fix oneOf rendering when the oneOf field value is a proto Struct/Value

oneOf schema for a proto oneof containing an opaque field (Struct/Value)
were not being generated. This fixes it.

Signed-off-by: Shashank Ram <shashank.ram@solo.io>

changelog/v0.2.1/oneof-fix.yaml

@@ -0,0 +1,7 @@
+changelog:
+  - type: FIX
+    issueLink: https://github.com/solo-io/protoc-gen-openapi/issues/20
+    resolvesIssue: true
+    description: |
+      Fixes the rendering of oneOf schema for proto Struct/Value types
+      that are special cased to avoid recursion.

openapiGenerator.go

@@ -426,6 +426,12 @@ func (g *openapiGenerator) generateMessageSchema(message *protomodel.MessageDesc
 		fieldDesc := g.generateDescription(field)
 		fieldRules := g.validationRules(field)
 
+		// If the field is a oneof, we need to add the oneof property to the schema
+		if field.OneofIndex != nil {
+			idx := *field.OneofIndex
+			oneOfFields[idx] = append(oneOfFields[idx], fieldName)
+		}
+
 		schemaType := g.markerRegistry.GetSchemaType(fieldRules)
 		if schemaType != "" {
 			tmp := getSoloSchemaForMarkerType(schemaType)
@@ -439,12 +445,6 @@ func (g *openapiGenerator) generateMessageSchema(message *protomodel.MessageDesc
 		sr := g.fieldTypeRef(field)
 		g.markerRegistry.MustApplyRulesToSchema(fieldRules, sr.Value, markers.TargetType)
 		o.WithProperty(fieldName, sr.Value)
-
-		// If the field is a oneof, we need to add the oneof property to the schema
-		if field.OneofIndex != nil {
-			idx := *field.OneofIndex
-			oneOfFields[idx] = append(oneOfFields[idx], fieldName)
-		}
 	}
 
 	if g.protoOneof {

testdata/golden/test5/openapiv3.yaml

@@ -2,6 +2,21 @@ components:
   schemas:
     test5.Msg:
       description: This is a top-level message.
+      oneOf:
+      - not:
+          anyOf:
+          - required:
+            - oa
+          - required:
+            - ob
+          - required:
+            - oc
+      - required:
+        - oa
+      - required:
+        - ob
+      - required:
+        - oc
       properties:
         list:
           items:
@@ -25,6 +40,13 @@ components:
             rule: self.b != 'default'
         nonNested:
           type: string
+        oa:
+          type: string
+        ob:
+          x-kubernetes-preserve-unknown-fields: true
+        oc:
+          type: object
+          x-kubernetes-preserve-unknown-fields: true
         recursiveObj:
           description: Recursive object.
           items:

testdata/struct.proto

@@ -0,0 +1,95 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+syntax = "proto3";
+
+package google.protobuf;
+
+option cc_enable_arenas = true;
+option go_package = "google.golang.org/protobuf/types/known/structpb";
+option java_package = "com.google.protobuf";
+option java_outer_classname = "StructProto";
+option java_multiple_files = true;
+option objc_class_prefix = "GPB";
+option csharp_namespace = "Google.Protobuf.WellKnownTypes";
+
+// `Struct` represents a structured data value, consisting of fields
+// which map to dynamically typed values. In some languages, `Struct`
+// might be supported by a native representation. For example, in
+// scripting languages like JS a struct is represented as an
+// object. The details of that representation are described together
+// with the proto support for the language.
+//
+// The JSON representation for `Struct` is JSON object.
+message Struct {
+  // Unordered map of dynamically typed values.
+  map<string, Value> fields = 1;
+}
+
+// `Value` represents a dynamically typed value which can be either
+// null, a number, a string, a boolean, a recursive struct value, or a
+// list of values. A producer of value is expected to set one of these
+// variants. Absence of any variant indicates an error.
+//
+// The JSON representation for `Value` is JSON value.
+message Value {
+  // The kind of value.
+  oneof kind {
+    // Represents a null value.
+    NullValue null_value = 1;
+    // Represents a double value.
+    double number_value = 2;
+    // Represents a string value.
+    string string_value = 3;
+    // Represents a boolean value.
+    bool bool_value = 4;
+    // Represents a structured value.
+    Struct struct_value = 5;
+    // Represents a repeated `Value`.
+    ListValue list_value = 6;
+  }
+}
+
+// `NullValue` is a singleton enumeration to represent the null value for the
+// `Value` type union.
+//
+// The JSON representation for `NullValue` is JSON `null`.
+enum NullValue {
+  // Null value.
+  NULL_VALUE = 0;
+}
+
+// `ListValue` is a wrapper around a repeated field of values.
+//
+// The JSON representation for `ListValue` is JSON array.
+message ListValue {
+  // Repeated field of dynamically typed values.
+  repeated Value values = 1;
+}

testdata/test5/rules.proto

@@ -2,6 +2,8 @@ syntax = "proto3";
 
 package test5;
 
+import "google/protobuf/struct.proto";
+
 // This is a top-level message.
 //
 // +kubebuilder:validation:XValidation:rule="self.msgNested.a > 0",message="must be a postive value"
@@ -29,6 +31,17 @@ message Msg {
   // +kubebuilder:validation:XValidation:rule="self.x = 1"
   repeated Recursive recursive_val = 5;
 
+  // OneOf message.
+  oneof oneof_field {
+    string oa = 6;
+
+    // +kubebuilder:validation:Type=value
+    google.protobuf.Value ob = 7;
+
+    // +kubebuilder:validation:Type=object
+    google.protobuf.Struct oc = 8;
+  }
+
   // This is a nested message.
   //
   // +kubebuilder:validation:XValidation:rule="self.a > 0",message="must be a postive value"