]; found {
+		return fmt.Errorf("duplicate webhook name: %s", name)
+	}
+
+	method = strings.ToLower(method)
+
+	// Add "No Content" response if there are no responses configured.
+	if len(operation.ResponsesEns().MapOfResponseOrReferenceValues) == 0 && operation.Responses.Default == nil {
+		operation.Responses.WithMapOfResponseOrReferenceValuesItem(strconv.Itoa(http.StatusNoContent), ResponseOrReference{
+			Response: &Response{
+				Description: http.StatusText(http.StatusNoContent),
+			},
+		})
+	}
+
+	method, _, _, err := openapi.SanitizeMethodPath(method, "/")
+	if err != nil {
+		return err
+	}
+
+	pathItem := PathItem{}
+
+	if err := pathItem.SetOperation(method, &operation); err != nil {
+		return err
+	}
+
+	s.WithWebhooksItem(name, pathItem.PathItemOrReference())
+
+	return nil
+}
+
 // UnknownParamIsForbidden indicates forbidden unknown parameters.
 func (o Operation) UnknownParamIsForbidden(in ParameterIn) bool {
 	f, ok := o.MapOfAnything[xForbidUnknown+string(in)].(bool)
@@ -281,3 +316,10 @@ func (r *RequestBodyOrReference) SetReference(ref string) {
 	r.ReferenceEns().Ref = ref
 	r.RequestBody = nil
 }
+
+// PathItemOrReference exposes PathItem as union type.
+func (p *PathItem) PathItemOrReference() PathItemOrReference {
+	return PathItemOrReference{
+		PathItem: p,
+	}
+}

openapi31/reflect.go

@@ -28,7 +28,7 @@ func NewReflector() *Reflector {
 
 	r.DefaultOptions = append(r.DefaultOptions, jsonschema.InterceptSchema(func(params jsonschema.InterceptSchemaParams) (stop bool, err error) {
 		// See https://spec.openapis.org/oas/v3.1.0.html#data-types.
-		switch params.Value.Kind() { //nolint:exhaustive // Not all kinds have formats defined.
+		switch params.Value.Kind() { //nolint // Not all kinds have formats defined.
 		case reflect.Int64:
 			params.Schema.WithFormat("int64")
 		case reflect.Int32:
@@ -46,9 +46,9 @@ func NewReflector() *Reflector {
 }
 
 // NewOperationContext initializes openapi.OperationContext to be prepared
-// and added later with Reflector.AddOperation.
-func (r *Reflector) NewOperationContext(method, pathPattern string) (openapi.OperationContext, error) {
-	method, pathPattern, pathParams, err := openapi.SanitizeMethodPath(method, pathPattern)
+// and added later with Reflector.AddOperation or Reflector.AddWebhook.
+func (r *Reflector) NewOperationContext(method, pathPatternOrWebhookName string) (openapi.OperationContext, error) {
+	method, pathPattern, pathParams, err := openapi.SanitizeMethodPath(method, pathPatternOrWebhookName)
 	if err != nil {
 		return nil, err
 	}
@@ -61,7 +61,7 @@ func (r *Reflector) NewOperationContext(method, pathPattern string) (openapi.Ope
 	}
 
 	if operation != nil {
-		return nil, fmt.Errorf("operation already exists: %s %s", method, pathPattern)
+		return nil, fmt.Errorf("operation already exists: %s %s", method, pathPatternOrWebhookName)
 	}
 
 	operation = &Operation{}
@@ -211,24 +211,43 @@ func (o operationContext) Operation() *Operation {
 
 // AddOperation configures operation request and response schema.
 func (r *Reflector) AddOperation(oc openapi.OperationContext) error {
+	c, err := r.setupOC(oc)
+	if err != nil {
+		return err
+	}
+
+	return r.SpecEns().AddOperation(oc.Method(), oc.PathPattern(), *c.op)
+}
+
+// AddWebhook configures webhook request and response schema.
+func (r *Reflector) AddWebhook(oc openapi.OperationContext) error {
+	c, err := r.setupOC(oc)
+	if err != nil {
+		return err
+	}
+
+	return r.SpecEns().AddWebhook(oc.Method(), c.PathPattern(), *c.op)
+}
+
+func (r *Reflector) setupOC(oc openapi.OperationContext) (operationContext, error) {
 	c, ok := oc.(operationContext)
 	if !ok {
-		return fmt.Errorf("wrong operation context %T received, %T expected", oc, operationContext{})
+		return c, fmt.Errorf("wrong operation context %T received, %T expected", oc, operationContext{})
 	}
 
 	if err := r.setupRequest(c.op, oc); err != nil {
-		return fmt.Errorf("setup request %s %s: %w", oc.Method(), oc.PathPattern(), err)
+		return c, fmt.Errorf("setup request %s %s: %w", oc.Method(), oc.PathPattern(), err)
 	}
 
 	if err := c.op.validatePathParams(c.pathParams); err != nil {
-		return fmt.Errorf("validate path params %s %s: %w", oc.Method(), oc.PathPattern(), err)
+		return c, fmt.Errorf("validate path params %s %s: %w", oc.Method(), oc.PathPattern(), err)
 	}
 
 	if err := r.setupResponse(c.op, oc); err != nil {
-		return fmt.Errorf("setup response %s %s: %w", oc.Method(), oc.PathPattern(), err)
+		return c, fmt.Errorf("setup response %s %s: %w", oc.Method(), oc.PathPattern(), err)
 	}
 
-	return r.SpecEns().AddOperation(oc.Method(), oc.PathPattern(), *c.op)
+	return c, nil
 }
 
 func (r *Reflector) setupRequest(o *Operation, oc openapi.OperationContext) error {

openapi31/reflect_test.go

@@ -1594,3 +1594,55 @@ func TestSelfReference(t *testing.T) {
 	  }
 	}`, reflector.SpecSchema())
 }
+
+func TestReflector_AddWebhook(t *testing.T) {
+	r := openapi31.NewReflector()
+
+	oc, err := r.NewOperationContext(http.MethodPost, "newPet")
+	require.NoError(t, err)
+
+	type Pet struct {
+		Name  string `json:"name"`
+		Breed string `json:"breed"`
+	}
+
+	oc.AddReqStructure(Pet{}, func(cu *openapi.ContentUnit) {
+		cu.Description = "Information about a new pet in the system"
+	})
+
+	oc.AddRespStructure(nil, func(cu *openapi.ContentUnit) {
+		cu.Description = "Return a 200 status to indicate that the data was received successfully"
+		cu.HTTPStatus = http.StatusOK
+	})
+
+	require.NoError(t, r.AddWebhook(oc))
+
+	assertjson.EqMarshal(t, `{
+	  "openapi":"3.1.0","info":{"title":"","version":""},"paths":{},
+	  "webhooks":{
+		"newPet":{
+		  "post":{
+			"requestBody":{
+			  "description":"Information about a new pet in the system",
+			  "content":{
+				"application/json":{"schema":{"$ref":"#/components/schemas/Openapi31TestPet"}}
+			  }
+			},
+			"responses":{
+			  "200":{
+				"description":"Return a 200 status to indicate that the data was received successfully"
+			  }
+			}
+		  }
+		}
+	  },
+	  "components":{
+		"schemas":{
+		  "Openapi31TestPet":{
+			"properties":{"breed":{"type":"string"},"name":{"type":"string"}},
+			"type":"object"
+		  }
+		}
+	  }
+	}`, r.SpecEns())
+}