OpenAPI document generation does not generate correct refs for self-referencing collection properties #58006
Description
Is there an existing issue for this?
- I have searched the existing issues
Describe the bug
Microsoft.AspNetCore.OpenApi will generate an invalid JSON schema when a parameter has a self-reference collection property. This does not seem to occur if the self reference is not a collection.
Using the following as a parameter:
public class Criteria
{
public IEnumerable<Criteria> SubCriteria { get; set; } = [ ];
}
[FromBody] Criteria criteria
Will result in the JSON schema:
"components": {
"schemas": {
"Criteria": {
"type": "object",
"properties": {
"subCriteria": {
"type": "array",
"items": {
"$ref": "#/components/schemas/#"
}
}
}
}
}
},
Which has an invalid reference:
Resolver error at components.schemas.Criteria.properties.subCriteria.items.$ref
Could not resolve reference: Could not resolve pointer: /components/schemas/ does not exist in document
This occurs with both minimal APIs and controllers.
Expected Behavior
I would expect the subCriteria items reference to correctly point at #/components/schemas/Criteria.
Steps To Reproduce
Here is a complete self-contained Program.cs which will generate the invalid OpenAPI document:
using Microsoft.AspNetCore.Mvc;
var builder = WebApplication.CreateBuilder(args);
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddOpenApi();
var app = builder.Build();
app.MapOpenApi().CacheOutput();
app.MapPost("/item/search", ([FromBody] Criteria criteria) =>
{
var items = Enumerable
.Range(1, 5)
.Select(index =>
new Item
{
Name = index.ToString(),
})
.ToArray();
return items;
})
.WithName("SearchItems")
.WithOpenApi();
app.Run();
public class Item
{
public string Name { get; set; } = default!;
}
public class Criteria
{
public IEnumerable<Criteria> SubCriteria { get; set; } = [ ];
}
And the OpenAPI document generated at /openapi/v1.json:
{
"openapi": "3.0.1",
"info": {
"title": "Sample | v1",
"version": "1.0.0"
},
"servers": [
{
"url": "http://localhost:5129"
}
],
"paths": {
"/item/search": {
"post": {
"tags": [
"Sample"
],
"operationId": "SearchItems",
"requestBody": {
"content": {
"application/json": {
"schema": {
"$ref": "#/components/schemas/Criteria"
}
}
},
"required": true
},
"responses": {
"200": {
"description": "OK",
"content": {
"application/json": {
"schema": {
"type": "array",
"items": {
"type": "object",
"properties": {
"name": {
"type": "string"
}
}
}
}
}
}
}
}
}
}
},
"components": {
"schemas": {
"Criteria": {
"type": "object",
"properties": {
"subCriteria": {
"type": "array",
"items": {
"$ref": "#/components/schemas/#"
}
}
}
}
}
},
"tags": [
{
"name": "Sample"
}
]
}
Exceptions (if any)
No response
.NET Version
9.0.100-rc.1.24452.12
Anything else?
No response