6.3.0 System.ArgumentException: Literal sections cannot contain the '?' character.

[spaasis]

Hi,

Recently updated from 6.2.1 to 6.3.0 and stuff started breaking. I'm running an OData controller via aspnet-api-versioning

Any endpoint within an OData controller with manually defined query parameters results in System.ArgumentException: The literal section 'QuantityUnits?onlyValid=' is invalid. Literal sections cannot contain the '?' character. (Parameter 'routeTemplate')

Controller and endpoint:

namespace WebApi.V1.CodeLists;

[ODataRoutePrefix("QuantityUnits")]
public class QuantityUnitsController : BaseODataController {
    [EnableQuery]
    [ProducesResponseType(typeof(ODataListWrapper<IQueryable<QuantityUnitOutput>>), Status200OK)]
    public async Task<IQueryable<QuantityUnitOutput>> Get(bool onlyValid = true) => ...
}

This works in 6.2.1. In 6.2.3 I observed that the swagger.json generation works, but the endpoint produced has a trailing {, e.g. /api/v1/odata/QuantityUnits{ which of course doesn't really work.

Any idea where to start digging?

Full stack trace:

[14:07:26 INF] Request starting HTTP/2 GET https://localhost:44395/swagger/v1/swagger.json - -
[14:07:26 ERR] An unhandled exception has occurred while executing the request.
System.ArgumentException: The literal section 'QuantityUnits?onlyValid=' is invalid. Literal sections cannot contain the '?' character. (Parameter 'routeTemplate')
 ---> Microsoft.AspNetCore.Routing.Patterns.RoutePatternException: The literal section 'QuantityUnits?onlyValid=' is invalid. Literal sections cannot contain the '?' character.
   at Microsoft.AspNetCore.Routing.Patterns.RoutePatternParser.Parse(String pattern)
   at Microsoft.AspNetCore.Routing.Patterns.RoutePatternFactory.Parse(String pattern)
   at Microsoft.AspNetCore.Routing.Template.TemplateParser.Parse(String routeTemplate)
   --- End of inner exception stack trace ---
   at Microsoft.AspNetCore.Routing.Template.TemplateParser.Parse(String routeTemplate)
   at Swashbuckle.AspNetCore.SwaggerGen.ApiDescriptionExtensions.RelativePathSansParameterConstraints(ApiDescription apiDescription)
   at Swashbuckle.AspNetCore.SwaggerGen.SwaggerGenerator.<>c.<GeneratePaths>b__6_0(ApiDescription apiDesc)
   at System.Linq.Lookup`2.Create(IEnumerable`1 source, Func`2 keySelector, IEqualityComparer`1 comparer)
   at System.Linq.GroupedEnumerable`2.GetEnumerator()
   at Swashbuckle.AspNetCore.SwaggerGen.SwaggerGenerator.GeneratePaths(IEnumerable`1 apiDescriptions, SchemaRepository schemaRepository)
   at Swashbuckle.AspNetCore.SwaggerGen.SwaggerGenerator.GetSwagger(String documentName, String host, String basePath)
   at Swashbuckle.AspNetCore.Swagger.SwaggerMiddleware.Invoke(HttpContext httpContext, ISwaggerProvider swaggerProvider)
   at Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.Authentication.AuthenticationMiddleware.Invoke(HttpContext context)
   at Hellang.Middleware.ProblemDetails.ProblemDetailsMiddleware.Invoke(HttpContext context)

[ruapho]

Same here. Works in Version 6.2.3 and breaks in 6.3.0.

[Sergey-Terekhin]

Same story

[spaasis]

Still happens in 6.3.1

[spaasis]

Some more diagnostics and a workaround:

Besides the explicit config in the opening post, the same issue is caused when an OData controller has a PATCH/POST/PUT that takes the parameters from query instead of request body:

    [HttpPatch]
    public async Task<ActionResult> Patch([FromQuery] MyCommand cmd) {

This causes the relative url to have ? and the error is thrown.

I worked around this myself by splitting these write operations to a different, non-odata controller

[spaasis]

Still broken in 6.4.0

[seriouz]

Still broken! Cannot define a route with [Route("api/test?id={var}")]

[icnocop]

Work-around:

1. Download build artifacts from https://github.com/domaindrivendev/Swashbuckle.AspNetCore/pull/2473: https://ci.appveyor.com/project/domaindrivendev/ahoy/builds/44347663/artifacts

Swashbuckle.AspNetCore.6.4.0-preview-2078.zip

2. Create/update NuGet.Config and point to local repository:

   <?xml version="1.0" encoding="utf-8"?>
   <configuration>
   <packageSources>
     <add key="nuget.org" value="https://api.nuget.org/v3/index.json" protocolVersion="3" />
     <add key="Local Swashbuckle.AspNetCore" value="..\..\..\Third Party\Swashbuckle\Swashbuckle.AspNetCore\6.4.0-preview-2078" />
   </packageSources>
   </configuration>

3. Update NuGet package references to use these packages instead.

[icnocop]

As another work-around, migrate to NSwag.AspNetCore and use the following document processor:

    using System.Collections.Generic;
    using System.Linq;
    using NJsonSchema;
    using NSwag;
    using NSwag.Generation.Processors;
    using NSwag.Generation.Processors.Contexts;

    /// <summary>
    /// Removes query string parameters from paths in the Open API specification document.
    /// </summary>
    /// <seealso cref="NSwag.Generation.Processors.IDocumentProcessor" />
    public class RemoveQueryStringParametersFromPathsDocumentProcessor : IDocumentProcessor
    {
        /// <inheritdoc/>
        public void Process(DocumentProcessorContext context)
        {
            List<string> pathsToFix = new List<string>();

            foreach (var path in context.Document.Paths)
            {
                if (path.Key.Contains('?'))
                {
                    pathsToFix.Add(path.Key);
                }
            }

            foreach (var pathToFix in pathsToFix)
            {
                string key = pathToFix[..pathToFix.IndexOf('?')];
                var pathItem = context.Document.Paths[pathToFix];
                if (context.Document.Paths.ContainsKey(key))
                {
                    context.Document.Paths[key].AddRange(pathItem);
                }
                else
                {
                    context.Document.Paths.Add(key, pathItem);
                }

                context.Document.Paths.Remove(pathToFix);
            }
        }
    }

Usage, in Startup.cs in ConfigureServices:

services.AddOpenApiDocument((settings, serviceProvider) =>
{
    settings.DocumentProcessors.Add(new RemoveQueryStringParametersFromPathsDocumentProcessor());
}

[JLeczycki]

It still exists in 6.5.0... Any solution for that for shawbuckle package?

[github-actions[bot]]

This issue is stale because it has been open for 60 days with no activity. It will be automatically closed in 14 days if no further updates are made.

[martincostello]

Community contributions to fix this are welcome.

Otherwise this will continue to be an issue as long as this issue is open.