is/will it be possible to have optional resource params?

[jahead]

Hey I've been using the resourceTypedParamsAndOutputs with great success and I know it in active development.

Is it or will it be possible to have optional resource params?

My use case is to have a module that will either create it's own 'standard' app service plan or allow the user of the module BYOD.

But afiak there is not a way to declare the resource param as optional. I've tried to find any discussion on this topic but can't find any.

What direction is the team thinking of going?

[jeskew]

It should eventually be possible to have optional resource parameters, but there's still some work that needs to be done to design the user experience. Unlike in-template resources or scalar parameters, I think optional resource parameters have to account for three different states:

1. A null value (e.g., an omitted value),
2. A non-null value that corresponds to a skipped resource (i.e., a resource with a false condition), or
3. A non-null value that corresponds to an active resource (one without a false condition).

We've put effort over the past year or so into the developer experience to make working with optional scalar parameters a more seamless experience, and there's been some discussion recently about how we can improve the experience in dealing with resources that may be skipped in a given deployment. I'm not sure anyone has yet looked into how those experiences will overlap.

[jahead]

Thanks for the context and the response, you're teams community engagement has been hugely appreciated and helpful.

Is the reason you need to have resource | false | null due to the the behavior of reference | update | ignore on a resource?

I'm just trying to picture writing a module where I'd want to know if a param was false | null I'm usually folding false -> null.

[jeskew]

Is the reason you need to have resource | false | null due to the the behavior of reference | update | ignore on a resource?

I'm just trying to picture writing a module where I'd want to know if a param was false | null I'm usually folding false -> null.

You're right that the vast majority of the time, the distinction between a false and null resource is probably not meaningful. The difference would primarily impact how you can use the resource-typed in expressions: <resource>.type and <resource>.apiVersion will work on any resource (omitted, disabled or otherwise); resources with a false condition can also support <resource>.name and <resource>.id, and any other property would only be available if the resource had a true condition (or no condition). I think we need to figure out whether that distinction would be meaningful for users.