Fix items w/o guids getting duplicated on every update

lib/frenzy/item.ex

@@ -82,9 +82,20 @@ defmodule Frenzy.Item do
   @doc false
   def changeset(item, attrs) do
     item
-    |> cast(attrs, [:guid, :title, :url, :creator, :date, :content, :read, :read_date, :tombstone])
-    |> validate_required([:guid, :url, :date, :content, :feed])
-    |> unique_constraint(:items_feed_guid_index)
+    |> cast(attrs, [
+      :guid,
+      :title,
+      :url,
+      :creator,
+      :date,
+      :content,
+      :read,
+      :read_date,
+      :tombstone,
+      :feed_id
+    ])
+    |> validate_required([:guid, :url, :date, :content, :feed_id])
+    |> unique_constraint([:feed_id, :guid], name: :items_feed_guid_index)
   end
 
   def exists?(feed_id, guid) do

lib/frenzy/task/create_item.ex

@@ -1,7 +1,7 @@
 defmodule Frenzy.Task.CreateItem do
   require Logger
   use Task
-  alias Frenzy.Repo
+  alias Frenzy.{Repo, Item}
 
   @spec start_link(Frenzy.Feed.t(), FeedParser.Item.t()) :: {:ok, pid()}
   def start_link(feed, entry) do
@@ -29,7 +29,8 @@ defmodule Frenzy.Task.CreateItem do
       end
 
     item_params = %{
-      guid: entry.guid,
+      # fallback to url if guid isn't present
+      guid: entry.guid || url,
       title: entry.title,
       url: url,
       date: date,
@@ -61,36 +62,41 @@ defmodule Frenzy.Task.CreateItem do
         {:ok, item_params}
       end
 
+    changeset =
       case result do
         {:error, error} ->
           Logger.error(error)
+          :error
 
         {:ok, item_params} ->
-        changeset = Ecto.build_assoc(feed, :items, item_params)
-
-        case Repo.insert(changeset) do
-          {:ok, item} ->
-            item
-
-          {:error, changeset} ->
-            Logger.error("Error inserting item #{entry.guid}")
-            Logger.error(changeset)
-        end
+          item_params = Map.put(item_params, :feed_id, feed.id)
+          Item.changeset(%Item{}, item_params)
 
         :tombstone ->
-        changeset =
-          Ecto.build_assoc(feed, :items, %{
+          Item.changeset(%Item{}, %{
             guid: item_params.guid,
             tombstone: true
           })
+      end
 
+    case changeset do
+      nil ->
+        nil
+
+      changeset ->
         case Repo.insert(changeset) do
           {:ok, item} ->
             item
 
           {:error, changeset} ->
-            Logger.error("Error inserting tombstone for #{entry.guid}")
-            Logger.error(changeset)
+            with [feed_id: {_, list}] <- changeset.errors,
+                 true <- {:constraint_name, "items_feed_guid_index"} in list do
+              Logger.warn("Did not insert duplicate item for #{item_params.guid}")
+            else
+              _ ->
+                Logger.error("Error inserting item #{item_params.guid}")
+                Logger.error(changeset.errors)
+            end
         end
     end