autogenerate enum validation methods

[josharian]

What do you want to change?

The codegen for enums generates a list of constants containing valid values:

type EnumType string

const (
	EnumTypeA EnumType = "A"
	EnumTypeB EnumType = "B"
)

When writing developer tools, it can be helpful to convert from a string value to an enum type. However, there is no exhaustive list of valid enum values, so we have to wait until a query fails to discover that an invalid enum value has been provided.

I'd like the codegen to also emit something like:

func (e EnumType) Valid() bool {
  switch e {
  case EnumTypeA, EnumTypeB:
    return true
  default:
    return false
  }
}

Then I can convert from string to enum type and check valid early on.

I know that this applies to PostgreSQL and Go. I'm not sure about MySQL and the other languages.

What database engines need to be changed?

PostgreSQL

What programming language backends need to be changed?

Go

[josharian]

On a related note, I find myself wanting to be able to list all available enum values.

[kevinburke1]

I have definitely opened a ticket for this previously, probably at least a year ago, agree it would be a good feature

On Wed, May 11, 2022 at 11:19 Josh Bleecher Snyder ***@***.***> wrote: On a related note, I find myself wanting to be able to list all available enum values. — Reply to this email directly, view it on GitHub <#1607 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AML53FNE33JXEDCEZBJZC5DVJP22BANCNFSM5VST2BLA> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

-- -- Kevin Burke phone: 925-271-7005 | kevin.burke.dev

[josharian]

The fix was easy: #1613. Feedback welcome.

I hope we can get it reviewed.

[kevinburke]

Ah, previously here: #447

I still think this is a good idea.