0
votes

I'm building out a view to list/edit/destroy users within the admin namespace, using LiveView (new to Phoenix Elixir). I cannot for some reason, use the method list_users, which is defined in the admin.ex context file. How do I gain access to and use this method in the index.html.heex file, I have to iterate over the users within the table?

Error

function StorefrontApi.Admin.User.list_users/2 is undefined or private

Folder structure below

/lib/storefront_api
/storefront_api/accounts/accounts.ex # normal accounts
/storefront_api/admin/user.ex # admin accounts
/storefront_api/admin.ex # admin context

admin.ex

defmodule StorefrontApi.Admin do
  @moduledoc """
  The Admin context.
  """

  import Ecto.Query, warn: false
  alias StorefrontApi.Repo

  alias StorefrontApi.Admin.{User, UserToken, UserNotifier}

  ## Database getters

  @doc """
  Gets a user by email.

  ## Examples

      iex> get_user_by_email("[email protected]")
      %User{}

      iex> get_user_by_email("[email protected]")
      nil

  """
  def get_user_by_email(email) when is_binary(email) do
    Repo.get_by(User, email: email)
  end

  @doc """
  Gets a user by email and password.

  ## Examples

      iex> get_user_by_email_and_password("[email protected]", "correct_password")
      %User{}

      iex> get_user_by_email_and_password("[email protected]", "invalid_password")
      nil

  """
  def get_user_by_email_and_password(email, password)
      when is_binary(email) and is_binary(password) do
    user = Repo.get_by(User, email: email)
    if User.valid_password?(user, password), do: user
  end

  @doc """
  Gets a single user.

  Raises `Ecto.NoResultsError` if the User does not exist.

  ## Examples

      iex> get_user!(123)
      %User{}

      iex> get_user!(456)
      ** (Ecto.NoResultsError)

  """
  def get_user!(id), do: Repo.get!(User, id)

  ## User registration

  @doc """
  Registers a user.

  ## Examples

      iex> register_user(%{field: value})
      {:ok, %User{}}

      iex> register_user(%{field: bad_value})
      {:error, %Ecto.Changeset{}}

  """
  def register_user(attrs) do
    %User{}
    |> User.registration_changeset(attrs)
    |> Repo.insert()
  end

  @doc """
  Returns an `%Ecto.Changeset{}` for tracking user changes.

  ## Examples

      iex> change_user_registration(user)
      %Ecto.Changeset{data: %User{}}

  """
  def change_user_registration(%User{} = user, attrs \\ %{}) do
    User.registration_changeset(user, attrs, hash_password: false)
  end

  ## Settings

  @doc """
  Returns an `%Ecto.Changeset{}` for changing the user email.

  ## Examples

      iex> change_user_email(user)
      %Ecto.Changeset{data: %User{}}

  """
  def change_user_email(user, attrs \\ %{}) do
    User.email_changeset(user, attrs)
  end

  @doc """
  Emulates that the email will change without actually changing
  it in the database.

  ## Examples

      iex> apply_user_email(user, "valid password", %{email: ...})
      {:ok, %User{}}

      iex> apply_user_email(user, "invalid password", %{email: ...})
      {:error, %Ecto.Changeset{}}

  """
  def apply_user_email(user, password, attrs) do
    user
    |> User.email_changeset(attrs)
    |> User.validate_current_password(password)
    |> Ecto.Changeset.apply_action(:update)
  end

  @doc """
  Updates the user email using the given token.

  If the token matches, the user email is updated and the token is deleted.
  The confirmed_at date is also updated to the current time.
  """
  def update_user_email(user, token) do
    context = "change:#{user.email}"

    with {:ok, query} <- UserToken.verify_change_email_token_query(token, context),
         %UserToken{sent_to: email} <- Repo.one(query),
         {:ok, _} <- Repo.transaction(user_email_multi(user, email, context)) do
      :ok
    else
      _ -> :error
    end
  end

  defp user_email_multi(user, email, context) do
    changeset =
      user
      |> User.email_changeset(%{email: email})
      |> User.confirm_changeset()

    Ecto.Multi.new()
    |> Ecto.Multi.update(:user, changeset)
    |> Ecto.Multi.delete_all(:tokens, UserToken.user_and_contexts_query(user, [context]))
  end

  @doc """
  Delivers the update email instructions to the given user.

  ## Examples

      iex> deliver_update_email_instructions(user, current_email, &Routes.user_update_email_url(conn, :edit, &1))
      {:ok, %{to: ..., body: ...}}

  """
  def deliver_update_email_instructions(%User{} = user, current_email, update_email_url_fun)
      when is_function(update_email_url_fun, 1) do
    {encoded_token, user_token} = UserToken.build_email_token(user, "change:#{current_email}")

    Repo.insert!(user_token)
    UserNotifier.deliver_update_email_instructions(user, update_email_url_fun.(encoded_token))
  end

  @doc """
  Returns an `%Ecto.Changeset{}` for changing the user password.

  ## Examples

      iex> change_user_password(user)
      %Ecto.Changeset{data: %User{}}

  """
  def change_user_password(user, attrs \\ %{}) do
    User.password_changeset(user, attrs, hash_password: false)
  end

  @doc """
  Updates the user password.

  ## Examples

      iex> update_user_password(user, "valid password", %{password: ...})
      {:ok, %User{}}

      iex> update_user_password(user, "invalid password", %{password: ...})
      {:error, %Ecto.Changeset{}}

  """
  def update_user_password(user, password, attrs) do
    changeset =
      user
      |> User.password_changeset(attrs)
      |> User.validate_current_password(password)

    Ecto.Multi.new()
    |> Ecto.Multi.update(:user, changeset)
    |> Ecto.Multi.delete_all(:tokens, UserToken.user_and_contexts_query(user, :all))
    |> Repo.transaction()
    |> case do
      {:ok, %{user: user}} -> {:ok, user}
      {:error, :user, changeset, _} -> {:error, changeset}
    end
  end

  ## Session

  @doc """
  Generates a session token.
  """
  def generate_user_session_token(user) do
    {token, user_token} = UserToken.build_session_token(user)
    Repo.insert!(user_token)
    token
  end

  @doc """
  Gets the user with the given signed token.
  """
  def get_user_by_session_token(token) do
    {:ok, query} = UserToken.verify_session_token_query(token)
    Repo.one(query)
  end

  @doc """
  Deletes the signed token with the given context.
  """
  def delete_session_token(token) do
    Repo.delete_all(UserToken.token_and_context_query(token, "session"))
    :ok
  end

  ## Confirmation

  @doc """
  Delivers the confirmation email instructions to the given user.

  ## Examples

      iex> deliver_user_confirmation_instructions(user, &Routes.user_confirmation_url(conn, :edit, &1))
      {:ok, %{to: ..., body: ...}}

      iex> deliver_user_confirmation_instructions(confirmed_user, &Routes.user_confirmation_url(conn, :edit, &1))
      {:error, :already_confirmed}

  """
  def deliver_user_confirmation_instructions(%User{} = user, confirmation_url_fun)
      when is_function(confirmation_url_fun, 1) do
    if user.confirmed_at do
      {:error, :already_confirmed}
    else
      {encoded_token, user_token} = UserToken.build_email_token(user, "confirm")
      Repo.insert!(user_token)
      UserNotifier.deliver_confirmation_instructions(user, confirmation_url_fun.(encoded_token))
    end
  end

  @doc """
  Confirms a user by the given token.

  If the token matches, the user account is marked as confirmed
  and the token is deleted.
  """
  def confirm_user(token) do
    with {:ok, query} <- UserToken.verify_email_token_query(token, "confirm"),
         %User{} = user <- Repo.one(query),
         {:ok, %{user: user}} <- Repo.transaction(confirm_user_multi(user)) do
      {:ok, user}
    else
      _ -> :error
    end
  end

  defp confirm_user_multi(user) do
    Ecto.Multi.new()
    |> Ecto.Multi.update(:user, User.confirm_changeset(user))
    |> Ecto.Multi.delete_all(:tokens, UserToken.user_and_contexts_query(user, ["confirm"]))
  end

  ## Reset password

  @doc """
  Delivers the reset password email to the given user.

  ## Examples

      iex> deliver_user_reset_password_instructions(user, &Routes.user_reset_password_url(conn, :edit, &1))
      {:ok, %{to: ..., body: ...}}

  """
  def deliver_user_reset_password_instructions(%User{} = user, reset_password_url_fun)
      when is_function(reset_password_url_fun, 1) do
    {encoded_token, user_token} = UserToken.build_email_token(user, "reset_password")
    Repo.insert!(user_token)
    UserNotifier.deliver_reset_password_instructions(user, reset_password_url_fun.(encoded_token))
  end

  @doc """
  Gets the user by reset password token.

  ## Examples

      iex> get_user_by_reset_password_token("validtoken")
      %User{}

      iex> get_user_by_reset_password_token("invalidtoken")
      nil

  """
  def get_user_by_reset_password_token(token) do
    with {:ok, query} <- UserToken.verify_email_token_query(token, "reset_password"),
         %User{} = user <- Repo.one(query) do
      user
    else
      _ -> nil
    end
  end

  @doc """
  Resets the user password.

  ## Examples

      iex> reset_user_password(user, %{password: "new long password", password_confirmation: "new long password"})
      {:ok, %User{}}

      iex> reset_user_password(user, %{password: "valid", password_confirmation: "not the same"})
      {:error, %Ecto.Changeset{}}

  """
  def reset_user_password(user, attrs) do
    Ecto.Multi.new()
    |> Ecto.Multi.update(:user, User.password_changeset(user, attrs))
    |> Ecto.Multi.delete_all(:tokens, UserToken.user_and_contexts_query(user, :all))
    |> Repo.transaction()
    |> case do
      {:ok, %{user: user}} -> {:ok, user}
      {:error, :user, changeset, _} -> {:error, changeset}
    end
  end

  @doc """
  List admin users
  """
  def list_users(current_page, per_page) do
    Repo.all(
      from u in User,
      order_by: [asc: u.id],
      offset: ^((current_page - 1) * per_page),
      limit: ^per_page
    )
  end
end

live/users/index.ex

defmodule StorefrontApiWeb.UserLive.Index do
  use StorefrontApiWeb, :live_view

  alias StorefrontApi.Admin.{User}
  alias StorefrontApiWeb.Router.Helpers, as: Routes

  def mount(_params, _session, socket) do
    if connected?(socket), do: User.subscribe()
    {:ok, assign(socket, page: 1, per_page: 5)}
  end

  def handle_params(params, _url, socket) do
    {page, ""} = Integer.parse(params["page"] || "1")
    {:noreply, socket |> assign(page: page) |> fetch()}
  end

  defp fetch(socket) do
    %{page: page, per_page: per_page} = socket.assigns
    users = User.list_users(page, per_page)
    assign(socket, users: users, page_title: "Listing Admin Users – Page #{page}")
  end

  def handle_info({User, [:user | _], _}, socket) do
    {:noreply, fetch(socket)}
  end

  def handle_event("keydown", %{"key" => "ArrowLeft"}, socket) do
    {:noreply, go_page(socket, socket.assigns.page - 1)}
  end
  def handle_event("keydown", %{"key" => "ArrowRight"}, socket) do
    {:noreply, go_page(socket, socket.assigns.page + 1)}
  end
  def handle_event("keydown", _, socket), do: {:noreply, socket}

  def handle_event("delete_user", %{"id" => id}, socket) do
    user = User.get_user!(id)
    {:ok, _user} = User.delete_user(user)

    {:noreply, socket}
  end

  defp go_page(socket, page) when page > 0 do
    push_patch(socket, to: Routes.user_index_path(socket, :index, page: page))
  end
  defp go_page(socket, _page), do: socket
end
1

1 Answers

0
votes

In your code, list_users/2 is defined in StorefrontApi.Admin, not StorefrontApi.Admin.User.

This seems like code from the Phoenix generators. Admin is the context (where the actual CRUD functions live), Admin.User is just a schema, which is different from the "model" approach from traditional MVC frameworks. The structure and philosophy of Phoenix contexts are explained here.