add topic subscriptions

lib/philomena/topics.ex

@@ -104,35 +104,13 @@ defmodule Philomena.Topics do
 
   alias Philomena.Topics.Subscription
 
-  @doc """
-  Returns the list of topic_subscriptions.
-
-  ## Examples
-
-      iex> list_topic_subscriptions()
-      [%Subscription{}, ...]
-
-  """
-  def list_topic_subscriptions do
-    Repo.all(Subscription)
+  def subscribed?(topic, nil), do: false
+  def subscribed?(topic, user) do
+    Subscription
+    |> where(topic_id: ^topic.id, user_id: ^user.id)
+    |> Repo.exists?()
   end
 
-  @doc """
-  Gets a single subscription.
-
-  Raises `Ecto.NoResultsError` if the Subscription does not exist.
-
-  ## Examples
-
-      iex> get_subscription!(123)
-      %Subscription{}
-
-      iex> get_subscription!(456)
-      ** (Ecto.NoResultsError)
-
-  """
-  def get_subscription!(id), do: Repo.get!(Subscription, id)
-
   @doc """
   Creates a subscription.
 
@@ -145,28 +123,10 @@ defmodule Philomena.Topics do
       {:error, %Ecto.Changeset{}}
 
   """
-  def create_subscription(attrs \\ %{}) do
-    %Subscription{}
-    |> Subscription.changeset(attrs)
-    |> Repo.insert()
-  end
-
-  @doc """
-  Updates a subscription.
-
-  ## Examples
-
-      iex> update_subscription(subscription, %{field: new_value})
-      {:ok, %Subscription{}}
-
-      iex> update_subscription(subscription, %{field: bad_value})
-      {:error, %Ecto.Changeset{}}
-
-  """
-  def update_subscription(%Subscription{} = subscription, attrs) do
-    subscription
-    |> Subscription.changeset(attrs)
-    |> Repo.update()
+  def create_subscription(topic, user) do
+    %Subscription{topic_id: topic.id, user_id: user.id}
+    |> Subscription.changeset(%{})
+    |> Repo.insert(on_conflict: :nothing)
   end
 
   @doc """
@@ -181,20 +141,8 @@ defmodule Philomena.Topics do
       {:error, %Ecto.Changeset{}}
 
   """
-  def delete_subscription(%Subscription{} = subscription) do
-    Repo.delete(subscription)
-  end
-
-  @doc """
-  Returns an `%Ecto.Changeset{}` for tracking subscription changes.
-
-  ## Examples
-
-      iex> change_subscription(subscription)
-      %Ecto.Changeset{source: %Subscription{}}
-
-  """
-  def change_subscription(%Subscription{} = subscription) do
-    Subscription.changeset(subscription, %{})
+  def delete_subscription(topic, user) do
+    %Subscription{topic_id: topic.id, user_id: user.id}
+    |> Repo.delete()
   end
 end

lib/philomena_web/controllers/topic/subscription_controller.ex

@@ -0,0 +1,45 @@
+defmodule PhilomenaWeb.Topic.SubscriptionController do
+  use PhilomenaWeb, :controller
+
+  alias Philomena.{Topics, Topics.Topic, Forums.Forum}
+  alias Philomena.Repo
+  import Ecto.Query
+
+  plug PhilomenaWeb.Plugs.CanaryMapPlug, create: :show, delete: :show
+  plug :load_and_authorize_resource, model: Forum, id_name: "forum_id", id_field: "short_name", persisted: true
+
+  def create(conn, %{"topic_id" => slug}) do
+    topic = load_topic(conn, slug)
+    user = conn.assigns.current_user
+
+    case Topics.create_subscription(topic, user) do
+      {:ok, _subscription} ->
+        render(conn, "_subscription.html", forum: conn.assigns.forum, topic: topic, watching: true, layout: false)
+
+      {:error, _changeset} ->
+        render(conn, "_error.html", layout: false)
+    end
+  end
+
+  def delete(conn, %{"topic_id" => slug}) do
+    topic = load_topic(conn, slug)
+    user = conn.assigns.current_user
+
+    case Topics.delete_subscription(topic, user) do
+      {:ok, _subscription} ->
+        render(conn, "_subscription.html", forum: conn.assigns.forum, topic: topic, watching: false, layout: false)
+
+      {:error, _changeset} ->
+        render(conn, "_error.html", layout: false)
+    end
+  end
+
+  defp load_topic(conn, slug) do
+    forum = conn.assigns.forum
+    topic =
+      Topic
+      |> where(forum_id: ^forum.id, slug: ^slug, hidden_from_users: false)
+      |> preload(:user)
+      |> Repo.one()
+  end
+end

lib/philomena_web/controllers/topic_controller.ex

@@ -1,7 +1,7 @@
 defmodule PhilomenaWeb.TopicController do
   use PhilomenaWeb, :controller
 
-  alias Philomena.{Forums.Forum, Topics.Topic, Posts.Post, Textile.Renderer}
+  alias Philomena.{Forums.Forum, Topics, Topics.Topic, Posts.Post, Textile.Renderer}
   alias Philomena.Repo
   import Ecto.Query
 
@@ -51,6 +51,9 @@ defmodule PhilomenaWeb.TopicController do
         total_pages: div(topic.post_count + 25 - 1, 25)
       }
 
-    render(conn, "show.html", posts: posts)
+    watching =
+      Topics.subscribed?(topic, conn.assigns.current_user)
+
+    render(conn, "show.html", posts: posts, watching: watching)
   end
 end

lib/philomena_web/router.ex

@@ -60,6 +60,12 @@ defmodule PhilomenaWeb.Router do
       resources "/hide", Image.HideController, only: [:create, :delete], singleton: true
       resources "/subscription", Image.SubscriptionController, only: [:create, :delete], singleton: true
     end
+
+    resources "/forums", ForumController, only: [] do
+      resources "/topics", TopicController, only: [] do
+        resources "/subscription", Topic.SubscriptionController, only: [:create, :delete], singleton: true
+      end
+    end
   end
 
   scope "/", PhilomenaWeb do

lib/philomena_web/templates/topic/show.html.slime

@@ -24,10 +24,7 @@ h1 = @topic.title
     .flex--fixed.block__header__item
       => @topic.post_count - 1
       ' replies
-    /= if current_user
-    /  = subscription_link(@topic, current_user)
-    /- else
-    ' Login to subscribe to responses
+    = render PhilomenaWeb.Topic.SubscriptionView, "_subscription.html", forum: @forum, topic: @topic, watching: @watching, conn: @conn
 
 / Display the poll, if any
 /= render partial: 'polls/display', locals: { poll: @topic.poll }

lib/philomena_web/templates/topic/subscription/_subscription.html.slime

@@ -0,0 +1,23 @@
+elixir:
+  watch_path = Routes.forum_topic_subscription_path(@conn, :create, @forum, @topic)
+  watch_class = if @watching, do: "hidden", else: ""
+
+  unwatch_path = Routes.forum_topic_subscription_path(@conn, :delete, @forum, @topic)
+  unwatch_class = if @watching, do: "", else: "hidden"
+
+= if @conn.assigns.current_user do
+  #js-subscription-target
+    a.js-subscription-link href=watch_path class=watch_class data-remote="true" data-method="post"
+      i.fa.fa-bell>
+      span.hide-mobile
+        ' Subscribe
+
+    a.js-subscription-link href=unwatch_path class=unwatch_class data-remote="true" data-method="delete"
+      i.fa.fa-bell-slash>
+      span.hide-mobile
+        ' Unsubscribe
+- else
+    a href=Routes.pow_session_path(@conn, :new)
+      i.fa.fa-bell>
+      span.hide-mobile
+        ' Subscribe

lib/philomena_web/views/topic/subscription_view.ex

@@ -0,0 +1,3 @@
+defmodule PhilomenaWeb.Topic.SubscriptionView do
+  use PhilomenaWeb, :view
+end