Support default mode in SignalR Service emulator

[ADH-LukeBollam]

Is your feature request related to a problem? Please describe.

Our application consists of a main web app, and several supporting function apps. Users connect to signalr from the web app where they are assigned groups etc. The function apps send notifications to these groups when things complete.

• When running in Azure, each service connects to SignalR Service with the same connection string and now any service can send notifications to users.
• When running locally, we need to run it very differently. Each of the function apps needs to obtain authorization from the main application, then attempt to become a client of the main apps self-hosted SignalR. You need to write client methods for the services to call, and add more authorization to make sure only the services can call them and not users.

This means that

1. You have to write two different solutions for the same functionality.
2. You aren't debugging the same workflow as when you are running live so it's harder to validate that your code is working as expected.

Describe the solution you'd like

A local emulator that could run in place of the SignalR Service which supported default mode would allow apps to run exactly the same whether local or in Azure. A perfect example of this is Azurite, where you simply change the connection string and you have a fully working blob storage for debugging.

Additional context

[vicancy]

How about creating a free tier SignalR service for your local runs?

[ADH-LukeBollam]

It's an okay option, but a fully local development environment is preferable for a number of reasons.

• multiple developers will connect to the same SignalR Service and start sending notifications to each other that may not make sense when no other data is shared (eg. devs have their own local database and file storage)
• adds an online dependency to run a debug instance