General cleanup

lib/code_corps/github/adapters/task.ex

@@ -1,7 +1,7 @@
 defmodule CodeCorps.GitHub.Adapters.Task do
   @moduledoc """
   Used to adapt a GitHub issue payload into attributes for creating or updating
-  a `CodeCorps.Task`.
+  a `CodeCorps.Task` and vice-versa.
   """
 
   alias CodeCorps.{
@@ -18,18 +18,26 @@ defmodule CodeCorps.GitHub.Adapters.Task do
     {:title, ["title"]}
   ]
 
+  @doc ~S"""
+  Converts a GitHub issue payled into a set of attributes used to update or
+  create a `Task` record.
+  """
   @spec from_issue(map) :: map
   def from_issue(%{} = payload) do
     payload |> MapTransformer.transform(@mapping)
   end
 
+  @autogenerated_github_keys ~w(created_at number updated_at)
+
+  @doc ~S"""
+  Converts a `Task` into a set of attributes used to update or create an
+  associated GitHub issue
+  """
   @spec to_issue(Task.t) :: map
   def to_issue(%Task{} = task) do
     task
     |> Map.from_struct
     |> MapTransformer.transform_inverse(@mapping)
-    |> Map.delete("created_at")
-    |> Map.delete("number")
-    |> Map.delete("updated_at")
+    |> Map.drop(@autogenerated_github_keys)
   end
 end

lib/code_corps/github/event/issues/changeset_builder.ex

@@ -16,7 +16,10 @@ defmodule CodeCorps.GitHub.Event.Issues.ChangesetBuilder do
   alias Ecto.Changeset
 
   @doc ~S"""
-  Constructs a changeset for syncing a task when processing an Issues webhook
+  Constructs a changeset for syncing a `Task` when processing an Issues or
+  IssueComment webhook.
+
+  The changeset can be used to create or update a `Task`
   """
   @spec build_changeset(Task.t, map, ProjectGithubRepo.t, User.t) :: Changeset.t
   def build_changeset(
@@ -31,6 +34,8 @@ defmodule CodeCorps.GitHub.Event.Issues.ChangesetBuilder do
     end
   end
 
+  @create_attrs ~w(created_at github_issue_number markdown modified_at status title)a
+  @spec create_changeset(Task.t, map, ProjectGithubRepo.t, User.t) :: Changeset.t
   defp create_changeset(
     %Task{} = task,
     %{} = issue_attrs,
@@ -41,7 +46,7 @@ defmodule CodeCorps.GitHub.Event.Issues.ChangesetBuilder do
       TaskList |> Repo.get_by(project_id: project_id, inbox: true)
 
     task
-    |> Changeset.cast(TaskAdapter.from_issue(issue_attrs), [:created_at, :github_issue_number, :markdown, :modified_at, :status, :title])
+    |> Changeset.cast(TaskAdapter.from_issue(issue_attrs), @create_attrs)
     |> MarkdownRendererService.render_markdown_to_html(:markdown, :body)
     |> Changeset.put_change(:created_on, "github")
     |> Changeset.put_change(:github_repo_id, github_repo_id)
@@ -55,9 +60,11 @@ defmodule CodeCorps.GitHub.Event.Issues.ChangesetBuilder do
     |> Changeset.assoc_constraint(:user)
   end
 
-  defp update_changeset(%Task{} = task, issue_attrs) do
+  @update_attrs ~w(github_issue_number markdown modified_at status title)a
+  @spec update_changeset(Task.t, map) :: Changeset.t
+  defp update_changeset(%Task{} = task, %{} = issue_attrs) do
     task
-    |> Changeset.cast(TaskAdapter.from_issue(issue_attrs), [:github_issue_number, :markdown, :modified_at, :status, :title])
+    |> Changeset.cast(TaskAdapter.from_issue(issue_attrs), @update_attrs)
     |> MarkdownRendererService.render_markdown_to_html(:markdown, :body)
     |> Changeset.put_change(:updated_on, "github")
     |> Changeset.validate_required([:project_id, :title, :user_id])