7 replies

Setting attributes after getting data in before_transaction - calling validation in change_attribute

I have a

User

User

resource which requires email and a name. I want to expose a create type action on this resource, but all I have available when calling the action is a token. That token is in a 3rd party system, which returns the name and email. This resource has global validation on name and email, which I'd rather not change (or mark as

before_action?: true

before_action?: true

) since I do want them to be run up front for other actions.

What I was hoping to do is in a

before_transaction

before_transaction

block, make the API call to get the data and set the attributes with

change_attribute

change_attribute

, or put them in a context and call

set_attribute

set_attribute

in a change block. However, when I do this, since the initial changeset doesn't have an email, it fails validation and the before_transaction never runs. If I pass in a placeholder email, I can get the

before_transaction

before_transaction

to run, but then I get warnings when calling

change_attribute

change_attribute

because the changeset has already been validated, and it's actually possible to pass in a bad email here and it'll get written to the database.

Another idea I had was to try and do this as a generic action, and then in the run block I would make the API call, get the user data, and then manually call the existing

:create

:create

. However, I need to return metadata (access tokens) for the user, but it seems like generic actions don't allow for metadata blocks, and since this action will be exposed via GraphQL, I'd want that typing of the metadata attributes on the query/mutation.

Basically, I want to expose an action on a user resource that accepts a token as an argument, turns that into

user_info

user_info

and

oauth_tokens

oauth_tokens

and then can do the equivalent of the

:register_with_google

:register_with_google

action in the Ash Authentication docs, returning the access token for the user as a metadata field.

Note, I'll never really call this in a form, so I'm ok if the fields don't get validated until writing to the persistence layer (postgres in my case), but I do want them to be validated at some point.

Solution

I think this is what you want https://hexdocs.pm/ash/dsl-ash-resource.html#actions-create-delay_global_validations? ?

Jump to solution