Ash Elixir•3y ago

Create Resource without relation

Hey guys, I'm dipping my toes into Ash and try to build a small thing, but now I'm stuck. I created a resource and a relationship. I want to create the resource, but the relationship can be empty. But when I try to create the resource, I get this error:

iex(5)> Inventizr.Inventory.Item |> Ash.Changeset.for_create(:new, %{model: "MacBook", brand: "Apple"}) |> Inventizr.Inventory.create!()
[debug] QUERY OK db=2.3ms idle=1636.8ms
begin []
[debug] QUERY OK db=2.4ms
rollback []
** (UndefinedFunctionError) function Ash.NotLoaded.__changeset__/0 is undefined or private
    (ash 2.5.10) Ash.NotLoaded.__changeset__()
    (ecto 3.9.4) lib/ecto/changeset.ex:409: Ecto.Changeset.change/2
    (ecto 3.9.4) lib/ecto/changeset/relation.ex:173: Ecto.Changeset.Relation.do_change/4
    (ecto 3.9.4) lib/ecto/changeset/relation.ex:335: Ecto.Changeset.Relation.single_change/5
    (ecto 3.9.4) lib/ecto/changeset/relation.ex:165: Ecto.Changeset.Relation.change/3
...

iex(5)> Inventizr.Inventory.Item |> Ash.Changeset.for_create(:new, %{model: "MacBook", brand: "Apple"}) |> Inventizr.Inventory.create!()
[debug] QUERY OK db=2.3ms idle=1636.8ms
begin []
[debug] QUERY OK db=2.4ms
rollback []
** (UndefinedFunctionError) function Ash.NotLoaded.__changeset__/0 is undefined or private
    (ash 2.5.10) Ash.NotLoaded.__changeset__()
    (ecto 3.9.4) lib/ecto/changeset.ex:409: Ecto.Changeset.change/2
    (ecto 3.9.4) lib/ecto/changeset/relation.ex:173: Ecto.Changeset.Relation.do_change/4
    (ecto 3.9.4) lib/ecto/changeset/relation.ex:335: Ecto.Changeset.Relation.single_change/5
    (ecto 3.9.4) lib/ecto/changeset/relation.ex:165: Ecto.Changeset.Relation.change/3
...

The resource is defined as:

defmodule Inventizr.Inventory.Item do
  use Ash.Resource,
    data_layer: AshPostgres.DataLayer

  attributes do
    uuid_primary_key :id

    attribute :brand, :string
    attribute :model, :string

    attribute :status, :atom do
      constraints one_of: [:available, :in_use, :defect, :unavailable]
      default :available
      allow_nil? false
    end
  end

  relationships do
    belongs_to :user, Inventizr.Accounts.User do
      api Inventizr.Accounts
      allow_nil? true
    end
  end
end

defmodule Inventizr.Inventory.Item do
  use Ash.Resource,
    data_layer: AshPostgres.DataLayer

  attributes do
    uuid_primary_key :id

    attribute :brand, :string
    attribute :model, :string

    attribute :status, :atom do
      constraints one_of: [:available, :in_use, :defect, :unavailable]
      default :available
      allow_nil? false
    end
  end

  relationships do
    belongs_to :user, Inventizr.Accounts.User do
      api Inventizr.Accounts
      allow_nil? true
    end
  end
end

And the corresponding relation:

  attributes do
    uuid_primary_key :id
    attribute :name, :string
  end

  relationships do
    has_many :items, Inventizr.Inventory.Item do
      api Inventizr.Inventory
    end
  end
end

  attributes do
    uuid_primary_key :id
    attribute :name, :string
  end

  relationships do
    has_many :items, Inventizr.Inventory.Item do
      api Inventizr.Inventory
    end
  end
end

I can't figure out, what I'm doing wrong, because it works like this in the getting started guide: https://ash-hq.org/docs/guides/ash/latest/tutorials/get-started#working-with-relationships. I'm sure I'm missing something obvious...

Ash HQ

Guide: Get Started

Read the "Get Started" guide on Ash HQ

21 Replies

frankdugan3•3y ago

Welcome! 👋 Is the first resource the full definition?

ZachDaniel•3y ago

...perhaps I broke something with the relationship -> assoc interop?? @fummmp can you post more of the stacktrace? @frankdugan3 have you tried out your app against the new branch with this interop? sorry, the new release 🙂 not on a branch

frankdugan3•3y ago

Not the large app. The small app I'm working on that's up to date, don't think I have any belongs_to that can be nil. Otherwise, haven't noticed any problems yet.

ZachDaniel•3y ago

welp ash_postgres tests are failing with the new ash changes, oops with that same error

frankdugan3•3y ago

Ooh, ouch! lol

ZachDaniel•3y ago

will fix now

fummmpOP•3y ago

Sure

** (UndefinedFunctionError) function Ash.NotLoaded.__changeset__/0 is undefined or private
    (ash 2.5.10) Ash.NotLoaded.__changeset__()
    (ecto 3.9.4) lib/ecto/changeset.ex:409: Ecto.Changeset.change/2
    (ecto 3.9.4) lib/ecto/changeset/relation.ex:173: Ecto.Changeset.Relation.do_change/4
    (ecto 3.9.4) lib/ecto/changeset/relation.ex:335: Ecto.Changeset.Relation.single_change/5
    (ecto 3.9.4) lib/ecto/changeset/relation.ex:165: Ecto.Changeset.Relation.change/3
    (ecto 3.9.4) lib/ecto/changeset/relation.ex:542: anonymous fn/4 in Ecto.Changeset.Relation.surface_changes/3
    (elixir 1.14.3) lib/enum.ex:2468: Enum."-reduce/3-lists^foldl/2-0-"/3
    (ecto 3.9.4) lib/ecto/changeset/relation.ex:529: Ecto.Changeset.Relation.surface_changes/3
    (ecto 3.9.4) lib/ecto/repo/schema.ex:336: Ecto.Repo.Schema.do_insert/4
    (ash_postgres 1.3.3) lib/data_layer.ex:1018: AshPostgres.DataLayer.create/2
    (ash 2.5.10) lib/ash/actions/create.ex:415: anonymous fn/8 in Ash.Actions.Create.as_requests/5
    (ash 2.5.10) lib/ash/changeset/changeset.ex:1588: Ash.Changeset.run_around_actions/2
    (ash 2.5.10) lib/ash/actions/create.ex:317: anonymous fn/9 in Ash.Actions.Create.as_requests/5
    (ash 2.5.10) lib/ash/engine/request.ex:1028: Ash.Engine.Request.do_try_resolve_local/4
    (ash 2.5.10) lib/ash/engine/request.ex:282: Ash.Engine.Request.do_next/1
    (ash 2.5.10) lib/ash/engine/request.ex:211: Ash.Engine.Request.next/1
    (ash 2.5.10) lib/ash/engine/engine.ex:650: Ash.Engine.advance_request/2
    (ash 2.5.10) lib/ash/engine/engine.ex:556: Ash.Engine.fully_advance_request/2
    (ash 2.5.10) lib/ash/engine/engine.ex:497: Ash.Engine.do_run_iteration/2
    iex:5: (file)

** (UndefinedFunctionError) function Ash.NotLoaded.__changeset__/0 is undefined or private
    (ash 2.5.10) Ash.NotLoaded.__changeset__()
    (ecto 3.9.4) lib/ecto/changeset.ex:409: Ecto.Changeset.change/2
    (ecto 3.9.4) lib/ecto/changeset/relation.ex:173: Ecto.Changeset.Relation.do_change/4
    (ecto 3.9.4) lib/ecto/changeset/relation.ex:335: Ecto.Changeset.Relation.single_change/5
    (ecto 3.9.4) lib/ecto/changeset/relation.ex:165: Ecto.Changeset.Relation.change/3
    (ecto 3.9.4) lib/ecto/changeset/relation.ex:542: anonymous fn/4 in Ecto.Changeset.Relation.surface_changes/3
    (elixir 1.14.3) lib/enum.ex:2468: Enum."-reduce/3-lists^foldl/2-0-"/3
    (ecto 3.9.4) lib/ecto/changeset/relation.ex:529: Ecto.Changeset.Relation.surface_changes/3
    (ecto 3.9.4) lib/ecto/repo/schema.ex:336: Ecto.Repo.Schema.do_insert/4
    (ash_postgres 1.3.3) lib/data_layer.ex:1018: AshPostgres.DataLayer.create/2
    (ash 2.5.10) lib/ash/actions/create.ex:415: anonymous fn/8 in Ash.Actions.Create.as_requests/5
    (ash 2.5.10) lib/ash/changeset/changeset.ex:1588: Ash.Changeset.run_around_actions/2
    (ash 2.5.10) lib/ash/actions/create.ex:317: anonymous fn/9 in Ash.Actions.Create.as_requests/5
    (ash 2.5.10) lib/ash/engine/request.ex:1028: Ash.Engine.Request.do_try_resolve_local/4
    (ash 2.5.10) lib/ash/engine/request.ex:282: Ash.Engine.Request.do_next/1
    (ash 2.5.10) lib/ash/engine/request.ex:211: Ash.Engine.Request.next/1
    (ash 2.5.10) lib/ash/engine/engine.ex:650: Ash.Engine.advance_request/2
    (ash 2.5.10) lib/ash/engine/engine.ex:556: Ash.Engine.fully_advance_request/2
    (ash 2.5.10) lib/ash/engine/engine.ex:497: Ash.Engine.do_run_iteration/2
    iex:5: (file)

Thank you for the quick reply! It's mostly complete but here's the full module

defmodule Inventizr.Inventory.Item do
  use Ash.Resource,
    data_layer: AshPostgres.DataLayer,
    extensions: [AshAdmin.Resource]

  postgres do
    table "items"
    repo Inventizr.Repo
  end

  actions do
    defaults [:create, :read, :update, :destroy]

    read :list do
      description "lists all the items"
      prepare build(sort: [inserted_at: :desc])
    end

    create :new do
      accept [:model, :brand]
    end
  end

  attributes do
    uuid_primary_key :id

    attribute :brand, :string
    attribute :model, :string

    attribute :status, :atom do
      constraints one_of: [:available, :in_use, :defect, :unavailable]
      default :available
      allow_nil? false
    end
  end

  relationships do
    belongs_to :user, Inventizr.Accounts.User do
      api Inventizr.Accounts
      attribute_writable? true
      allow_nil? true
    end
  end

  code_interface do
    define_for Inventizr.Inventory
    define :list, action: :read
    define :new
  end
end

defmodule Inventizr.Inventory.Item do
  use Ash.Resource,
    data_layer: AshPostgres.DataLayer,
    extensions: [AshAdmin.Resource]

  postgres do
    table "items"
    repo Inventizr.Repo
  end

  actions do
    defaults [:create, :read, :update, :destroy]

    read :list do
      description "lists all the items"
      prepare build(sort: [inserted_at: :desc])
    end

    create :new do
      accept [:model, :brand]
    end
  end

  attributes do
    uuid_primary_key :id

    attribute :brand, :string
    attribute :model, :string

    attribute :status, :atom do
      constraints one_of: [:available, :in_use, :defect, :unavailable]
      default :available
      allow_nil? false
    end
  end

  relationships do
    belongs_to :user, Inventizr.Accounts.User do
      api Inventizr.Accounts
      attribute_writable? true
      allow_nil? true
    end
  end

  code_interface do
    define_for Inventizr.Inventory
    define :list, action: :read
    define :new
  end
end

ZachDaniel•3y ago

Should have a new version of ash_postgres in with a fix soon fix in v1.3.4

fummmpOP•3y ago

@Zach Daniel you are amazing!

ZachDaniel•3y ago

😆 thanks for the kind words. Thanks for reporting the issue so we could fix it quickly. If your issue has been resolved, please add the Solved tag and close this thread by right clicking the thread in the sidebar and choosing Close Post.

fummmpOP•3y ago

I saw part 1 of the video yesterday and it finally made me try Ash. Excited for part 2! 🎉

ZachDaniel•3y ago

Well you're in luck: https://discord.com/channels/711271361523351632/1068688488083492885 🥳

fummmpOP•3y ago

Oh wow! You absolutely made my day now! ❤️ Will try tomorrow! Now I need some sleep..it’s 3AM here in Germany 🙈

ZachDaniel•3y ago

😆 go to bed

fummmpOP•3y ago

@Zach Daniel you're my hero! It works! Thank you again for the more than quick response and the effort to fix the bug immediately!

waseigo•3y ago

Hi @fummmp, quick question: in the belongs_to relationship, why do you add the line starting with api? Also, does attribute_writable? true make the relationship capable of being defined by passing the relevant ..._id during the :create action?

waseigo•3y ago

On https://www.ash-hq.org/docs/guides/ash/latest/topics/relationships.md there is no such api line explained.

Ash HQ

Guide: Relationships

Read the "Relationships" guide on Ash HQ

barnabasj•3y ago

You can have different API modules per e.g domain. If the related items are in configured in APIs you need to tell Ash which one to use.

ZachDaniel•3y ago

https://ash-hq.org/docs/dsl/ash/latest/resource/relationships/has_many

Ash HQ

DSL Entity: ash > Resource > relationships > has_many

View the documentation for DSL Entity: ash > Resource > relationships > has_many on Ash HQ.

ZachDaniel•3y ago

in the DSL docs we explain each individual option

waseigo•3y ago

@barnabasj aha, so if I only have one domain, then I don't need it -- but, e.g., if I wanted to make a relationship between the resource in my domain and a resource in ash_authentication's accounts domain, then I use the api option? got it, thanks!

Gaming

Programming

Create Resource without relation

Did you find this page helpful?