Changeset/1 undefined

Phoenix Forum Questions / Help
,
1

I’m trying to create a contact email form with the context of Contact >Emails, however I’m running into changeset problems and I’ve been going round in circles trying to solve it.

The changeset is within my email.ex file:

defmodule Iotc.Contact.Email do
  use Ecto.Schema
  import Ecto.Changeset
  alias Iotc.Contact.Email


  schema "contact_emails" do
    field :email, :string
    field :event, :string
    field :message, :string
    field :name, :string

    timestamps()
  end


  def changeset(%Email{} = email, attrs) do
    email
    |> cast(attrs, [:name, :email, :message, :event])
    |> validate_required([:name, :email, :message])
  end
end

And my email_controller.ex has the following:

defmodule Iotc.Web.EmailController do
  use Iotc.Web, :controller
  alias Iotc.Contact

  def index(conn, _params) do
    changeset = Contact.Email.changeset(%Contact.Email{})
    emails = Contact.list_emails()
    render(conn, "index.html", emails: emails, changeset: changeset)
  end

  def new(conn, _params) do
    changeset = Contact.changeset(%Contact.Email{})
    render(conn, "new.html", changeset: changeset)
  end

  def create(conn, %{"email" => email_params}) do
    changeset = Contact.changeset(%Iotc.Contact.Email{}, email_params)
    case Contact.create_email(changeset) do
      {:ok, email} ->
        conn
        |> put_flash(:info, "Email sent")
        |> redirect(to: email_path(conn, :index))
      {:error, changeset} ->
        conn
        |> put_flash(:error, "Something went wrong")
        |> render("index.html", changeset: changeset)
    end
  end

That current set up gives me function Iotc.Contact.Email.changeset/1 is undefined or private so I’ve tried changeset = Contact.changeset(%Email{}) as well, but this gives me another error of ib/iotc/web/controllers/email_controller.ex:6: Email.__struct__/1 is undefined, cannot expand struct Email.

This isp probably so simply, but I’ve now gone blind.

1 Like
2

Your changeset is defined inside Contact.Email, not Contact

3

The error function Iotc.Contact.Email.changeset/1 is undefined or private say why the reason of you error, you had define a function with arity 2, on call function you give only one param, you call should be:

def new(conn, params) do
changeset = Contact.changeset(%Contact.Email{}, params)
render(conn, “new.html”, changeset: changeset)
end

or you can change the function signature on Iotc.Contact.Email to include default value of attrs param like this:

> def changeset(%Email{} = email, attrs \\ %{}) do
>     email
>     |> cast(attrs, [:name, :email, :message, :event])
>     |> validate_required([:name, :email, :message])
>   end
1 Like
4

Yes. So how do I call that correctly from my controller? Doesn’t changeset = Contact.Email.changeset already do that. Or can I change the alias to Iotc.Contact.Email?

5

As @Cleidiano mentionned, it’s an arity problem, You don’t have changeset/1, you have changeset/2

You have defined…

def changeset(%Email{} = email, attrs) do … end

but You are using…

changeset = Contact.Email.changeset(%Contact.Email{})

6

Thanks.

However, if I use:

  def new(conn, params) do
    changeset = Contact.changeset(%Contact.Email{}, params)
    render(conn, "new.html", changeset: changeset)
  end

As per @Cleidiano suggestion, I just get function Iotc.Contact.changeset/2 is undefined or private.

As you might be able to tell, I’m new to this! :wink:

I also just generated the code via mix phx.gen.html so I guess I don’t understand the real workings of what needs to be changed from what Phoenix generates.

7

Because You must use Contact.Email.changeset…

Using phx generator means You are using phoenix 1.3

So there is this context boundary :slight_smile:

and Contact is your boundary, where You should define all the functions for the contact boundary.

That is why they use Contact.changeset. You should have a look at the Contact.ex file and see what is inside

8

Makes sense.

We might be getting somewhere, as I now get a new error: assign @changeset not available in eex template.

My form looks like:

<%= form_for @changeset, email_path(@conn, :create), fn f -> %>

9

That was an issue with my render tag.

Sorted.

Thanks for the advice.

10

You have a lot of Contact.changeset(%Contact.Email{}) in your controller

In particular in the new action.

I guess if You have a form, you are either doing new or edit

BTW I don’t see the need to pass a changeset in the index action.

I don’t use generators, is your controller generated automaticaly?

11

Yeah the controller was generated automatically. I’m going to go through and clean it up as you’re right, there’s a lot in there I don’t need.