Explained Blazor Server specifics for configuring-dbcontext.md

[akovac35]

For Blazor Server hosting model, one logical request is used for maintaining the Blazor user circuit, and thus only one scoped DbContext instance is available per user circuit if the default injection scope is used.

[roji]

Thanks for this - ideally guidance would be provided for how to deal with this, including samples (e.g. register the context as transient?). Also, we'd need to document the situation for client-side Blazor, not just server-side.

Finally, this guidance probably belongs more on the ASP.NET side, with links from EF Core.

[smitpatel]

Should live as tutorial alongside this https://docs.microsoft.com/en-us/aspnet/core/data/ef-rp/intro?view=aspnetcore-3.1&tabs=visual-studio

[akovac35]

Thanks for this - ideally guidance would be provided for how to deal with this, including samples (e.g. register the context as transient?). Also, we'd need to document the situation for client-side Blazor, not just server-side.

Finally, this guidance probably belongs more on the ASP.NET side, with links from EF Core.

Guidance is already provided just a few lines down from my update:

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However any code that explicitly executes multiple threads in parallel should ensure that DbContext instances aren't ever accessed concurrently.

Using dependency injection, this can be achieved by either registering the context as scoped and creating scopes (using IServiceScopeFactory) for each thread, or by registering the DbContext as transient (using the overload of AddDbContext which takes a ServiceLifetime parameter).

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It makes sense to have Blazor specific detail mentioned on this particular page. Perhaps my one-line suggestion could be rewritten to be more generic (other changes should remain for consistency):

A specific use case where additional consideration is required is scoped dependency injection in Blazor applications: ASP.NET Core Blazor dependency injection

[ajcvickers]

@akovac35 Thanks for submitting this. We're going to merge it because it improves what we currently have. However, #2025 covers having much better guidance here.