RicoSuter/NSwag

required field on response header spec not parsed correctly

Open

#2928 opened on Jun 29, 2020

View on GitHub
 (1 comment) (1 reaction) (0 assignees)C# (6,291 stars) (1,189 forks)batch import
help wantedproject: NSwag.Core.Yamltype: bug

Description

The following response header YAML definition gives an error while generating C# Core 3.1 code:

  responses:
    '200':
      description: OK
      headers:
        Last-Modified:
          description: The UTC datetime at when the item was last modified
          required: true
          schema:
            type: string

Exception: Newtonsoft.Json.JsonSerializationException: Error converting value "true" to type 'System.Collections.Generic.ICollection1[System.String]'. Path 'paths['/item/{id}'].head.responses.200.headers.Last-Modified.required', line 1, position 2518. ---> System.ArgumentException: Could not cast or convert from System.String to System.Collections.Generic.ICollection1[System.String].

It looks like the generator is expecting a string array, while the required parameter should be parsed as a boolean, just like path parameters

(version 13.6.2)

Contributor guide

Tech stack
csharp
Domain
backendtooling
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
under 1 hour
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
basic C# knowledgefamiliarity with JSON serialization
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
60
Research direction
The issue reports that the 'required' field in OpenAPI response headers is being parsed as a string array when it should be a boolean. This occurs in the NSwag code generation for C#. Look at how the path parameter 'required' field is handled for consistency. The relevant code is likely in the deserialization logic for OpenAPI response headers. A good starting point is to search for how 'required' is deserialized in the schema models.