Orchestration restart client API

[cgillum]

Durable Functions supports a RestartAsync API that makes it easy to restart an orchestration with the same input and either the same instance ID or a new instance ID. The implementation is here. This .NET SDK should also support this API.

[mronnblom-ith]

Any ETA on this? Restarting (and Rewinding) feels like rather important features, and support for .Net 6/in-process is very soon ending. So feature parity for isolated mode Durable Tasks should be a priority.

[jagmeet-chaudhary]

Hey folks, Any update on getting a rewind feature for dotnet isolated durable functions. I see this available for in process implementation and seems like an important feature for durable function as there is no way currently to rewind a failed process from failed state .Only thing that can be done is to restart but that requires re-running all steps.

[cgillum]

Unfortunately no updates at this time, but it is definitely on our radar. In the meantime, I’d recommend looking into using the rewind functionality exposed by our built-in HTTP APIs until we’re able to get this into the .NET Isolated SDK. https://learn.microsoft.com/en-us/azure/azure-functions/durable/durable-functions-http-api#rewind-instance-preview

[jagmeet-chaudhary]

Thanks, @cgillum. Based on your comment above, it seems there might be a gap in my understanding. Are you suggesting that we can use the rewind functionality using the HTTP API for isolated workers? In past our team members tried this, and it also didn't work but if it is supported using HTTP API we can relook at it.

[sastru]

How is the progress on this? support ending for net6 in-process is rapidly closing in at 10th November and we need to migrate our DurableTask Functions.... 🤦‍♂️

[cgillum]

@sastru regarding net6 support closing, if restart (or rewind) is a blocking issue for your ability to migrate to .NET Isolated, then you can instead migrate to net8 with the in-process worker. .NET in-process running on net8 will be supported through 2026.

https://azure.microsoft.com/en-us/updates/v2/azure-functions-supports-net8-using-in-process-model

[mronnblom-ith]

So for new applications needing Durable Functions with restart or rewind, Microsoft recommends to create a .Net 8 in-process application, which will then be tech debt from the very start and needing to be migrated to isolated mode quite soon?

Not to mention this statement (from here) which is quite far from the truth IMO:

I'm actually quite (unpleasantly) surprised about the immaturity of Azure Functions in general and isolated mode in particular.

(I fully understand that there are many different teams at Microsoft involved in this, and you don't have control over the others, but it's still very frustrating..)

[cgillum]

@mronnblom-ith I understand the frustration. We haven't done a good job of fully supporting the .NET Isolated worker model in Durable, but closing this gap is a major point of emphasis for us in the upcoming semester here on the DF team, so I'm optimistic that we'll get these migration issues addressed soon.

[mvansoens]

Hello, Any update on this? We're still waiting for the restart/retry functionality to be available in order to migrate.

[mvansoens]

Hello @mronnblom-ith any news on this? Were you guys able to work on this, blocking, issue? or should we look for alternatives to durable functions?