Prepare to make Explore section extensible (#626)

lib/livebook/notebook/explore.ex

@@ -1,50 +1,3 @@
-defmodule Livebook.Notebook.Explore.Utils do
-  @moduledoc false
-
-  @doc """
-  Defines a module attribute `attr` with notebook info.
-  """
-  defmacro defnotebook(attr, props) do
-    quote bind_quoted: [attr: attr, props: props] do
-      {path, notebook_info} = Livebook.Notebook.Explore.Utils.fetch_notebook!(attr, props)
-
-      @external_resource path
-
-      Module.put_attribute(__MODULE__, attr, notebook_info)
-    end
-  end
-
-  def fetch_notebook!(attr, props) do
-    name = Atom.to_string(attr)
-    path = Path.join([__DIR__, "explore", name <> ".livemd"])
-
-    markdown = File.read!(path)
-    # Parse the file to ensure no warnings and read the title.
-    # However, in the info we keep just the file contents to save on memory.
-    {notebook, []} = Livebook.LiveMarkdown.Import.notebook_from_markdown(markdown)
-
-    images =
-      props
-      |> Keyword.get(:image_names, [])
-      |> Map.new(fn image_name ->
-        path = Path.join([__DIR__, "explore", "images", image_name])
-        content = File.read!(path)
-        {image_name, content}
-      end)
-
-    notebook_info = %{
-      slug: String.replace(name, "_", "-"),
-      livemd: markdown,
-      title: notebook.name,
-      description: Keyword.fetch!(props, :description),
-      image_url: Keyword.fetch!(props, :image_url),
-      images: images
-    }
-
-    {path, notebook_info}
-  end
-end
-
 defmodule Livebook.Notebook.Explore do
   @moduledoc false
 
@@ -58,78 +11,99 @@ defmodule Livebook.Notebook.Explore do
     end
   end
 
-  import Livebook.Notebook.Explore.Utils
-
-  defnotebook(:intro_to_livebook,
-    description: "Get to know Livebook, see how it works and explore its features.",
-    image_url: "/images/logo.png"
-  )
-
-  defnotebook(:distributed_portals_with_elixir,
-    description:
-      "A fast-paced introduction to the Elixir language by building distributed data-transfer portals.",
-    image_url: "/images/elixir-portal.jpeg",
-    image_names: ["portal-drop.jpeg", "portal-list.jpeg"]
-  )
-
-  defnotebook(:elixir_and_livebook,
-    description: "Learn how to use some of Elixir and Livebook's unique features together.",
-    image_url: "/images/elixir.png"
-  )
-
-  defnotebook(:intro_to_nx,
-    description:
-      "Enter Numerical Elixir, experience the power of multi-dimensional arrays of numbers.",
-    image_url: "/images/nx.png"
-  )
-
-  defnotebook(:intro_to_axon,
-    description: "Build Neural Networks in Elixir using a high-level, composable API.",
-    image_url: "/images/axon.png"
-  )
-
-  defnotebook(:intro_to_vega_lite,
-    description: "Learn how to quickly create numerous plots for your data.",
-    image_url: "/images/vega_lite.png"
-  )
-
-  defnotebook(:vm_introspection,
-    description: "Extract and visualize information about a remote running node.",
-    image_url: "/images/vm_introspection.png"
-  )
-
-  defnotebook(:intro_to_kino,
-    description: "Display and control rich and interactive widgets in Livebook.",
-    image_url: "/images/kino.png"
-  )
-
   @type notebook_info :: %{
           slug: String.t(),
           livemd: String.t(),
           title: String.t(),
           description: String.t(),
-          image_url: String.t(),
+          cover_url: String.t(),
           images: images()
         }
 
   @type images :: %{String.t() => binary()}
 
+  infos = [
+    %{
+      path: Path.join(__DIR__, "explore/intro_to_livebook.livemd"),
+      description: "Get to know Livebook, see how it works and explore its features.",
+      cover_url: "/images/logo.png"
+    },
+    %{
+      path: Path.join(__DIR__, "explore/distributed_portals_with_elixir.livemd"),
+      description:
+        "A fast-paced introduction to the Elixir language by building distributed data-transfer portals.",
+      cover_url: "/images/elixir-portal.jpeg",
+      image_names: ["portal-drop.jpeg", "portal-list.jpeg"]
+    },
+    %{
+      path: Path.join(__DIR__, "explore/elixir_and_livebook.livemd"),
+      description: "Learn how to use some of Elixir and Livebook's unique features together.",
+      cover_url: "/images/elixir.png"
+    },
+    %{
+      path: Path.join(__DIR__, "explore/intro_to_vega_lite.livemd"),
+      description: "Learn how to quickly create numerous plots for your data.",
+      cover_url: "/images/vega_lite.png"
+    },
+    %{
+      path: Path.join(__DIR__, "explore/intro_to_kino.livemd"),
+      description: "Display and control rich and interactive widgets in Livebook.",
+      cover_url: "/images/kino.png"
+    },
+    %{
+      path: Path.join(__DIR__, "explore/intro_to_nx.livemd"),
+      description:
+        "Enter Numerical Elixir, experience the power of multi-dimensional arrays of numbers.",
+      cover_url: "/images/nx.png"
+    },
+    # %{
+    #   path: Path.join(__DIR__, "explore/intro_to_axon.livemd"),
+    #   description: "Build Neural Networks in Elixir using a high-level, composable API.",
+    #   cover_url: "/images/axon.png"
+    # },
+    %{
+      path: Path.join(__DIR__, "explore/vm_introspection.livemd"),
+      description: "Extract and visualize information about a remote running node.",
+      cover_url: "/images/vm_introspection.png"
+    }
+  ]
+
+  notebook_infos =
+    for info <- infos do
+      path = Map.fetch!(info, :path)
+      @external_resource path
+
+      markdown = File.read!(path)
+      # Parse the file to ensure no warnings and read the title.
+      # However, in the info we keep just the file contents to save on memory.
+      {notebook, []} = Livebook.LiveMarkdown.Import.notebook_from_markdown(markdown)
+
+      images =
+        info
+        |> Map.get(:image_names, [])
+        |> Map.new(fn image_name ->
+          path = Path.join([Path.dirname(path), "images", image_name])
+          content = File.read!(path)
+          {image_name, content}
+        end)
+
+      slug = info[:slug] || path |> Path.basename() |> Path.rootname() |> String.replace("_", "-")
+
+      %{
+        slug: slug,
+        livemd: markdown,
+        title: notebook.name,
+        description: Map.fetch!(info, :description),
+        cover_url: Map.fetch!(info, :cover_url),
+        images: images
+      }
+    end
+
   @doc """
   Returns a list of example notebooks with metadata.
   """
   @spec notebook_infos() :: list(notebook_info())
-  def notebook_infos() do
-    [
-      @intro_to_livebook,
-      @distributed_portals_with_elixir,
-      @elixir_and_livebook,
-      @intro_to_vega_lite,
-      @intro_to_kino,
-      @intro_to_nx,
-      @vm_introspection
-      # , @intro_to_axon
-    ]
-  end
+  def notebook_infos(), do: unquote(Macro.escape(notebook_infos))
 
   @doc """
   Finds explore notebook by slug and returns the parsed data structure.

lib/livebook_web/live/explore_helpers.ex

@@ -11,7 +11,7 @@ defmodule LivebookWeb.ExploreHelpers do
     <div class="flex flex-col">
       <%= live_redirect to: Routes.explore_path(@socket, :notebook, @notebook_info.slug),
             class: "flex items-center justify-center p-6 border-2 border-gray-100 rounded-t-2xl h-[150px]" do %>
-        <img src={@notebook_info.image_url} class="max-h-full max-w-[75%]" />
+        <img src={@notebook_info.cover_url} class="max-h-full max-w-[75%]" />
       <% end %>
       <div class="px-6 py-4 bg-gray-100 rounded-b-2xl flex-grow">
         <%= live_redirect @notebook_info.title,

lib/livebook_web/live/explore_live.ex

@@ -63,7 +63,7 @@ defmodule LivebookWeb.ExploreLive do
               </div>
             </div>
             <div class="flex-grow hidden md:flex flex items-center justify-center">
-              <img src={@lead_notebook_info.image_url} height="120" width="120" alt="livebook" />
+              <img src={@lead_notebook_info.cover_url} height="120" width="120" alt="livebook" />
             </div>
           </div>
           <div class="grid grid-cols-1 md:grid-cols-2 gap-4">