KeyError at /posts键:主题未在：%{/posts：#Ecto.Changeset中找到

Question

我正在向表单中添加更多字段：

我把它们添加到post.ex中

field :name_of_gallery, :string
field :future_plans_title, :string

将它们添加到stories.ex中的变更集中：

     defp post_changeset(%Post{} = post, attrs \\ %{}) do
      post
      |> cast(attrs, [:title, :body, :user_id, :published, :original_post_id, :topic_id, :plan, :done_so_far_one, :done_so_far_two, :done_so_far_three, :done_so_far_one_title, :done_so_far_two_title, :done_so_far_three_title, :name_of_gallery, :future_plans_title])
      |> cast_attachments(attrs, [:project_pic])
      |> validate_required([:title, :body, :user_id, :topic_id, :plan, :done_so_far_one, :done_so_far_two, :done_so_far_three,  :done_so_far_one_title, :done_so_far_two_title, :done_so_far_three_title, :project_pic, :name_of_gallery, :future_plans_title]) 
  end

创建了两个迁移文件(这里只显示了一个)：

defmodule Citybuilder.Repo.Migrations.AddNameOfGalleryToFields do
  use Ecto.Migration

  def change do
  alter table (:stories_posts) do
    add :future_plans_title, :string

  end
end
end 

我跑了：

mix ecto.drop
mix ecto.setup
mix ecto.migrate
mix run priv/repo/seeds.exs

..。不止一次。

当我检查psql时，它们在postgres：

name_of_gallery _~_

*

用户不能再保存表单了。保存用户表单(在此之前有效)返回：

KeyError at POST /posts
key :topics not found in: %{changeset: #Ecto.Changeset<action: :insert, changes: %{body: 

在网上有一个错误：

  <%= select f, :topic_id, topic_select(@conn.assigns.topics), class: "form-control form-control-topic", placeholder: "Select topic." %>

我有一个主题选择菜单，但这从来没有引起问题。

*

以下是整个错误消息(请求)：

key :topics not found in: %{changeset: #Ecto.Changeset<action: :insert, changes: %{body: "My Project Summary", done_so_far_one: "Done So Far One Body", done_so_far_one_title: "Done So Far One Title", done_so_far_three: "Random Text to Test Form", done_so_far_three_title: "Random Text to Test Form", done_so_far_two: "Random Text to Test Form", done_so_far_two_title: "Random Text to Test Form", name_of_gallery: "Random Text to Test Form", plan: "My Project Plan", project_pic: %{file_name: "person-woman-park-music (1).jpg", updated_at: #Ecto.DateTime<2017-08-08 13:11:46>}, title: "My Project Title", topic_id: 1, user_id: 2}, errors: [future_plans_title: {"can't be blank", [validation: :required]}], data: #Citybuilder.Stories.Post<>, valid?: false>, layout: {Citybuilder.Web.LayoutView, "app.html"}, user: %Citybuilder.Auths.User{__meta__: #Ecto.Schema.Metadata<:loaded, "auths_users">, admin: false, encrypted_password: "$2b$12$MvDVJo01scAyrrBtnT1dpulbuj9uwDnS2ZezFeUhmzol7mJXRBYa6", id: 2, inserted_at: ~N[2017-08-08 12:20:13.948747], moderator: false, password: nil, password_confirmation: nil, updated_at: ~N[2017-08-08 12:20:13.970885], username: "jarvis"}}

下面是post和新功能的控制器代码：

def new(conn, _params) do
    default_topic = Stories.get_topic!(@default_topic)
    changeset = Stories.change_post(
      %Citybuilder.Stories.Post{},
      %{topic_id: default_topic.id}
    )
    render(conn, "new.html", changeset: changeset)
  end

  def create(conn, %{"post" => post_params}) do
    case Stories.create_post(post_params, conn.assigns.user) do
      {:ok, post} ->
        conn
        # |> put_flash(:info, "Post created! ヽ(´▽`)/")
        |> redirect(to: post_path(conn, :show, post))
      {:error, %Ecto.Changeset{} = changeset} ->
        render(conn, "new.html", changeset: changeset)
    end
  end

Answer 1

更改了这一行：

 plug :set_topics when action in [:index, :new, :edit, :update, :fork]

对此：

plug :set_topics when action in [:index, :new, :edit, :create, :update, :fork]

添加了创建函数。表单现在通过了编译器，但是仍然存在一些验证错误。

*

若要修复表单验证：

我有一些领域在我的改变：

  defp post_changeset(%Post{} = post, attrs \\ %{}) do
 post
    |> cast(attrs, [:title, :body, :user_id, :published, :original_post_id, :topic_id, :plan, :done_so_far_one, :done_so_far_two, :done_so_far_three, :done_so_far_one_title, :done_so_far_two_title, :done_so_far_three_title, :name_of_gallery, :future_plans_title])
    |> cast_attachments(attrs, [:project_pic])
    |> validate_required([:title, :body, :user_id, :topic_id, :plan, :done_so_far_one, :done_so_far_two, :done_so_far_three,  :done_so_far_one_title, :done_so_far_two_title, :done_so_far_three_title, :project_pic, :name_of_gallery, :future_plans_title])

这在form.html.eex中不存在。验证表单时，菲尼克斯/Ecto期望所有字段。缺少的字段返回未经验证的表单的闪存错误。