Create generic action that returns own resource fails to compile

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1

I noticed that when creating a generic action that should return the same resource inside an array fails to compile.

For example, I have this generic function:

    action :search, {:array, SkipTraceEntity} do
      argument :first_name, :string, allow_nil?: false
      argument :last_name, :string, allow_nil?: false

      run &Actions.Search.run/2
    end

This action is defined inside the SkipTraceEntity resource.

This will give the following compile error:

== Compilation error in file lib/pacman/markets/skip_trace_entity.ex ==
** (RuntimeError) {:array, Pacman.Markets.SkipTraceEntity} is not a valid type.

If I change SkipTraceEntity with any other resource, it works.

2

That’s correct. This is because the struct is still being compiled at the time the DSL is being evaluated. The work around is to use a :struct type with an :instance_of constraint. Eg:

    action :search, {:array, :struct} do
      constraints instance_of: SkipTraceEntity
      argument :first_name, :string, allow_nil?: false
      argument :last_name, :string, allow_nil?: false

      run &Actions.Search.run/2
    end
2 Likes
3

Hey @jimsynz , thanks for reply.

I just tested that solution, but it doesn’t seem to work, I get the following error:

== Compilation error in file lib/pacman/markets/skip_trace_entity.ex ==
** (Spark.Error.DslError) [Pacman.Markets.SkipTraceEntity]
 actions -> action -> search:
  unknown options [:instance_of], valid options are: [:min_length, :max_length, :nil_items?, :empty_values]
    lib/pacman/markets/skip_trace_entity.ex:95: (module)
4

Oh shit, you’re right. It’s an array of structs. Looks like Zach thought of this case and you can do constraints items: [instance_of: SkipTraceEntity].

5

Seem like that worked, but just a quick correction, the array should be a keyword, so instance_of is missing a : at the end.

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