Failed to proxy request with ForwarderError: ResponseBodyDestination The response ended prematurely

[AndYggdrasil]

Investigative information

Please provide the following:

• Timestamp: 2025-03-28T12:35:19.4820329Z
• Function App version: v4
• Invocation ID: c4ecf110-2ad9-46fc-9880-0f21be5972b7
• Region: West Europe

Exception thrown on HttpTriggered function:
Exception while executing function: Functions.FunctionName Failed to proxy request with ForwarderError: ResponseBodyDestination The response ended prematurely, with at least 82 additional bytes expected. (ResponseEnded)

Repro steps

1. Function app project dependencies:

<PackageReference Include="Microsoft.ApplicationInsights.TraceListener" Version="2.23.0" />
<PackageReference Include="Microsoft.Azure.Functions.Extensions" Version="1.1.0" />
<PackageReference Include="Polly.Extensions.Http" Version="3.0.0" />
<PackageReference Include="Microsoft.Extensions.Http.Polly" Version="9.0.2" />
<PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Http" Version="3.3.0" />
<PackageReference Include="Microsoft.Azure.Functions.Worker.Sdk" Version="2.0.1" />
<PackageReference Include="Microsoft.Azure.Functions.Worker" Version="2.0.0" />
<PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Http.AspNetCore" Version="2.0.1" />
<PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.ServiceBus" Version="5.22.1" />
<PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Timer" Version="4.3.1" />
<PackageReference Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="9.0.2" />
<PackageReference Include="Microsoft.ApplicationInsights.WorkerService" Version="2.23.0" />
<PackageReference Include="Microsoft.Azure.Functions.Worker.ApplicationInsights" Version="2.0.0" />
<PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Http.AspNetCore" Version="2.0.1" />
<PackageReference Include="Microsoft.Azure.Functions.Worker" Version="2.0.0" />
<PackageReference Include="Microsoft.Azure.Functions.Worker.Sdk" Version="2.0.1" />

2. Call function app

Known workarounds

We have identified that upgrading to the newest version of the SDK packages solves this issue, however, then we run in to this issue #10575 , that suggests us to downgrade. That leads to a catch-22 situation.

Related information

I came across #10640 that suggests us to use .ConfigureFunctionsWebApplication(). However, we are already doing that.

[satvu]

@AndYggdrasil Looks like your app is still on host version 4.1036.x - the issue in #10575 is fixed in 4.1037. Please restart your app and let us know if you still run into that issue.

Edit: Additional info - the restart should force the latest host version to be picked up.

[AndYggdrasil]

@satvu We have performed several restarts and deployments during the day with no effect

…

________________________________ Fra: sarah ***@***.***> Sendt: fredag, marts 28, 2025 7:26:00 PM Til: Azure/azure-functions-host ***@***.***> Cc: AndYggdrasil ***@***.***>; Mention ***@***.***> Emne: Re: [Azure/azure-functions-host] Failed to proxy request with ForwarderError: ResponseBodyDestination The response ended prematurely (Issue #10969) [satvu]satvu left a comment (Azure/azure-functions-host#10969)<#10969 (comment)> @AndYggdrasil<https://github.com/AndYggdrasil> Looks like your app is still on host version 4.1036.x - the issue in #10575<#10575> is fixed in 4.1037. Please restart your app and let us know if you still run into that issue. — Reply to this email directly, view it on GitHub<#10969 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/BLGMOPGG4KLFM6W5PEKX6AL2WWH3HAVCNFSM6AAAAABZ7SGOU2VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDONRSGEZDENZSGA>. You are receiving this because you were mentioned.

[AndYggdrasil]

I have just performed a yet another new restart. It did not have any effect on the host version.

…

________________________________ From: sarah ***@***.***> Sent: Friday, March 28, 2025 7:25:55 PM To: Azure/azure-functions-host ***@***.***> Cc: AndYggdrasil ***@***.***>; Mention ***@***.***> Subject: Re: [Azure/azure-functions-host] Failed to proxy request with ForwarderError: ResponseBodyDestination The response ended prematurely (Issue #10969) @AndYggdrasil<https://github.com/AndYggdrasil> Looks like your app is still on host version 4.1036.x - the issue in #10575<#10575> is fixed in 4.1037. Please restart your app and let us know if you still run into that issue. — Reply to this email directly, view it on GitHub<#10969 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/BLGMOPGG4KLFM6W5PEKX6AL2WWH3HAVCNFSM6AAAAABZ7SGOU2VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDONRSGEZDENZSGA>. You are receiving this because you were mentioned.Message ID: ***@***.***> [satvu]satvu left a comment (Azure/azure-functions-host#10969)<#10969 (comment)> @AndYggdrasil<https://github.com/AndYggdrasil> Looks like your app is still on host version 4.1036.x - the issue in #10575<#10575> is fixed in 4.1037. Please restart your app and let us know if you still run into that issue. — Reply to this email directly, view it on GitHub<#10969 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/BLGMOPGG4KLFM6W5PEKX6AL2WWH3HAVCNFSM6AAAAABZ7SGOU2VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDONRSGEZDENZSGA>. You are receiving this because you were mentioned.Message ID: ***@***.***>

[satvu]

We'll get back to you on this - the image being pulled by your stamp doesn't seem to be up to date on host version.

[AndYggdrasil]

Thanks @satvu . We kindly request an update on this. The function is running on a P1v3 Linux plan, if that's any help?

[satvu]

@AndYggdrasil I'm closing this as a duplicate and using #10575 to track/publish updates instead. The team is still working on updating the host version for this plan.

[AndYggdrasil]

Hello. Please reopen this ticket. This issue has not resolved with the release of the new host version @satvu

[BYM-Henry]

@AndYggdrasil Hi, did you find a solution to this problem?

[AndYggdrasil]

@BYM-Henry Yes, in our case, it turned out that the client (Azure API Management Service SKU mtv1) did not properly support brotli-compression. We added middleware in APIM to remove the Accept-Encoding header from the request and then it worked on the function.