Skip to content

fix(normalizer): support OAS 3.1 annotated enums (oneOf + const) for consistent enum generation (C#) #23869

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
nagabalaji-b wants to merge 6 commits into
base: master
Choose a base branch
from
+31 −10
Open

fix(normalizer): support OAS 3.1 annotated enums (oneOf + const) for consistent enum generation (C#) #23869

Show file tree
Hide file tree
Changes from 5 commits
Commits
Show all changes
6 commits
Select commit Hold shift + click to select a range
9fbf404
Introducing Annotated Enum with const
nagabalaji-b May 22, 2026
51e0b0f
fix: support OpenAPI 3.1 const in annotated enum normalization
nagabalaji-b May 25, 2026
ba6d6a2
fix(docs): use forward slashes in path separators for cross-platform …
nagabalaji-b May 25, 2026
553b721
revert: remove unrelated doc file changes from PR scope
nagabalaji-b May 26, 2026
3496c3b
refactor(normalizer): extract definesEnum variable per reviewer sugge…
nagabalaji-b May 26, 2026
55450c4
fix(normalizer): preserve x-enum-deprecated for oneOf/anyOf const enums
nagabalaji-b Jun 5, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
15 changes: 10 additions & 5 deletions modules/openapi-generator/src/main/java/org/openapitools/codegen/OpenAPINormalizer.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1620,10 +1620,15 @@ protected Schema simplifyComposedSchemaWithEnums(Schema schema, List<Object> sub

Schema subSchema = ModelUtils.getReferencedSchema(openAPI, (Schema) item);

// Check if this sub-schema has an enum (with one or more values)
if (subSchema.getEnum() == null || subSchema.getEnum().isEmpty()) {
// Check if this sub-schema has an enum or const value (OAS 3.1 uses const for single-value enums)
boolean definesEnum = ModelUtils.hasEnum(subSchema);
if (!definesEnum && subSchema.getConst() == null) {
return schema;
}
// If const is present but enum is not, treat const as a single enum value
List<Object> subSchemaEnumValues = definesEnum
? subSchema.getEnum()
: Arrays.asList(subSchema.getConst());

// Ensure all sub-schemas have the same type (if type is specified)
if(subSchema.getTypes() != null && subSchema.getTypes().size() > 1) {
Expand All @@ -1639,17 +1644,17 @@ protected Schema simplifyComposedSchemaWithEnums(Schema schema, List<Object> sub
}
}
// Add all enum values from this sub-schema to our collection
if(subSchema.getEnum().size() == 1) {
if(subSchemaEnumValues.size() == 1) {
String description = subSchema.getTitle() == null ? "" : subSchema.getTitle();
if(subSchema.getDescription() != null) {
if(!description.isEmpty()) {
description += " - ";
}
description += subSchema.getDescription();
}
enumValues.put(subSchema.getEnum().get(0), description);
enumValues.put(subSchemaEnumValues.get(0), description);
} else {
for(Object e: subSchema.getEnum()) {
for(Object e: subSchemaEnumValues) {
enumValues.put(e, "");
}
}
Expand Down
7 changes: 4 additions & 3 deletions modules/openapi-generator/src/test/java/org/openapitools/codegen/OpenAPINormalizerTest.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1536,9 +1536,10 @@ public void testOpenAPINormalizerSimplifyOneOfAnyOf31Spec() {
assertEquals(schema14.getType(), null);

Schema schema16 = openAPI.getComponents().getSchemas().get("TypeIntegerWithOneOf");
assertEquals(schema16.getOneOf().size(),3);
assertEquals(((Schema) schema16.getOneOf().get(0)).getConst(), 1);
assertEquals(((Schema) schema16.getOneOf().get(0)).getDeprecated(), true);
// After normalization, oneOf with const values should be simplified to enum
assertEquals(schema16.getOneOf(), null);
assertEquals(schema16.getEnum().size(), 3);
assertEquals(schema16.getEnum().get(0), 1);
Copy link
Copy Markdown
Contributor

@JPPortier JPPortier May 28, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

(I'm not repo maintainer but the PR is something I was thinking about myself: so thank you)

The test against deprecated (https://github.com/nagabalaji-b/openapi-generator/blob/3496c3b7cffbc0cdc728cc77bd64708b8ba6ae9a/modules/openapi-generator/src/test/resources/3_1/simplifyOneOfAnyOf_test.yaml#L133) is lost here (and the information from schema too)

Here, seems it is not possible with current enum support implementation ("simple" list of values and optional list of descriptions with x-enum-descriptions) to support enum as "schema" enabling to keep all "schemas" related information with no loss.

Copy link
Copy Markdown
Member

@wing328 wing328 Jun 5, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

@nagabalaji-b can you please take a look and add back the deprecated test?

Copy link
Copy Markdown
Author

@nagabalaji-b nagabalaji-b Jun 5, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

@wing328 Done. I added back the deprecated test coverage:

Code change: Modified simplifyComposedSchemaWithEnums() to collect and preserve per-value deprecated flags from OAS 3.1 oneOf/anyOf + const sub-schemas into x-enum-deprecated extension.

Test assertion: Added explicit checks in testOpenAPINormalizerSimplifyOneOfAnyOf31Spec() for TypeIntegerWithOneOf schema:

Verifies x-enum-deprecated list size = 3
Verifies flags match expected values: [true, false, false] (first enum value was deprecated in the original YAML)
Validation: Ran the test locally and confirmed BUILD SUCCESS.

The deprecated metadata from the annotated enum pattern (oneOf + const) is now preserved through normalization, so generators can access it via the x-enum-deprecated extension.


Schema schema18 = openAPI.getComponents().getSchemas().get("OneOfNullAndRef3");
// original oneOf removed and simplified to just $ref (oneOf sub-schema) instead
Expand Down
Loading