I execute a very simple Function App to Docker with this Dockerfile

using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Azure.WebJobs;
using Microsoft.Azure.WebJobs.Extensions.Http;
using System.IO;
using System.Net.Http;
using System.Threading.Tasks;

namespace fapp1
{
    public static class HttpIngress
    {
        [FunctionName("Health")]
        public static IActionResult Health([HttpTrigger(AuthorizationLevel.Anonymous, "get", Route = "health")] HttpRequest req) => new OkObjectResult("OK");

        [FunctionName("HttpIngress")]
        [return: ServiceBus("%queuename%", Connection = "servicebusconnection")]
        public static async Task<string> Run(
            [HttpTrigger(AuthorizationLevel.Anonymous, "post")] HttpRequest req)
            => await new StreamReader(req.Body).ReadToEndAsync();
    }
}

FROM mcr.microsoft.com/dotnet/sdk:6.0 AS installer-env

# Build requires 3.1 SDK
COPY --from=mcr.microsoft.com/dotnet/core/sdk:3.1 /usr/share/dotnet /usr/share/dotnet

COPY . /src/dotnet-function-app
RUN cd /src/dotnet-function-app && \
    mkdir -p /home/site/wwwroot && \
    dotnet publish *.csproj --output /home/site/wwwroot

# To enable ssh & remote debugging on app service change the base image to the one below
# FROM mcr.microsoft.com/azure-functions/dotnet:4-appservice
FROM mcr.microsoft.com/azure-functions/dotnet:4
ENV AzureWebJobsScriptRoot=/home/site/wwwroot \
    AzureFunctionsJobHost__Logging__Console__IsEnabled=true

COPY --from=installer-env ["/home/site/wwwroot", "/home/site/wwwroot"]

docker run -it --env-file docker.env test

For both Functions in HttpIngress I get this error:

fail: Host.Startup[0]
      Error indexing method 'Health'
      Microsoft.Azure.WebJobs.Host.Indexers.FunctionIndexingException: Error indexing method 'Health'
       ---> System.InvalidOperationException: Method overloads are not supported. There are multiple methods with the name 'fapp1.HttpIngress.Health'.
         at Microsoft.Azure.WebJobs.Host.Indexers.FunctionIndex.Add(IFunctionDefinition function, FunctionDescriptor descriptor, MethodInfo method) in C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Indexers\FunctionIndex.cs:line 30
         at Microsoft.Azure.WebJobs.Host.Indexers.FunctionIndexer.IndexMethodAsyncCore(MethodInfo method, IFunctionIndexCollector index, CancellationToken cancellationToken) in C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Indexers\FunctionIndexer.cs:line 349
         at Microsoft.Azure.WebJobs.Host.Indexers.FunctionIndexer.IndexMethodAsync(MethodInfo method, IFunctionIndexCollector index, CancellationToken cancellationToken) in C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Indexers\FunctionIndexer.cs:line 149
         --- End of inner exception stack trace ---
         at Microsoft.Azure.WebJobs.Host.Indexers.FunctionIndexer.IndexMethodAsync(MethodInfo method, IFunctionIndexCollector index, CancellationToken cancellationToken) in C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Indexers\FunctionIndexer.cs:line 157
         at Microsoft.Azure.WebJobs.Host.Indexers.FunctionIndexer.IndexTypeAsync(Type type, IFunctionIndexCollector index, CancellationToken cancellationToken) in C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Indexers\FunctionIndexer.cs:line 85
fail: Function.Health[0]
      Microsoft.Azure.WebJobs.Host: Error indexing method 'Health'. Microsoft.Azure.WebJobs.Host: Method overloads are not supported. There are multiple methods with the name 'fapp1.HttpIngress.Health'.
warn: Host.Startup[0]
      Function 'Health' failed indexing and will be disabled.

I tried

• changing from static class and methods to instance : no effect
• putting each Function/method into separate classes : this worked, but this could merely be a work around
• switching Microsoft.NET.Sdk.Functions between 4.0.1 (set by default on func init --worker-runtime dotnet --docker --language c#) and current 4.1.0 : no effect

I now run Functions in container for years but right now cannot figure out what I miss.

CodePudding user response：

I found your question as I had the same issue. It may have something to do with this:

https://github.com/Azure/azure-functions-host/issues/8244

Based on the info within the link I changed my dockerfile to use this image for azure functions:

FROM mcr.microsoft.com/azure-functions/dotnet:4.1.3-slim 

This got it working for me