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Async Dependency Initialization with requireValue (Riverpod)

How do you initialize an async dependency during app startup, and use it synchronously afterwards?

With Riverpod, this is done in 3 simple steps:

1. Declare it inside a FutureProvider
2. Initialize it inside main()
3. Use requireValue afterwards

Details in thread below 🧵

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The key steps are to:

• declare and initialize the dependency inside a FutureProvider
• access the dependency with requireValue whenever needed (inside other providers or widgets)

But requireValue will throw unless there is a value already.

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To address this, we can create a ProviderContainer inside main() and await until the FutureProvider is initialized.

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As a result, any providers or widgets that depend (directly or indirectly) on the original FutureProvider only contain synchronous code.

So no await or .when is needed.

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I used to solve this problem by:

• throwing an UnimplementedError inside the FutureProvider
• initializing the dependency with a provider override inside main()

But this approach much nicer and easier to follow. 🙂

Happy coding!

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