Issue 1578 reproduction (strict server additionalProps marshal failure)

internal/test/issues/issue-1578/config.yaml

@@ -0,0 +1,6 @@
+package: issue1578
+generate:
+ models: true
+ echo-server: true
+ strict-server: true
+output: issue1578.gen.go

internal/test/issues/issue-1578/doc.go

@@ -0,0 +1,3 @@
+package issue1578
+
+//go:generate go run github.com/deepmap/oapi-codegen/v2/cmd/oapi-codegen --config=config.yaml issue1578.yaml

internal/test/issues/issue-1578/issue1578.yaml

@@ -0,0 +1,20 @@
+openapi: "3.0.1"
+components:
+ schemas:
+ ComplexObject:
+ type: object
+ properties:
+ field1:
+ type: string
+ additionalProperties: {}
+paths:
+ /test:
+ get:
+ operationId: test
+ responses:
+ 200:
+ description: test
+ content:
+ application/json:
+ schema:
+ $ref: "#/components/schemas/ComplexObject"

internal/test/issues/issue-1578/issue1578_test.go

@@ -0,0 +1,36 @@
+package issue1578_test
+
+import (
+ "bytes"
+ "context"
+ issue1578 "github.com/deepmap/oapi-codegen/v2/internal/test/issues/issue-1578"
+ "github.com/stretchr/testify/assert"
+ "github.com/stretchr/testify/require"
+ "io"
+ "net/http/httptest"
+ "testing"
+)
+
+var _ issue1578.StrictServerInterface = &testStrictServerInterface{}
+
+type testStrictServerInterface struct {
+}
+
+func (t testStrictServerInterface) Test(_ context.Context, _ issue1578.TestRequestObject) (issue1578.TestResponseObject, error) {
+ return issue1578.Test200JSONResponse(issue1578.ComplexObject{
+ AdditionalProperties: map[string]interface{}{
+ "message": "hello",
+ },
+ }), nil
+}
+
+func TestIssue1578(t *testing.T) {
+ responseObject, _ := testStrictServerInterface{}.Test(context.Background(), issue1578.TestRequestObject{})
+ response := &httptest.ResponseRecorder{
+ Body: new(bytes.Buffer),
+ }
+ err := responseObject.VisitTestResponse(response)
+ require.NoError(t, err)
+ data, _ := io.ReadAll(response.Body)
+ assert.JSONEq(t, `{"message":"hello"}`, string(data))
+}

internal/test/issues/issue-1578/ugly_workaround.go

@@ -0,0 +1,8 @@
+package issue1578
+
+// This is an ugly workaround for the issue
+//var _ json.Marshaler = Test200JSONResponse{}
+//
+//func (response Test200JSONResponse) MarshalJSON() ([]byte, error) {
+// return json.Marshal(ComplexObject(response))
+//}