Add read-only support to protoc-gen-swagger output (#882)

Can be set via:
* explicit swagger option on the field
* Implicit comment "Output only." on the field

Author: hypnoce

protoc-gen-swagger/genswagger/template.go

@@ -275,6 +275,7 @@ func renderMessagesAsDefinition(messages messageMap, d swaggerDefinitionsObject,
 
 			// Warning: Make sure not to overwrite any fields already set on the schema type.
 			schema.ExternalDocs = protoSchema.ExternalDocs
+			schema.ReadOnly = protoSchema.ReadOnly
 			schema.MultipleOf = protoSchema.MultipleOf
 			schema.Maximum = protoSchema.Maximum
 			schema.ExclusiveMaximum = protoSchema.ExclusiveMaximum
@@ -1223,6 +1224,12 @@ func updateSwaggerDataFromComments(swaggerObject interface{}, comment string, is
 	// Figure out which properties to update.
 	summaryValue := infoObjectValue.FieldByName("Summary")
 	descriptionValue := infoObjectValue.FieldByName("Description")
+	readOnlyValue := infoObjectValue.FieldByName("ReadOnly")
+
+	if readOnlyValue.Kind() == reflect.Bool && readOnlyValue.CanSet() && strings.Contains(comment, "Output only.") {
+		readOnlyValue.Set(reflect.ValueOf(true))
+	}
+
 	usingTitle := false
 	if !summaryValue.CanSet() {
 		summaryValue = infoObjectValue.FieldByName("Title")
@@ -1539,6 +1546,7 @@ func protoJSONSchemaToSwaggerSchemaCore(j *swagger_options.JSONSchema, reg *desc
 func updateSwaggerObjectFromJSONSchema(s *swaggerSchemaObject, j *swagger_options.JSONSchema) {
 	s.Title = j.GetTitle()
 	s.Description = j.GetDescription()
+	s.ReadOnly = j.GetReadOnly()
 	s.MultipleOf = j.GetMultipleOf()
 	s.Maximum = j.GetMaximum()
 	s.ExclusiveMaximum = j.GetExclusiveMaximum()

protoc-gen-swagger/genswagger/template_test.go

@@ -2,6 +2,7 @@ package genswagger
 
 import (
 	"encoding/json"
+	"errors"
 	"fmt"
 	"reflect"
 	"testing"
@@ -1274,6 +1275,7 @@ func TestRenderMessagesAsDefinition(t *testing.T) {
 						MaxProperties:    33,
 						MinProperties:    22,
 						Required:         []string{"req"},
+						ReadOnly:         true,
 					},
 				},
 			},
@@ -1298,6 +1300,7 @@ func TestRenderMessagesAsDefinition(t *testing.T) {
 					MaxProperties:    33,
 					MinProperties:    22,
 					Required:         []string{"req"},
+					ReadOnly:         true,
 				},
 			},
 		},
@@ -1498,3 +1501,135 @@ func TestProtoComments(t *testing.T) {
 		}
 	}
 }
+
+func TestUpdateSwaggerDataFromComments(t *testing.T) {
+
+	tests := []struct {
+		descr                   string
+		swaggerObject           interface{}
+		comments                string
+		expectedError           error
+		expectedSwaggerObject   interface{}
+	}{
+		{
+			descr: "empty comments",
+			swaggerObject: nil,
+			expectedSwaggerObject: nil,
+			comments: "",
+			expectedError: nil,
+		},
+		{
+			descr: "set field to read only",
+			swaggerObject: &swaggerSchemaObject{},
+			expectedSwaggerObject: &swaggerSchemaObject{
+				ReadOnly: true,
+				Description: "... Output only. ...",
+			},
+			comments: "... Output only. ...",
+			expectedError: nil,
+		},
+		{
+			descr: "set title",
+			swaggerObject: &swaggerSchemaObject{},
+			expectedSwaggerObject: &swaggerSchemaObject{
+				Title: "Comment with no trailing dot",
+			},
+			comments: "Comment with no trailing dot",
+			expectedError: nil,
+		},
+		{
+			descr: "set description",
+			swaggerObject: &swaggerSchemaObject{},
+			expectedSwaggerObject: &swaggerSchemaObject{
+				Description: "Comment with trailing dot.",
+			},
+			comments: "Comment with trailing dot.",
+			expectedError: nil,
+		},
+		{
+			descr: "use info object",
+			swaggerObject: &swaggerObject{
+				Info: swaggerInfoObject{
+				},
+			},
+			expectedSwaggerObject: &swaggerObject{
+				Info: swaggerInfoObject{
+					Description: "Comment with trailing dot.",
+				},
+			},
+			comments: "Comment with trailing dot.",
+			expectedError: nil,
+		},
+		{
+			descr: "multi line comment with title",
+			swaggerObject: &swaggerSchemaObject{},
+			expectedSwaggerObject: &swaggerSchemaObject {
+				Title: "First line",
+				Description: "Second line",
+			},
+			comments: "First line\n\nSecond line",
+			expectedError: nil,
+		},
+		{
+			descr: "multi line comment no title",
+			swaggerObject: &swaggerSchemaObject{},
+			expectedSwaggerObject: &swaggerSchemaObject {
+				Description: "First line.\n\nSecond line",
+			},
+			comments: "First line.\n\nSecond line",
+			expectedError: nil,
+		},
+		{
+			descr: "multi line comment with summary with dot",
+			swaggerObject: &swaggerOperationObject{},
+			expectedSwaggerObject: &swaggerOperationObject {
+				Summary: "First line.",
+				Description: "Second line",
+			},
+			comments: "First line.\n\nSecond line",
+			expectedError: nil,
+		},
+		{
+			descr: "multi line comment with summary no dot",
+			swaggerObject: &swaggerOperationObject{},
+			expectedSwaggerObject: &swaggerOperationObject {
+				Summary: "First line",
+				Description: "Second line",
+			},
+			comments: "First line\n\nSecond line",
+			expectedError: nil,
+		},
+		{
+			descr: "multi line comment with summary no dot",
+			swaggerObject: &schemaCore{},
+			expectedSwaggerObject: &schemaCore{},
+			comments: "Any comment",
+			expectedError: errors.New("no description nor summary property"),
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.descr, func(t *testing.T) {
+			err := updateSwaggerDataFromComments(test.swaggerObject, test.comments, false)
+
+			if test.expectedError == nil {
+				if err != nil {
+					t.Errorf("unexpected error '%v'", err)
+				}
+				if !reflect.DeepEqual(test.swaggerObject, test.expectedSwaggerObject) {
+					t.Errorf("swaggerObject was not updated corretly, expected '%+v', got '%+v'", test.expectedSwaggerObject, test.swaggerObject)
+				}
+			} else {
+				if err == nil {
+					t.Error("expected update error not returned")
+				}
+				if !reflect.DeepEqual(test.swaggerObject, test.expectedSwaggerObject) {
+					t.Errorf("swaggerObject was not updated corretly, expected '%+v', got '%+v'", test.expectedSwaggerObject, test.swaggerObject)
+				}
+				if err.Error() != test.expectedError.Error() {
+					t.Errorf("expected error malformed, expected %q, got %q", test.expectedError.Error(), err.Error())
+				}
+			}
+		})
+	}
+}

protoc-gen-swagger/genswagger/types.go

@@ -209,6 +209,7 @@ type swaggerSchemaObject struct {
 
 	ExternalDocs *swaggerExternalDocumentationObject `json:"externalDocs,omitempty"`
 
+	ReadOnly         bool     `json:"readOnly,omitempty"`
 	MultipleOf       float64  `json:"multipleOf,omitempty"`
 	Maximum          float64  `json:"maximum,omitempty"`
 	ExclusiveMaximum bool     `json:"exclusiveMaximum,omitempty"`