Phoenix alter model

What is the correct way to alter a ecto model in Phoenix?

So far I've created a Post model which contains a title and a content string field. I added the resource to the router to create and view the Posts.
Now I would like to add a author field to my model. What I did until now is the following:

I created a migration with

mix ecto.gen.migration add_author_to_post

In the migrationfile I inserted

alter table(:posts) do
  add :author, :string
end

and ran the migration with mix ecto.migrate.
Now the coloumn is visible in the database.
Then I added the fileld to my model file:

schema "posts" do 
  field :title, :string
  field :content, :string
  field :author, :string
  timestamps
end

@required_fields ~w(title content author)
@optional_fields ~w()

But when I visit the page to add a new Post, there is no field to add an author in the html.file. (The new.html.eex file was generated by the mix phoenix.gen.html)

PS: I'm sure this is a basic beginner question. But since the phoenixcommunity is quite small, this question might be usefull for lots of other people

Solution

The template is not based on the current schema defined in your model. It is based on what you pass the mix phoenix.gen.html task.

You will need to update your template to include the author in web/templates/post/form.html.eex

  <div class="form-group">
    <label>Author</label>
    <%= text_input f, :author, class: "form-control" %>
  </div>