Does this library support filtering on nested associations tables (joined tables fields)?

[acrolink]

No description provided.

[valyukov]

Sure, look at readme examples.

[acrolink]

I have tried something like this as outlined in the readme examples:

"comments_body_eq": "body",

But it is not working at all. I am using Phoenix 1.3 and suspect that this might be due to the newly introduced contexts.

[valyukov]

Could you please provide a full example or simple test that could help to reproduce issue? Because this example works fine for me.

[acrolink]

I have properties belonging to users. A property has a user_id field referencing it to a user. I tried to do users_name_cont but nothing happens.

[valyukov]

Did you expect that ex_sieve detect relation and make join instead of you? It doesn't work that way, you should make explicit join before apply ex_sieve filters.

[ekarak]

Actually, this functionality only works one level deep, and it would be immensely useful to filter on arbitrary nested fields. Right now, one can only do filters like parent_child_field_predicate and cannot do stuff like (grand+)parent_parent_child_field_predicate.
To give an example, in the typical Phoenix demo schema, there are Users that have_many Posts that have_many Comments. I'd like to be able to pass in a filter like
user_post_comment_text_cont=Elias to find all users whose posts have a comment that mention my name. I found that recursing into nested structs is stopping at the 1st descendant in ExSieve.Node.Attribute.get_name/2 here and recursion is possible by replacing get_name by extract:

  #defp get_name(%{related: module}, key), do: get_name(module, key)
  defp get_name(%{related: module}, key), do: extract(key, module)

... however things get messy after this as the dynamic_predicate function in Builder.Where needs to unroll the recursed Attributes returned. I've tried things like:

  # ekarak: recurse on higher-order nestings
  defp dynamic_predicate(pred, %Attribute{parent: parent, name: %Attribute{} = child}, value) do
    IO.inspect("pred=#{pred} parent=#{inspect(parent)} child=#{inspect(child)}", label: "dynamic_predicate -->")
    values = dynamic_predicate(pred, %Attribute{parent: child.parent, name: child.name}, value)
    |> IO.inspect(label: "values")
#    dynamic_predicate(pred, parent, values)
    dynamic([{^parent, p}], field(p, :id) in ^values)
    |> IO.inspect(label: "<-- dynamic_predicate #{inspect(parent)}")
  end

Any help appreciated, especially by @albertored who did changes here recently.

Thanks!

[albertored]

Hi @ekarak, as soon as I find some free time I will take a look at it

[albertored]

@ekarak I think I have something working, in the next days I will clean up the code a little bit a push it

[ekarak]

Thats great, thanks @albertored !

[albertored]

@ekarak I have just pushed a branch with the new feature, if you want you can give it a try

[ekarak]

thank you @albertored ! Will test asap

[ekarak]

This works beautifully! I want to test it a bit more (mainly to check for edge cases). @valyukov can you take a look as well?