NullReferenceException when generating code for a parameter with no schema

[Numpsy]

Hi,

I tried pointing the provider at an OpenApi schema on a new project at work, and got a NullReferenceException from it, causing the build to fail.

Trying to minimise the issue, it looks like if I have something like

{
  "openapi": "3.1.1",
  "info": {
    "title": "Testing | v1",
    "version": "0.2.0.0"
  },
  "paths": {
    "/api/v1/catalogues/scan": {
      "post": {
        "tags": [
          "Catalogue"
        ],
        "summary": "Testing",
        "description": "Testing",
        "operationId": "Scan",
        "parameters": [
          {
            "name": "properties",
            "in": "header",
            "description": "header description",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "stage-location": {
                      "type": "string",
                      "description": "location"
                    },
                    "file-size": {
                      "minimum": 0,
                      "type": "integer",
                      "format": "int64"
                    }
                  }
                }
              }
            }
          }
        ],
        "responses": {
          "200": {
            "description": "OK",
            "content": {
              "text/plain": {
                "schema": {
                  "type": "string"
                }
              }
            }
          }
        }
      }
    }
  }
}

The the provider gets to

SwaggerProvider/src/SwaggerProvider.DesignTime/DefinitionCompiler.fs

Line 440 in 4e299fd

if schemaObj.Type.HasValue then

and then throws because schemaObj is null.

Looking higher up the callstack around

SwaggerProvider/src/SwaggerProvider.DesignTime/OperationCompiler.fs

Line 206 in 4e299fd

let paramType =

, current.Schema is null, but it does have a 'Content' property, and that does contain a schema.

This is as far as I've got looking at it so far, will have another look next week if no one else of repo assist gets to it first.

Thanks.

[github-actions]

🤖 This is an automated response from Repo Assist.

Thanks for the excellent, well-isolated repro — it made this quick to track down!

Confirmed root cause: your properties header parameter uses content (a media-type map) instead of schema to describe its type, which is valid per the OpenAPI spec. The compiler only ever read IOpenApiParameter.Schema, which is null in that case, and the null was passed straight into the definition compiler, causing the NullReferenceException you traced.

I've opened a draft PR with a fix: it falls back to the schema of the content entry when Schema is absent, with a regression test using your exact schema. Build passes and all unit tests (575/575) pass.

I'll leave the PR link visible in this repo's PR list for a maintainer to review — it should resolve this issue once merged.

Generated by 🌈 Repo Assist, see workflow run. Learn more.
_{Comment /repo-assist to run again}

_{Add this agentic workflow to your repo}

To install this agentic workflow, run

gh aw add githubnext/agentics/workflows/repo-assist.md@4bc8419fad05e6b032741cbfd189986700bcf71c