adds post liveview and schema

Author: elixirprogrammer

lib/reddit/category/community.ex

@@ -4,6 +4,7 @@ defmodule Reddit.Category.Community do
 
   alias Reddit.Users.User
   alias Reddit.Community.Subscription
+  alias Reddit.Community.Post
 
   schema "communities" do
     field :name, :string
@@ -12,6 +13,7 @@ defmodule Reddit.Category.Community do
     field :members, :integer, default: 0
     belongs_to :user, User
     has_many :subscriptions, Subscription
+    has_many :posts, Post
 
     timestamps()
   end

lib/reddit/community.ex

@@ -0,0 +1,104 @@
+defmodule Reddit.Community do
+  @moduledoc """
+  The Community context.
+  """
+
+  import Ecto.Query, warn: false
+  alias Reddit.Repo
+
+  alias Reddit.Community.Post
+
+  @doc """
+  Returns the list of posts.
+
+  ## Examples
+
+      iex> list_posts()
+      [%Post{}, ...]
+
+  """
+  def list_posts do
+    Repo.all(Post)
+  end
+
+  @doc """
+  Gets a single post.
+
+  Raises `Ecto.NoResultsError` if the Post does not exist.
+
+  ## Examples
+
+      iex> get_post!(123)
+      %Post{}
+
+      iex> get_post!(456)
+      ** (Ecto.NoResultsError)
+
+  """
+  def get_post!(id), do: Repo.get!(Post, id)
+
+  @doc """
+  Creates a post.
+
+  ## Examples
+
+      iex> create_post(%{field: value})
+      {:ok, %Post{}}
+
+      iex> create_post(%{field: bad_value})
+      {:error, %Ecto.Changeset{}}
+
+  """
+  def create_post(attrs \\ %{}) do
+    %Post{}
+    |> Post.changeset(attrs)
+    |> Repo.insert()
+  end
+
+  @doc """
+  Updates a post.
+
+  ## Examples
+
+      iex> update_post(post, %{field: new_value})
+      {:ok, %Post{}}
+
+      iex> update_post(post, %{field: bad_value})
+      {:error, %Ecto.Changeset{}}
+
+  """
+  def update_post(%Post{} = post, attrs) do
+    post
+    |> Post.changeset(attrs)
+    |> Repo.update()
+  end
+
+  @doc """
+  Deletes a post.
+
+  ## Examples
+
+      iex> delete_post(post)
+      {:ok, %Post{}}
+
+      iex> delete_post(post)
+      {:error, %Ecto.Changeset{}}
+
+  """
+  def delete_post(%Post{} = post) do
+    Repo.delete(post)
+  end
+
+  @doc """
+  Returns an `%Ecto.Changeset{}` for tracking post changes.
+
+  ## Examples
+
+      iex> change_post(post)
+      %Ecto.Changeset{data: %Post{}}
+
+  """
+  def change_post(%Post{} = post, attrs \\ %{}) do
+    Post.changeset(post, attrs)
+  end
+end

lib/reddit/community/post.ex

@@ -0,0 +1,26 @@
+defmodule Reddit.Community.Post do
+  use Ecto.Schema
+  import Ecto.Changeset
+
+  alias Reddit.Category.Community
+  alias Reddit.Users.User
+
+  schema "posts" do
+    field :body, :string
+    field :title, :string
+    field :upvote, :integer, default: 0
+    field :downvote, :integer, default: 0
+    field :comments, :integer, default: 0
+    belongs_to :community, Community
+    belongs_to :user, User
+
+    timestamps()
+  end
+
+  @doc false
+  def changeset(post, attrs) do
+    post
+    |> cast(attrs, [:title, :body, :upvote, :downvote, :comments])
+    |> validate_required([:title, :body])
+  end
+end

lib/reddit/users/user.ex

@@ -11,6 +11,7 @@ defmodule Reddit.Users.User do
   alias Reddit.Repo
   alias Reddit.Category.Community
   alias Reddit.Community.Subscription
+  alias Reddit.Community.Post
 
   schema "users" do
     pow_user_fields()
@@ -21,6 +22,7 @@ defmodule Reddit.Users.User do
     field :karma, :integer, default: 0
     has_many :communities, Community
     has_many :subscriptions, Subscription
+    has_many :posts, Post
 
     timestamps()
   end

lib/reddit_web.ex

@@ -94,6 +94,7 @@ defmodule RedditWeb do
 
       # Import LiveView helpers (live_render, live_component, live_patch, etc)
       import Phoenix.LiveView.Helpers
+      import RedditWeb.LiveHelpers
 
       # Import basic rendering functionality (render, render_layout, etc)
       import Phoenix.View

lib/reddit_web/live/live_helpers.ex

@@ -0,0 +1,23 @@
+defmodule RedditWeb.LiveHelpers do
+  import Phoenix.LiveView.Helpers
+
+  @doc """
+  Renders a component inside the `RedditWeb.ModalComponent` component.
+
+  The rendered modal receives a `:return_to` option to properly update
+  the URL when the modal is closed.
+
+  ## Examples
+
+      <%= live_modal @socket, RedditWeb.PostLive.FormComponent,
+        id: @post.id || :new,
+        action: @live_action,
+        post: @post,
+        return_to: Routes.post_index_path(@socket, :index) %>
+  """
+  def live_modal(socket, component, opts) do
+    path = Keyword.fetch!(opts, :return_to)
+    modal_opts = [id: :modal, return_to: path, component: component, opts: opts]
+    live_component(socket, RedditWeb.ModalComponent, modal_opts)
+  end
+end

lib/reddit_web/live/modal_component.ex

@@ -0,0 +1,26 @@
+defmodule RedditWeb.ModalComponent do
+  use RedditWeb, :live_component
+
+  @impl true
+  def render(assigns) do
+    ~L"""
+    <div id="<%= @id %>" class="phx-modal"
+      phx-capture-click="close"
+      phx-window-keydown="close"
+      phx-key="escape"
+      phx-target="#<%= @id %>"
+      phx-page-loading>
+
+      <div class="phx-modal-content">
+        <%= live_patch raw("&times;"), to: @return_to, class: "phx-modal-close" %>
+        <%= live_component @socket, @component, @opts %>
+      </div>
+    </div>
+    """
+  end
+
+  @impl true
+  def handle_event("close", _, socket) do
+    {:noreply, push_patch(socket, to: socket.assigns.return_to)}
+  end
+end

lib/reddit_web/live/post_live/form_component.ex

@@ -0,0 +1,55 @@
+defmodule RedditWeb.PostLive.FormComponent do
+  use RedditWeb, :live_component
+
+  alias Reddit.Community
+
+  @impl true
+  def update(%{post: post} = assigns, socket) do
+    changeset = Community.change_post(post)
+
+    {:ok,
+     socket
+     |> assign(assigns)
+     |> assign(:changeset, changeset)}
+  end
+
+  @impl true
+  def handle_event("validate", %{"post" => post_params}, socket) do
+    changeset =
+      socket.assigns.post
+      |> Community.change_post(post_params)
+      |> Map.put(:action, :validate)
+
+    {:noreply, assign(socket, :changeset, changeset)}
+  end
+
+  def handle_event("save", %{"post" => post_params}, socket) do
+    save_post(socket, socket.assigns.action, post_params)
+  end
+
+  defp save_post(socket, :edit, post_params) do
+    case Community.update_post(socket.assigns.post, post_params) do
+      {:ok, _post} ->
+        {:noreply,
+         socket
+         |> put_flash(:info, "Post updated successfully")
+         |> push_redirect(to: socket.assigns.return_to)}
+
+      {:error, %Ecto.Changeset{} = changeset} ->
+        {:noreply, assign(socket, :changeset, changeset)}
+    end
+  end
+
+  defp save_post(socket, :new, post_params) do
+    case Community.create_post(post_params) do
+      {:ok, _post} ->
+        {:noreply,
+         socket
+         |> put_flash(:info, "Post created successfully")
+         |> push_redirect(to: socket.assigns.return_to)}
+
+      {:error, %Ecto.Changeset{} = changeset} ->
+        {:noreply, assign(socket, changeset: changeset)}
+    end
+  end
+end

lib/reddit_web/live/post_live/form_component.html.leex

@@ -0,0 +1,18 @@
+<h2><%= @title %></h2>
+
+<%= f = form_for @changeset, "#",
+  id: "post-form",
+  phx_target: @myself,
+  phx_change: "validate",
+  phx_submit: "save" %>
+
+  <%= label f, :title %>
+  <%= text_input f, :title %>
+  <%= error_tag f, :title %>
+
+  <%= label f, :body %>
+  <%= textarea f, :body %>
+  <%= error_tag f, :body %>
+
+  <%= submit "Save", phx_disable_with: "Saving..." %>
+</form>

lib/reddit_web/live/post_live/index.ex

@@ -0,0 +1,46 @@
+defmodule RedditWeb.PostLive.Index do
+  use RedditWeb, :live_view
+
+  alias Reddit.Community
+  alias Reddit.Community.Post
+
+  @impl true
+  def mount(_params, _session, socket) do
+    {:ok, assign(socket, :posts, list_posts())}
+  end
+
+  @impl true
+  def handle_params(params, _url, socket) do
+    {:noreply, apply_action(socket, socket.assigns.live_action, params)}
+  end
+
+  defp apply_action(socket, :edit, %{"id" => id}) do
+    socket
+    |> assign(:page_title, "Edit Post")
+    |> assign(:post, Community.get_post!(id))
+  end
+
+  defp apply_action(socket, :new, _params) do
+    socket
+    |> assign(:page_title, "New Post")
+    |> assign(:post, %Post{})
+  end
+
+  defp apply_action(socket, :index, _params) do
+    socket
+    |> assign(:page_title, "Listing Posts")
+    |> assign(:post, nil)
+  end
+
+  @impl true
+  def handle_event("delete", %{"id" => id}, socket) do
+    post = Community.get_post!(id)
+    {:ok, _} = Community.delete_post(post)
+
+    {:noreply, assign(socket, :posts, list_posts())}
+  end
+
+  defp list_posts do
+    Community.list_posts()
+  end
+end