[Bug Report] Send message in batch to multiple outputs using ModuleClient throws

[wischi-chr]

Context

Context is very likely irrelevant

• OS: Windows 10 Desktop x64
• Application's .NET Target Framework : .net core 6
• Device: Laptop
• SDK version used: 1.42.2 (but also inspected the source of the latest main commit)

Description of the issue

The bug is almost exactly the same as described in #3201, but for me it happened with SendEventBatchAsync.

Sending a message to multiple outputs, or multiple times throws the following exception:
An item with the same key has already been added. Key: iothub-outputname

Looking at the source it seems that the fix (using the indexer to set the property) for #3201 was only applied to the SendEventAsync method. The method SendEventBatchAsync still uses .Add() and throws.

azure-iot-sdk-csharp/iothub/device/src/InternalClient.cs

Line 1573 in 9e445ce

messagesList.ForEach(m => m.SystemProperties.Add(MessageSystemPropertyNames.OutputName, outputName));

Would be great to fix it there too, I'm currently using reflection to remove the key before I call the ModuleClient - which is obviously not very pretty :-/

Thanks in advance

[timtay-microsoft]

#3441 should fix this for you

[wischi-chr]

Was shipped with 1.42.3 (release notes here) so I'm closing the issue.

Thanks for fixing it.