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FunctionIndexingException thrown when same function method name is used in different classes

See original GitHub issue

Having a [ServiceBusTrigger] attribute Message parameter on one or methods with the same name, but in different classes, throws Microsoft.Azure.WebJobs.Host.Indexers.FunctionIndexingException: Error indexing method System.ArgumentException: An item with the same key has already been added. in FunctionIndexer.cs line 93 when the webjob console app starts.

It appears this broke from version 3.0.22 as 3.0.19 still works OK.

Repro steps

Create a Webjob console application and reference version >= 3.0.22.
Create two classes MessageOneHandler and MessageTwoHandler.
Add methods to each class with the same name and containing a ServiceBusTrigger attribute parameter: HandleMessage([ServiceBusTrigger(...)] Message message) {...}
Run the console application

Expected behavior

No exception is thrown and both methods are invoked for the service bus topic / queue they are configured to use.

Actual behavior

Exception above is thrown:

Microsoft.Azure.WebJobs.Host.Indexers.FunctionIndexingException: Error indexing method System.ArgumentException: An item with the same key has already been added. in FunctionIndexer.cs line 93:

   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 98
   at Microsoft.Azure.WebJobs.Host.Indexers.FunctionIndexProvider.CreateAsync(CancellationToken cancellationToken) in C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Indexers\FunctionIndexProvider.cs:line 95
   at Microsoft.Azure.WebJobs.Host.Indexers.FunctionIndexProvider.GetAsync(CancellationToken cancellationToken) in C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Indexers\FunctionIndexProvider.cs:line 69
   at Microsoft.Azure.WebJobs.Host.Executors.JobHostContextFactory.Create(JobHost host, CancellationToken shutdownToken, CancellationToken cancellationToken) in C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\Executors\JobHostContextFactory.cs:line 108
   at Microsoft.Azure.WebJobs.JobHost.InitializeHostAsync(CancellationToken cancellationToken, TaskCompletionSource`1 initializationTask) in C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\JobHost.cs:line 347
   at Microsoft.Azure.WebJobs.JobHost.StartAsyncCore(CancellationToken cancellationToken) in C:\projects\azure-webjobs-sdk-rqm4t\src\Microsoft.Azure.WebJobs.Host\JobHost.cs:line 97
   at Microsoft.Extensions.Hosting.Internal.Host.StartAsync(CancellationToken cancellationToken)
   at Microsoft.Extensions.Hosting.HostingAbstractionsHostExtensions.RunAsync(IHost host, CancellationToken token)
   at Microsoft.Extensions.Hosting.HostingAbstractionsHostExtensions.RunAsync(IHost host, CancellationToken token)
   at StudyTravel.File.ServiceBus.Subscribers.Program.Main() in /home/dan/projects/StudyTravel/File/src/StudyTravel.File.ServiceBus.Subscribers/Program.cs:line 51
   at StudyTravel.File.ServiceBus.Subscribers.Program.<Main>()

Known workarounds

Use a unique name per method even if in different classes e.g.

public class MessageOneHandler
{
    public async Task HandleMessageOne([ServiceBusTrigger(...) Message message) {...}
}

public class MessageTwoHandler
{
    public async Task HandleMessageTwo([ServiceBusTrigger(...) Message message) {...}
}