Add support for importing notebook from URL query parameter (#598)

* Add support for importing notebook from URL query

* Update desc

* Update URL and redirect to import form on error

* Update tests

* Remove URL scope

lib/livebook_web/live/home_live.ex

@@ -139,7 +139,8 @@ defmodule LivebookWeb.HomeLive do
             id: "import",
             modal_class: "w-full max-w-xl",
             return_to: Routes.home_path(@socket, :page),
-            tab: @tab %>
+            tab: @tab,
+            import_opts: @import_opts %>
     <% end %>
     """
   end
@@ -220,8 +221,23 @@ defmodule LivebookWeb.HomeLive do
     {:noreply, assign(socket, session: session)}
   end
 
-  def handle_params(%{"tab" => tab}, _url, socket) do
-    {:noreply, assign(socket, tab: tab)}
+  def handle_params(%{"tab" => tab} = params, _url, %{assigns: %{live_action: :import}} = socket) do
+    import_opts = [url: params["url"]]
+    {:noreply, assign(socket, tab: tab, import_opts: import_opts)}
+  end
+
+  def handle_params(%{"url" => url}, _url, %{assigns: %{live_action: :public_import}} = socket) do
+    url
+    |> Livebook.ContentLoader.rewrite_url()
+    |> Livebook.ContentLoader.fetch_content()
+    |> case do
+      {:ok, content} ->
+        socket = import_content(socket, content, origin: {:url, url})
+        {:noreply, socket}
+
+      {:error, _message} ->
+        {:noreply, push_patch(socket, to: Routes.home_path(socket, :import, "url", url: url))}
+    end
   end
 
   def handle_params(_params, _url, socket), do: {:noreply, socket}
@@ -331,10 +347,8 @@ defmodule LivebookWeb.HomeLive do
   end
 
   def handle_info({:import_content, content, session_opts}, socket) do
-    {notebook, messages} = Livebook.LiveMarkdown.Import.notebook_from_markdown(content)
-    socket = put_import_flash_messages(socket, messages)
-    session_opts = Keyword.merge(session_opts, notebook: notebook)
-    {:noreply, create_session(socket, session_opts)}
+    socket = import_content(socket, content, session_opts)
+    {:noreply, socket}
   end
 
   def handle_info(
@@ -391,4 +405,11 @@ defmodule LivebookWeb.HomeLive do
     time_words = created_at |> DateTime.to_naive() |> Livebook.Utils.Time.time_ago_in_words()
     time_words <> " ago"
   end
+
+  defp import_content(socket, content, session_opts) do
+    {notebook, messages} = Livebook.LiveMarkdown.Import.notebook_from_markdown(content)
+    socket = put_import_flash_messages(socket, messages)
+    session_opts = Keyword.merge(session_opts, notebook: notebook)
+    create_session(socket, session_opts)
+  end
 end

lib/livebook_web/live/home_live/import_component.ex

@@ -27,7 +27,7 @@ defmodule LivebookWeb.HomeLive.ImportComponent do
         </div>
       </div>
       <div>
-        <%= live_component component_for_tab(@tab), id: "import-#{@tab}" %>
+        <%= live_component component_for_tab(@tab), [{:id, "import-#{@tab}"} | @import_opts] %>
       </div>
     </div>
     """

lib/livebook_web/live/home_live/import_url_component.ex

@@ -8,6 +8,15 @@ defmodule LivebookWeb.HomeLive.ImportUrlComponent do
     {:ok, assign(socket, url: "", error_message: nil)}
   end
 
+  @impl true
+  def update(assigns, socket) do
+    if url = assigns[:url] do
+      {:ok, do_import(socket, url)}
+    else
+      {:ok, socket}
+    end
+  end
+
   @impl true
   def render(assigns) do
     ~H"""
@@ -45,16 +54,20 @@ defmodule LivebookWeb.HomeLive.ImportUrlComponent do
   end
 
   def handle_event("import", %{"data" => %{"url" => url}}, socket) do
+    {:noreply, do_import(socket, url)}
+  end
+
+  defp do_import(socket, url) do
     url
     |> ContentLoader.rewrite_url()
     |> ContentLoader.fetch_content()
     |> case do
       {:ok, content} ->
         send(self(), {:import_content, content, [origin: {:url, url}]})
-        {:noreply, socket}
+        socket
 
       {:error, message} ->
-        {:noreply, assign(socket, error_message: Utils.upcase_first(message))}
+        assign(socket, url: url, error_message: Utils.upcase_first(message))
     end
   end
 end

lib/livebook_web/router.ex

@@ -52,6 +52,13 @@ defmodule LivebookWeb.Router do
       home_app: {"Livebook", :livebook}
   end
 
+  # Public URLs that people may be directed to
+  scope "/", LivebookWeb do
+    pipe_through [:browser, :auth]
+
+    live "/import", HomeLive, :public_import
+  end
+
   scope "/", LivebookWeb do
     pipe_through :browser
 

test/livebook_web/live/home_live_test.exs

@@ -208,6 +208,44 @@ defmodule LivebookWeb.HomeLiveTest do
     end
   end
 
+  describe "public import endpoint" do
+    test "imports notebook from the given url and redirects to the new session", %{conn: conn} do
+      bypass = Bypass.open()
+
+      Bypass.expect_once(bypass, "GET", "/notebook", fn conn ->
+        conn
+        |> Plug.Conn.put_resp_content_type("text/plain")
+        |> Plug.Conn.resp(200, "# My notebook")
+      end)
+
+      notebook_url = "http://localhost:#{bypass.port}/notebook"
+
+      assert {:error, {:live_redirect, %{to: to}}} =
+               live(conn, "/import?url=#{URI.encode_www_form(notebook_url)}")
+
+      {:ok, view, _} = live(conn, to)
+      assert render(view) =~ "My notebook"
+    end
+
+    test "redirects to the import form on error", %{conn: conn} do
+      bypass = Bypass.open()
+
+      Bypass.expect(bypass, "GET", "/notebook", fn conn ->
+        Plug.Conn.resp(conn, 500, "Error")
+      end)
+
+      notebook_url = "http://localhost:#{bypass.port}/notebook"
+
+      assert {:error, {:live_redirect, %{to: to}}} =
+               live(conn, "/import?url=#{URI.encode_www_form(notebook_url)}")
+
+      assert to == "/home/import/url?url=#{URI.encode_www_form(notebook_url)}"
+
+      {:ok, view, _} = live(conn, to)
+      assert render(view) =~ notebook_url
+    end
+  end
+
   # Helpers
 
   defp test_notebook_path(name) do