Nested errors do not propagate

[honungsburk]

I'm encountering an issue with the access behavior in nested Ecto schemas that produce nested changesets. While errors in the top-level struct propagate as expected, errors within nested structs do not appear to propagate correctly, even though the values do.

defmodule Settings do
  use Ecto.Schema
  import Ecto.Changeset

  @primary_key false
  embedded_schema do
    field :field_one, :string
    embeds_one :field_two, NestedSetting
  end

  def changeset(settings, attrs \\ %{}) do
    settings
    |> cast(attrs, [:field_one])
    |> cast_embed(:field_two)
    |> validate_length(:field_one, min: 2)
  end
end

defmodule NestedSetting do
  use Ecto.Schema
  import Ecto.Changeset

  @primary_key false
  embedded_schema do
    field :nested_field, :string
  end

  def changeset(nested_setting, attrs \\ %{}) do
    nested_setting
    |> cast(attrs, [:nested_field])
    |> validate_required([:nested_field])
  end
end

Accessed like so

<.form 
  id="settings-form"
  :let={form}
  for={@settings_form}
  as={:settings}
  phx-change="validate"
  phx-submit="save"
>
  <div class="flex flex-col gap-6 mt-8">
    <%!-- Settings Information --%>
    <.section title="Settings Information" description="Main settings fields">
      <.input_list>
        <:item for="field_one" title="Field One" description="Main field in settings">
          <.input
            id="field-one"
            field={form[:field_one]}
            type="text"
            autocomplete="off"
            phx-debounce="blur"
          />
        </:item>
      </.input_list>
    </.section>

    <%!-- Nested Settings --%>
    <.inputs_for :let={nested_form} field={form[:field_two]}>
      <.section title="Nested Settings" description="Additional nested settings fields">
        <.input_list>
          <:item for="nested_field" title="Nested Field" description="Field inside nested settings">
            <.input
              id="nested-field"
              field={nested_form[:nested_field]}
              type="text"
              autocomplete="off"
              phx-debounce="blur"
            />
          </:item>
        </.input_list>
      </.section>
    </.inputs_for>
  </div>

  <div class="mt-4">
    <.button type="submit">Save Settings</.button>
  </div>
</.form>

How I validate:

@impl true
def handle_event("validate", %{"settings" => settings_params}, socket) do
  form =
    %Settings{}
    |> Settings.changeset(settings_params)
    |> to_form(as: :settings, action: :validate)

  {:noreply,
   socket
   |> assign(:settings_form, form)
  }
end

When I inspect the values it seems that the access behavior doesn't propagate the errors correctly

[honungsburk]

Here is a concrete example of the output from the first the top level form, then a subfield called company_settings and then inactive_connect_session_timeout_hours.

form:

%Phoenix.HTML.Form{
  source: #Ecto.Changeset<
    action: :validate,
    changes: %{
      group: "Indeez",
      language: "fr_FR",
      display_name: "Test Company 22",
      interface_settings: "{\"we\":\"jy\"}",
      company_name: "Test Company",
      company_settings: #Ecto.Changeset<
        action: :insert,
        changes: %{
          freemium: false,
          valuation_parameters: #Ecto.Changeset<
            action: :insert,
            changes: %{
              preferred_store_price: "median",
              all_refurbished_stores: false
            },
            errors: [],
            data: #Runar.CompanySettings.ValuationParameters<>,
            valid?: true,
            ...
          >,
          single_sign_on: #Ecto.Changeset<
            action: :insert,
            changes: %{
              type: "saml",
              parameters: #Ecto.Changeset<action: :insert, changes: %{},
               errors: [], data: #Runar.CompanySettings.SingleSignOnParams<>,
               valid?: true, ...>
            },
            errors: [],
            data: #Runar.CompanySettings.SingleSignOn<>,
            valid?: true,
            ...
          >,
          inactive_connect_session_timeout_hours: -1
        },
        errors: [
          inactive_connect_session_timeout_hours: {"must be greater than %{number}",
           [validation: :number, kind: :greater_than, number: 0]}
        ],
        data: #Runar.CompanySettings<>,
        valid?: false,
        ...
      >,
      market: "FR",
      timezone: "Europe/Paris"
    },
    errors: [],
    data: #Runar.CompanyForm<>,
    valid?: false,
    ...
  >,
  impl: Phoenix.HTML.FormData.Ecto.Changeset,
  id: "company-form",
  name: "form",
  data: %Runar.CompanyForm{
    active: true,
    display_name: nil,
    company_name: nil,
    language: nil,
    market: nil,
    group: nil,
    statistics_enabled: false,
    timezone: nil,
    interface_settings: "{}",
    company_settings: nil
  },
  action: nil,
  hidden: [],
  params: %{
    "_unused_company_name" => "",
    "_unused_display_name" => "",
    "_unused_group" => "",
    "_unused_interface_settings" => "",
    "_unused_language" => "",
    "_unused_market" => "",
    "_unused_statistics_enabled" => "",
    "_unused_timezone" => "",
    "company_name" => "Test Company",
    "company_settings" => %{
      "_persistent_id" => "0",
      "_unused_force_connect_logout_session_hours" => "",
      "_unused_freemium" => "",
      "_unused_max_concurrent_connect_logins" => "",
      "force_connect_logout_session_hours" => "",
      "freemium" => "false",
      "inactive_connect_session_timeout_hours" => "-1",
      "max_concurrent_connect_logins" => "",
      "single_sign_on" => %{
        "_persistent_id" => "0",
        "_unused_connected_domains" => "",
        "_unused_type" => "",
        "_unused_version" => "",
        "connected_domains" => "",
        "parameters" => %{
          "_persistent_id" => "0",
          "_unused_button_text" => "",
          "_unused_idp" => "",
          "button_text" => "",
          "idp" => ""
        },
        "type" => "saml",
        "version" => ""
      },
      "valuation_parameters" => %{
        "_persistent_id" => "0",
        "_unused_all_refurbished_stores" => "",
        "_unused_preferred_store_price" => "",
        "all_refurbished_stores" => "false",
        "preferred_store_price" => "median"
      }
    },
    "display_name" => "Test Company 22",
    "group" => "Indeez",
    "interface_settings" => "{\"we\":\"jy\"}",
    "language" => "fr_FR",
    "market" => "FR",
    "statistics_enabled" => "false",
    "timezone" => "Europe/Paris"
  },
  errors: [],
  options: [
    method: "post",
    id: "company-form",
    multipart: false,
    "phx-submit": "save",
    "phx-change": "validate"
  ],
  index: nil
}

company_settings:

%Phoenix.HTML.Form{
  source: #Ecto.Changeset<
    action: nil,
    changes: %{
      freemium: false,
      valuation_parameters: #Ecto.Changeset<
        action: :insert,
        changes: %{
          preferred_store_price: "median",
          all_refurbished_stores: false
        },
        errors: [],
        data: #Runar.CompanySettings.ValuationParameters<>,
        valid?: true,
        ...
      >,
      single_sign_on: #Ecto.Changeset<
        action: :insert,
        changes: %{
          type: "saml",
          parameters: #Ecto.Changeset<action: :insert, changes: %{}, errors: [],
           data: #Runar.CompanySettings.SingleSignOnParams<>, valid?: true, ...>
        },
        errors: [],
        data: #Runar.CompanySettings.SingleSignOn<>,
        valid?: true,
        ...
      >,
      inactive_connect_session_timeout_hours: -1
    },
    errors: [
      inactive_connect_session_timeout_hours: {"must be greater than %{number}",
       [validation: :number, kind: :greater_than, number: 0]}
    ],
    data: #Runar.CompanySettings<>,
    valid?: false,
    ...
  >,
  impl: Phoenix.HTML.FormData.Ecto.Changeset,
  id: "company-form_company_settings_0",
  name: "form[company_settings]",
  data: %Runar.CompanySettings{
    claim_link_ai_group_suggestion: nil,
    claim_link_default_expiration: nil,
    claim_link_direct_enabled: nil,
    claim_link_disabled_email_notifications: nil,
    claim_link_enabled: nil,
    claim_link_default_notifier: nil,
    claim_link_notifiers_current_user_disabled: nil,
    claim_link_current_market_value_enabled: nil,
    claim_link_notifiers: [],
    open_link_email_template: nil,
    connect_favorite_product_groups: nil,
    connect_manual_object_depreciation: nil,
    connect_use_ai_bot: nil,
    connect_news: nil,
    connect_survey: nil,
    white_label_mode: nil,
    settlement_recipients: [],
    dialogue_current_market_value_enabled: nil,
    post_message_to_iframe: nil,
    enabled_item_tags: [],
    printout_languages: nil,
    max_concurrent_connect_logins: nil,
    force_connect_logout_session_hours: nil,
    inactive_connect_session_timeout_hours: nil,
    freemium: nil,
    valuation_parameters: nil,
    single_sign_on: nil
  },
  action: nil,
  hidden: [{"_persistent_id", "0"}],
  params: %{
    "_persistent_id" => "0",
    "_unused_force_connect_logout_session_hours" => "",
    "_unused_freemium" => "",
    "_unused_max_concurrent_connect_logins" => "",
    "force_connect_logout_session_hours" => "",
    "freemium" => "false",
    "inactive_connect_session_timeout_hours" => "-1",
    "max_concurrent_connect_logins" => "",
    "single_sign_on" => %{
      "_persistent_id" => "0",
      "_unused_connected_domains" => "",
      "_unused_type" => "",
      "_unused_version" => "",
      "connected_domains" => "",
      "parameters" => %{
        "_persistent_id" => "0",
        "_unused_button_text" => "",
        "_unused_idp" => "",
        "button_text" => "",
        "idp" => ""
      },
      "type" => "saml",
      "version" => ""
    },
    "valuation_parameters" => %{
      "_persistent_id" => "0",
      "_unused_all_refurbished_stores" => "",
      "_unused_preferred_store_price" => "",
      "all_refurbished_stores" => "false",
      "preferred_store_price" => "median"
    }
  },
  errors: [],
  options: [multipart: false],
  index: 0
}

inactive_connect_session_timeout_hours:

%Phoenix.HTML.FormField{
  id: "company-form_company_settings_0_inactive_connect_session_timeout_hours",
  name: "form[company_settings][inactive_connect_session_timeout_hours]",
  errors: [],
  field: :inactive_connect_session_timeout_hours,
  value: -1
  form: %Phoenix.HTML.Form{
    source: #Ecto.Changeset<
      action: nil,
      changes: %{
        freemium: false,
        valuation_parameters: #Ecto.Changeset<
          action: :insert,
          changes: %{
            preferred_store_price: "median",
            all_refurbished_stores: false
          },
          errors: [],
          data: #Runar.CompanySettings.ValuationParameters<>,
          valid?: true,
          ...
        >,
        single_sign_on: #Ecto.Changeset<
          action: :insert,
          changes: %{
            type: "saml",
            parameters: #Ecto.Changeset<action: :insert, changes: %{},
             errors: [], data: #Runar.CompanySettings.SingleSignOnParams<>,
             valid?: true, ...>
          },
          errors: [],
          data: #Runar.CompanySettings.SingleSignOn<>,
          valid?: true,
          ...
        >,
        inactive_connect_session_timeout_hours: -1
      },
      errors: [
        inactive_connect_session_timeout_hours: {"must be greater than %{number}",
         [validation: :number, kind: :greater_than, number: 0]}
      ],
      data: #Runar.CompanySettings<>,
      valid?: false,
      ...
    >,
    impl: Phoenix.HTML.FormData.Ecto.Changeset,
    id: "company-form_company_settings_0",
    name: "form[company_settings]",
    data: %Runar.CompanySettings{
      claim_link_ai_group_suggestion: nil,
      claim_link_default_expiration: nil,
      claim_link_direct_enabled: nil,
      claim_link_disabled_email_notifications: nil,
      claim_link_enabled: nil,
      claim_link_default_notifier: nil,
      claim_link_notifiers_current_user_disabled: nil,
      claim_link_current_market_value_enabled: nil,
      claim_link_notifiers: [],
      open_link_email_template: nil,
      connect_favorite_product_groups: nil,
      connect_manual_object_depreciation: nil,
      connect_use_ai_bot: nil,
      connect_news: nil,
      connect_survey: nil,
      white_label_mode: nil,
      settlement_recipients: [],
      dialogue_current_market_value_enabled: nil,
      post_message_to_iframe: nil,
      enabled_item_tags: [],
      printout_languages: nil,
      max_concurrent_connect_logins: nil,
      force_connect_logout_session_hours: nil,
      inactive_connect_session_timeout_hours: nil,
      freemium: nil,
      valuation_parameters: nil,
      single_sign_on: nil
    },
    action: nil,
    hidden: [{"_persistent_id", "0"}],
    params: %{
      "_persistent_id" => "0",
      "_unused_force_connect_logout_session_hours" => "",
      "_unused_freemium" => "",
      "_unused_max_concurrent_connect_logins" => "",
      "force_connect_logout_session_hours" => "",
      "freemium" => "false",
      "inactive_connect_session_timeout_hours" => "-1",
      "max_concurrent_connect_logins" => "",
      "single_sign_on" => %{
        "_persistent_id" => "0",
        "_unused_connected_domains" => "",
        "_unused_type" => "",
        "_unused_version" => "",
        "connected_domains" => "",
        "parameters" => %{
          "_persistent_id" => "0",
          "_unused_button_text" => "",
          "_unused_idp" => "",
          "button_text" => "",
          "idp" => ""
        },
        "type" => "saml",
        "version" => ""
      },
      "valuation_parameters" => %{
        "_persistent_id" => "0",
        "_unused_all_refurbished_stores" => "",
        "_unused_preferred_store_price" => "",
        "all_refurbished_stores" => "false",
        "preferred_store_price" => "median"
      }
    },
    errors: [],
    options: [multipart: false],
    index: 0
  },
}

[josevalim]

Can you please file a report in the LiveView repository and include a single file application that reproduces the error? Thank you.

[honungsburk]

There is quite a bit of boilerplate to make an example but all the interesting parts are in a single file: https://github.com/honungsburk/phoenix_nested_form_validation

[honungsburk]

I found the single file template. I'll create another repo using that.

[honungsburk]

https://github.com/honungsburk/phoenix_single_file_nested_form_validation

I get this error when I just ran the template with elixir main.exs:

** (ErlangError) Erlang error: :enoent
    (elixir 1.17.3) lib/system.ex:1114: System.cmd("npm", ["install"], [cd: "/Users/frankhampusweslien/Library/Caches/mix/installs/elixir-1.17.3-erts-15.1.1/28114fb80ebc96d816737c5c55048e3c/deps/phoenix_live_view/lib/.././assets", into: %IO.Stream{device: :standard_io, raw: true, line_or_bytes: :line}])
    main.exs:19: (file)

I'll create a reproduction if you can tell me what I need to do to fix the error.

[SteffenDE]

Hi @honungsburk,

in order to always use the latest JS assets, the single file scripts tries to build them and therefore fetch the dependencies using npm. So you either need nodejs on your system or remove those lines from the script. Currently the included assets should work fine as well.

[honungsburk]

Fixed! phoenixframework/phoenix_live_view#3493

[SteffenDE]

Closing in favor of phoenixframework/phoenix_live_view#3493.