Add drag and drop actions for notebook files (#2096)

Co-authored-by: José Valim <jose.valim@dashbit.co>

assets/css/js_interop.css

@@ -14,7 +14,7 @@ solely client-side operations.
 }
 
 [phx-hook="Dropzone"][data-js-dragging] {
-  @apply bg-yellow-100 border-yellow-300;
+  @apply bg-blue-100 border-blue-300;
 }
 
 /* === Session === */
@@ -73,6 +73,10 @@ solely client-side operations.
   @apply hidden;
 }
 
+[data-el-session]:not([data-js-dragging]) [data-el-insert-drop-area] {
+  @apply hidden;
+}
+
 [data-el-cell][data-js-focused] {
   @apply border-blue-300 border-opacity-100;
 }

assets/js/hooks/session.js

@@ -142,6 +142,8 @@ const Session = {
       (event) => this.toggleCollapseAllSections()
     );
 
+    this.initializeDragAndDrop();
+
     window.addEventListener(
       "phx:page-loading-stop",
       () => {
@@ -707,6 +709,45 @@ const Session = {
     }
   },
 
+  /**
+   * Initializes drag and drop event handlers.
+   */
+  initializeDragAndDrop() {
+    let draggedEl = null;
+
+    this.el.addEventListener("dragstart", (event) => {
+      draggedEl = event.target;
+      this.el.setAttribute("data-js-dragging", "");
+    });
+
+    this.el.addEventListener("dragend", (event) => {
+      this.el.removeAttribute("data-js-dragging");
+    });
+
+    this.el.addEventListener("dragover", (event) => {
+      const dropEl = event.target.closest(`[data-el-insert-drop-area]`);
+
+      if (dropEl) {
+        event.preventDefault();
+      }
+    });
+
+    this.el.addEventListener("drop", (event) => {
+      const dropEl = event.target.closest(`[data-el-insert-drop-area]`);
+
+      if (draggedEl.matches("[data-el-file-entry]") && dropEl) {
+        const fileEntryName = draggedEl.getAttribute("data-name");
+        const sectionId = dropEl.getAttribute("data-section-id") || null;
+        const cellId = dropEl.getAttribute("data-cell-id") || null;
+        this.pushEvent("insert_file", {
+          file_entry_name: fileEntryName,
+          section_id: sectionId,
+          cell_id: cellId,
+        });
+      }
+    });
+  },
+
   // User action handlers (mostly keybindings)
 
   toggleSectionsList() {

lib/livebook/notebook.ex

@@ -843,8 +843,10 @@ defmodule Livebook.Notebook do
   """
   @spec validate_file_entry_name(Ecto.Changeset.t(), atom()) :: Ecto.Changeset.t()
   def validate_file_entry_name(changeset, field) do
-    Ecto.Changeset.validate_format(changeset, field, ~r/^[\w-.]+$/,
+    changeset
+    |> Ecto.Changeset.validate_format(field, ~r/^[\w-.]+$/,
       message: "should contain only alphanumeric characters, dash, underscore and dot"
     )
+    |> Ecto.Changeset.validate_format(field, ~r/\.\w+$/, message: "should end with an extension")
   end
 end

lib/livebook/runtime.ex

@@ -273,15 +273,17 @@ defprotocol Livebook.Runtime do
           requirement_presets:
             list(%{
               name: String.t(),
-              packages: list(%{name: String.t(), dependency: dependency()})
+              packages: list(package())
             })
         }
 
+  @type package :: %{name: String.t(), dependency: dependency()}
+
   @type dependency :: term()
 
-  @type search_packages_response :: {:ok, list(package())} | {:error, String.t()}
+  @type search_packages_response :: {:ok, list(package_details())} | {:error, String.t()}
 
-  @type package :: %{
+  @type package_details :: %{
           name: String.t(),
           version: String.t(),
           description: String.t() | nil,
@@ -290,19 +292,46 @@ defprotocol Livebook.Runtime do
         }
 
   @typedoc """
-  An information about a predefined code block.
+  An information about a predefined code snippets.
   """
-  @type code_block_definition :: %{
+  @type snippet_definition :: example_snippet_definition() | file_action_snippet_definition()
+
+  @typedoc """
+  Code snippet with fixed source, serving as an example or boilerplate.
+  """
+  @type example_snippet_definition :: %{
+          type: :example,
           name: String.t(),
           icon: String.t(),
           variants:
             list(%{
               name: String.t(),
               source: String.t(),
-              packages: list(%{name: String.t(), dependency: dependency()})
+              packages: list(package())
             })
         }
 
+  @typedoc """
+  Code snippet for acting on files of the given type.
+
+  The action is applicable to files matching any of the specified types,
+  where a type can be either:
+
+    * specific MIME type, like `text/csv`
+    * MIME type family, like `image/*`
+    * file extension, like `.csv`
+
+  The source is expected to include `{{NAME}}`, which is replaced with
+  the actual file name.
+  """
+  @type file_action_snippet_definition :: %{
+          type: :file_action,
+          file_types: :any | list(String.t()),
+          description: String.t(),
+          source: String.t(),
+          packages: list(package())
+        }
+
   @typedoc """
   A JavaScript view definition.
 
@@ -615,10 +644,10 @@ defprotocol Livebook.Runtime do
   def has_dependencies?(runtime, dependencies)
 
   @doc """
-  Returns a list of predefined code blocks.
+  Returns a list of predefined code snippets.
   """
-  @spec code_block_definitions(t()) :: list(code_block_definition())
-  def code_block_definitions(runtime)
+  @spec snippet_definitions(t()) :: list(snippet_definition())
+  def snippet_definitions(runtime)
 
   @doc """
   Looks up packages matching the given search.

lib/livebook/runtime/attached.ex

@@ -165,8 +165,8 @@ defimpl Livebook.Runtime, for: Livebook.Runtime.Attached do
     RuntimeServer.has_dependencies?(runtime.server_pid, dependencies)
   end
 
-  def code_block_definitions(_runtime) do
-    Livebook.Runtime.Definitions.code_block_definitions()
+  def snippet_definitions(_runtime) do
+    Livebook.Runtime.Definitions.snippet_definitions()
   end
 
   def search_packages(_runtime, _send_to, _search) do

lib/livebook/runtime/definitions.ex

@@ -46,6 +46,11 @@ defmodule Livebook.Runtime.Definitions do
     dependency: %{dep: {:kino_explorer, "~> 0.1.4"}, config: []}
   }
 
+  jason = %{
+    name: "jason",
+    dependency: %{dep: {:jason, "~> 1.4"}, config: []}
+  }
+
   windows? = match?({:win32, _}, :os.type())
   nx_backend_package = if(windows?, do: torchx, else: exla)
 
@@ -159,8 +164,10 @@ defmodule Livebook.Runtime.Definitions do
     }
   ]
 
-  @code_block_definitions [
+  @snippet_definitions [
+    # Examples
     %{
+      type: :example,
       name: "Form",
       icon: "bill-line",
       variants: [
@@ -184,10 +191,47 @@ defmodule Livebook.Runtime.Definitions do
           packages: [kino]
         }
       ]
+    },
+    # File actions
+    %{
+      type: :file_action,
+      file_types: :any,
+      description: "Read file content",
+      source: """
+      content =
+        Kino.FS.file_path("{{NAME}}")
+        |> File.read!()\
+      """,
+      packages: [kino]
+    },
+    %{
+      type: :file_action,
+      file_types: ["application/json"],
+      description: "Parse JSON content",
+      source: """
+      data =
+        Kino.FS.file_path("{{NAME}}")
+        |> File.read!()
+        |> Jason.decode!()
+
+      Kino.Tree.new(data)\
+      """,
+      packages: [kino, jason]
+    },
+    %{
+      type: :file_action,
+      file_types: ["text/csv"],
+      description: "Create a dataframe",
+      source: """
+      df =
+        Kino.FS.file_path("{{NAME}}")
+        |> Explorer.DataFrame.from_csv!()\
+      """,
+      packages: [kino, kino_explorer]
     }
   ]
 
   def smart_cell_definitions(), do: @smart_cell_definitions
 
-  def code_block_definitions(), do: @code_block_definitions
+  def snippet_definitions(), do: @snippet_definitions
 end

lib/livebook/runtime/dependencies.ex

@@ -255,7 +255,7 @@ defmodule Livebook.Runtime.Dependencies do
   through the given list of packages.
   """
   @spec search_packages_in_list(
-          list(Livebook.Runtime.package()),
+          list(Livebook.Runtime.package_details()),
           pid(),
           String.t()
         ) :: reference()

lib/livebook/runtime/elixir_standalone.ex

@@ -167,8 +167,8 @@ defimpl Livebook.Runtime, for: Livebook.Runtime.ElixirStandalone do
     RuntimeServer.has_dependencies?(runtime.server_pid, dependencies)
   end
 
-  def code_block_definitions(_runtime) do
-    Livebook.Runtime.Definitions.code_block_definitions()
+  def snippet_definitions(_runtime) do
+    Livebook.Runtime.Definitions.snippet_definitions()
   end
 
   def search_packages(_runtime, send_to, search) do

lib/livebook/runtime/embedded.ex

@@ -135,8 +135,8 @@ defimpl Livebook.Runtime, for: Livebook.Runtime.Embedded do
     RuntimeServer.has_dependencies?(runtime.server_pid, dependencies)
   end
 
-  def code_block_definitions(_runtime) do
-    Livebook.Runtime.Definitions.code_block_definitions()
+  def snippet_definitions(_runtime) do
+    Livebook.Runtime.Definitions.snippet_definitions()
   end
 
   def search_packages(_runtime, send_to, search) do

lib/livebook_web/live/session_live.ex

@@ -410,7 +410,7 @@ defmodule LivebookWeb.SessionLive do
               client_id={@client_id}
               runtime={@data_view.runtime}
               smart_cell_definitions={@data_view.smart_cell_definitions}
-              code_block_definitions={@data_view.code_block_definitions}
+              example_snippet_definitions={@data_view.example_snippet_definitions}
               installing?={@data_view.installing?}
               allowed_uri_schemes={@allowed_uri_schemes}
               section_view={section_view}
@@ -527,6 +527,22 @@ defmodule LivebookWeb.SessionLive do
       />
     </.modal>
 
+    <.modal
+      :if={@live_action == :insert_file}
+      id="insert-file-modal"
+      show
+      width={:medium}
+      patch={@self_path}
+    >
+      <.live_component
+        module={LivebookWeb.SessionLive.InsertFileComponent}
+        id="insert-file"
+        session={@session}
+        return_to={@self_path}
+        insert_file_metadata={@insert_file_metadata}
+      />
+    </.modal>
+
     <.modal :if={@live_action == :bin} id="bin-modal" show width={:big} patch={@self_path}>
       <.live_component
         module={LivebookWeb.SessionLive.BinComponent}
@@ -925,15 +941,16 @@ defmodule LivebookWeb.SessionLive do
     {:noreply, assign(socket, cell: cell)}
   end
 
-  def handle_params(%{"section_id" => section_id, "cell_id" => cell_id}, _url, socket)
-      when socket.assigns.live_action == :insert_image do
-    cell_id =
-      case cell_id do
-        "" -> nil
-        id -> id
-      end
+  def handle_params(%{}, _url, socket)
+      when socket.assigns.live_action == :insert_image and
+             not is_map_key(socket.assigns, :insert_image_metadata) do
+    {:noreply, redirect_to_self(socket)}
+  end
 
-    {:noreply, assign(socket, insert_image_metadata: %{section_id: section_id, cell_id: cell_id})}
+  def handle_params(%{}, _url, socket)
+      when socket.assigns.live_action == :insert_file and
+             not is_map_key(socket.assigns, :insert_file_metadata) do
+    {:noreply, redirect_to_self(socket)}
   end
 
   def handle_params(%{"path_parts" => path_parts}, requested_url, socket)
@@ -1015,43 +1032,33 @@ defmodule LivebookWeb.SessionLive do
     {:noreply, insert_cell_below(socket, params)}
   end
 
-  def handle_event("insert_code_block_below", params, socket) do
+  def handle_event("insert_example_snippet_below", params, socket) do
     data = socket.private.data
     %{"section_id" => section_id, "cell_id" => cell_id} = params
 
-    case code_block_definition_by_name(data, params["definition_name"]) do
-      {:ok, definition} ->
-        variant = Enum.fetch!(definition.variants, params["variant_idx"])
-        dependencies = Enum.map(variant.packages, & &1.dependency)
+    if Livebook.Runtime.connected?(socket.private.data.runtime) do
+      case example_snippet_definition_by_name(data, params["definition_name"]) do
+        {:ok, definition} ->
+          variant = Enum.fetch!(definition.variants, params["variant_idx"])
 
-        has_dependencies? =
-          dependencies == [] or Livebook.Runtime.has_dependencies?(data.runtime, dependencies)
-
-        cond do
-          has_dependencies? ->
-            insert_code_block_below(socket, variant, section_id, cell_id)
-            {:noreply, socket}
-
-          Livebook.Runtime.fixed_dependencies?(data.runtime) ->
-            {:noreply,
-             put_flash(socket, :error, "This runtime doesn't support adding dependencies")}
-
-          true ->
-            on_confirm = fn socket ->
-              case insert_code_block_below(socket, variant, section_id, cell_id) do
-                :ok -> add_dependencies_and_reevaluate(socket, dependencies)
-                :error -> socket
+          socket =
+            ensure_packages_then(socket, variant.packages, definition.name, "block", fn socket ->
+              with {:ok, section, index} <-
+                     section_with_next_index(socket.private.data.notebook, section_id, cell_id) do
+                attrs = %{source: variant.source}
+                Session.insert_cell(socket.assigns.session.pid, section.id, index, :code, attrs)
+                {:ok, socket}
               end
-            end
+            end)
 
-            socket =
-              confirm_add_packages(socket, on_confirm, variant.packages, definition.name, "block")
+          {:noreply, socket}
 
-            {:noreply, socket}
-        end
-
-      _ ->
-        {:noreply, socket}
+        _ ->
+          {:noreply, socket}
+      end
+    else
+      reason = "To insert this block, you need a connected runtime."
+      {:noreply, confirm_setup_default_runtime(socket, reason)}
     end
   end
 
@@ -1066,32 +1073,19 @@ defmodule LivebookWeb.SessionLive do
             Enum.at(definition.requirement_presets, preset_idx)
           end
 
-        if preset == nil do
-          insert_smart_cell_below(socket, definition, section_id, cell_id)
-          {:noreply, socket}
-        else
-          on_confirm = fn socket ->
-            case insert_smart_cell_below(socket, definition, section_id, cell_id) do
-              :ok ->
-                dependencies = Enum.map(preset.packages, & &1.dependency)
-                add_dependencies_and_reevaluate(socket, dependencies)
+        packages = if(preset, do: preset.packages, else: [])
 
-              :error ->
-                socket
+        socket =
+          ensure_packages_then(socket, packages, definition.name, "smart cell", fn socket ->
+            with {:ok, section, index} <-
+                   section_with_next_index(socket.private.data.notebook, section_id, cell_id) do
+              attrs = %{kind: definition.kind}
+              Session.insert_cell(socket.assigns.session.pid, section.id, index, :smart, attrs)
+              {:ok, socket}
             end
-          end
+          end)
 
-          socket =
-            confirm_add_packages(
-              socket,
-              on_confirm,
-              preset.packages,
-              definition.name,
-              "smart cell"
-            )
-
-          {:noreply, socket}
-        end
+        {:noreply, socket}
 
       _ ->
         {:noreply, socket}
@@ -1336,24 +1330,7 @@ defmodule LivebookWeb.SessionLive do
   end
 
   def handle_event("setup_default_runtime", %{"reason" => reason}, socket) do
-    on_confirm = fn socket ->
-      {status, socket} = connect_runtime(socket)
-
-      if status == :ok do
-        Session.queue_cell_evaluation(socket.assigns.session.pid, Cell.setup_cell_id())
-      end
-
-      socket
-    end
-
-    {:noreply,
-     confirm(socket, on_confirm,
-       title: "Setup runtime",
-       description: "#{reason} Do you want to connect and setup the default one?",
-       confirm_text: "Setup runtime",
-       confirm_icon: "play-line",
-       danger: false
-     )}
+    {:noreply, confirm_setup_default_runtime(socket, reason)}
   end
 
   def handle_event("disconnect_runtime", %{}, socket) do
@@ -1499,9 +1476,7 @@ defmodule LivebookWeb.SessionLive do
   end
 
   def handle_event("review_file_entry_access", %{"name" => name}, socket) do
-    file_entry = Enum.find(socket.private.data.notebook.file_entries, &(&1.name == name))
-
-    if file_entry do
+    if file_entry = find_file_entry(socket, name) do
       on_confirm = fn socket ->
         Session.allow_file_entry(socket.assigns.session.pid, file_entry.name)
         socket
@@ -1533,6 +1508,77 @@ defmodule LivebookWeb.SessionLive do
     end
   end
 
+  def handle_event("insert_image", params, socket) do
+    {:noreply,
+     socket
+     |> assign(
+       insert_image_metadata: %{section_id: params["section_id"], cell_id: params["cell_id"]}
+     )
+     |> push_patch(to: ~p"/sessions/#{socket.assigns.session.id}/insert-image")}
+  end
+
+  def handle_event(
+        "insert_file",
+        %{"section_id" => section_id, "cell_id" => cell_id, "file_entry_name" => file_entry_name},
+        socket
+      ) do
+    if file_entry = find_file_entry(socket, file_entry_name) do
+      if Livebook.Runtime.connected?(socket.private.data.runtime) do
+        {:noreply,
+         socket
+         |> assign(
+           insert_file_metadata: %{
+             section_id: section_id,
+             cell_id: cell_id,
+             file_entry: file_entry,
+             handlers: handlers_for_file_entry(file_entry, socket.private.data.runtime)
+           }
+         )
+         |> push_patch(to: ~p"/sessions/#{socket.assigns.session.id}/insert-file")}
+      else
+        reason = "To see the available options, you need a connected runtime."
+        {:noreply, confirm_setup_default_runtime(socket, reason)}
+      end
+    else
+      {:noreply, socket}
+    end
+  end
+
+  def handle_event("insert_file_action", %{"idx" => idx}, socket) do
+    %{section_id: section_id, cell_id: cell_id, file_entry: file_entry, handlers: handlers} =
+      socket.assigns.insert_file_metadata
+
+    handler = Enum.fetch!(handlers, idx)
+    source = String.replace(handler.definition.source, "{{NAME}}", file_entry.name)
+
+    socket =
+      socket
+      |> redirect_to_self()
+      |> ensure_packages_then(
+        handler.definition.packages,
+        handler.definition.description,
+        "action",
+        fn socket ->
+          with {:ok, section, index} <-
+                 section_with_next_index(socket.private.data.notebook, section_id, cell_id) do
+            attrs = %{source: source}
+
+            Session.insert_cell(
+              socket.assigns.session.pid,
+              section.id,
+              index,
+              handler.cell_type,
+              attrs
+            )
+
+            {:ok, socket}
+          end
+        end
+      )
+
+    {:noreply, socket}
+  end
+
   @impl true
   def handle_info({:operation, operation}, socket) do
     {:noreply, handle_operation(socket, operation)}
@@ -2164,14 +2210,34 @@ defmodule LivebookWeb.SessionLive do
     end
   end
 
+  defp confirm_setup_default_runtime(socket, reason) do
+    on_confirm = fn socket ->
+      {status, socket} = connect_runtime(socket)
+
+      if status == :ok do
+        Session.queue_cell_evaluation(socket.assigns.session.pid, Cell.setup_cell_id())
+      end
+
+      socket
+    end
+
+    confirm(socket, on_confirm,
+      title: "Setup runtime",
+      description: "#{reason} Do you want to connect and setup the default one?",
+      confirm_text: "Setup runtime",
+      confirm_icon: "play-line",
+      danger: false
+    )
+  end
+
   defp starred_files(starred_notebooks) do
     for info <- starred_notebooks, into: MapSet.new(), do: info.file
   end
 
-  defp code_block_definition_by_name(data, name) do
+  defp example_snippet_definition_by_name(data, name) do
     data.runtime
-    |> Livebook.Runtime.code_block_definitions()
-    |> Enum.find_value(:error, &(&1.name == name && {:ok, &1}))
+    |> Livebook.Runtime.snippet_definitions()
+    |> Enum.find_value(:error, &(&1.type == :example && &1.name == name && {:ok, &1}))
   end
 
   defp smart_cell_definition_by_kind(data, kind) do
@@ -2191,6 +2257,35 @@ defmodule LivebookWeb.SessionLive do
     socket
   end
 
+  defp ensure_packages_then(socket, packages, target_name, target_type, fun) do
+    dependencies = Enum.map(packages, & &1.dependency)
+
+    has_dependencies? =
+      dependencies == [] or
+        Livebook.Runtime.has_dependencies?(socket.private.data.runtime, dependencies)
+
+    cond do
+      has_dependencies? ->
+        case fun.(socket) do
+          {:ok, socket} -> socket
+          :error -> socket
+        end
+
+      Livebook.Runtime.fixed_dependencies?(socket.private.data.runtime) ->
+        put_flash(socket, :error, "This runtime doesn't support adding dependencies")
+
+      true ->
+        on_confirm = fn socket ->
+          case fun.(socket) do
+            {:ok, socket} -> add_dependencies_and_reevaluate(socket, dependencies)
+            :error -> socket
+          end
+        end
+
+        confirm_add_packages(socket, on_confirm, packages, target_name, target_type)
+    end
+  end
+
   defp confirm_add_packages(socket, on_confirm, packages, target_name, target_type) do
     assigns = %{packages: packages, target_name: target_name, target_type: target_type}
 
@@ -2212,24 +2307,6 @@ defmodule LivebookWeb.SessionLive do
     )
   end
 
-  defp insert_code_block_below(socket, variant, section_id, cell_id) do
-    with {:ok, section, index} <-
-           section_with_next_index(socket.private.data.notebook, section_id, cell_id) do
-      attrs = %{source: variant.source}
-      Session.insert_cell(socket.assigns.session.pid, section.id, index, :code, attrs)
-      :ok
-    end
-  end
-
-  defp insert_smart_cell_below(socket, definition, section_id, cell_id) do
-    with {:ok, section, index} <-
-           section_with_next_index(socket.private.data.notebook, section_id, cell_id) do
-      attrs = %{kind: definition.kind}
-      Session.insert_cell(socket.assigns.session.pid, section.id, index, :smart, attrs)
-      :ok
-    end
-  end
-
   defp push_cell_editor_payloads(socket, data, cells, tags \\ :all) do
     for cell <- cells,
         {tag, payload} <- cell_editor_init_payloads(cell, data.cell_infos[cell.id]),
@@ -2299,6 +2376,57 @@ defmodule LivebookWeb.SessionLive do
     end)
   end
 
+  defp find_file_entry(socket, name) do
+    Enum.find(socket.private.data.notebook.file_entries, &(&1.name == name))
+  end
+
+  defp handlers_for_file_entry(file_entry, runtime) do
+    handlers =
+      for definition <- Livebook.Runtime.snippet_definitions(runtime),
+          definition.type == :file_action,
+          do: %{definition: definition, cell_type: :code}
+
+    handlers =
+      if file_entry.type == :attachment do
+        [
+          %{
+            cell_type: :markdown,
+            definition: %{
+              type: :file_action,
+              description: "Insert as Markdown image",
+              source: "![](files/{{NAME}})",
+              file_types: ["image/*"],
+              packages: []
+            }
+          }
+          | handlers
+        ]
+      else
+        handlers
+      end
+
+    handlers
+    |> Enum.filter(&matches_file_types?(file_entry.name, &1.definition.file_types))
+    |> Enum.sort_by(& &1.definition.description)
+  end
+
+  defp matches_file_types?(_name, :any), do: true
+
+  defp matches_file_types?(name, file_types) do
+    mime_type = MIME.from_path(name)
+    extension = Path.extname(name)
+
+    Enum.any?(file_types, fn file_type ->
+      case String.split(file_type, "/") do
+        [group, "*"] ->
+          String.starts_with?(mime_type, group <> "/")
+
+        _ ->
+          file_type == mime_type or file_type == extension
+      end
+    end)
+  end
+
   # Builds view-specific structure of data by cherry-picking
   # only the relevant attributes.
   # We then use `@data_view` in the templates and consequently
@@ -2315,8 +2443,12 @@ defmodule LivebookWeb.SessionLive do
       dirty: data.dirty,
       persistence_warnings: data.persistence_warnings,
       runtime: data.runtime,
-      smart_cell_definitions: data.smart_cell_definitions,
-      code_block_definitions: Livebook.Runtime.code_block_definitions(data.runtime),
+      smart_cell_definitions: Enum.sort_by(data.smart_cell_definitions, & &1.name),
+      example_snippet_definitions:
+        data.runtime
+        |> Livebook.Runtime.snippet_definitions()
+        |> Enum.filter(&(&1.type == :example))
+        |> Enum.sort_by(& &1.name),
       global_status: global_status(data),
       notebook_name: data.notebook.name,
       sections_items:

lib/livebook_web/live/session_live/files_list_component.ex

@@ -45,7 +45,12 @@ defmodule LivebookWeb.SessionLive.FilesListComponent do
               <span class="break-all"><%= file_entry.name %></span>
             </button>
           <% else %>
-            <div class="flex items-center text-gray-500">
+            <div
+              class="flex items-center text-gray-500 cursor-grab"
+              draggable="true"
+              data-el-file-entry
+              data-name={file_entry.name}
+            >
               <.remix_icon icon={file_entry_icon(file_entry.type)} class="text-lg align-middle mr-2" />
               <span class="break-all"><%= file_entry.name %></span>
             </div>

lib/livebook_web/live/session_live/insert_buttons_component.ex

@@ -13,6 +13,15 @@ defmodule LivebookWeb.SessionLive.InsertButtonsComponent do
       aria-label="insert new"
       data-el-insert-buttons
     >
+      <div
+        class="absolute inset-0 h-[30px] z-[100] bg-white rounded-lg border-2 border-dashed border-gray-400"
+        data-el-insert-drop-area
+        data-section-id={@section_id}
+        data-cell-id={@cell_id}
+        id={"cell-#{@id}-dropzone"}
+        phx-hook="Dropzone"
+      >
+      </div>
       <div class={
         "w-full md:absolute z-10 hover:z-[11] #{if(@persistent, do: "opacity-100", else: "opacity-0")} hover:opacity-100 focus-within:opacity-100 flex space-x-2 justify-center items-center"
       }>
@@ -103,25 +112,24 @@ defmodule LivebookWeb.SessionLive.InsertButtonsComponent do
             </button>
           </.menu_item>
           <.menu_item>
-            <.link
-              patch={
-                ~p"/sessions/#{@session_id}/insert-image?section_id=#{@section_id}&cell_id=#{@cell_id || ""}"
-              }
+            <button
+              phx-click="insert_image"
+              phx-value-section_id={@section_id}
+              phx-value-cell_id={@cell_id}
               aria-label="insert image"
               role="menuitem"
             >
               <.remix_icon icon="image-add-line" />
               <span>Image</span>
-            </.link>
+            </button>
           </.menu_item>
-          <%= if @code_block_definitions != [] do %>
+          <%= if @example_snippet_definitions != [] do %>
             <div class="flex items-center mt-4 mb-1 px-5 text-xs text-gray-400 font-light">
               CODE
             </div>
-            <.menu_item :for={definition <- Enum.sort_by(@code_block_definitions, & &1.name)}>
-              <.code_block_insert_button
+            <.menu_item :for={definition <- @example_snippet_definitions}>
+              <.example_snippet_insert_button
                 definition={definition}
-                runtime={@runtime}
                 section_id={@section_id}
                 cell_id={@cell_id}
               />
@@ -149,7 +157,7 @@ defmodule LivebookWeb.SessionLive.InsertButtonsComponent do
               <:toggle>
                 <button class="button-base button-small">+ Smart</button>
               </:toggle>
-              <.menu_item :for={definition <- Enum.sort_by(@smart_cell_definitions, & &1.name)}>
+              <.menu_item :for={definition <- @smart_cell_definitions}>
                 <.smart_cell_insert_button
                   definition={definition}
                   section_id={@section_id}
@@ -163,7 +171,7 @@ defmodule LivebookWeb.SessionLive.InsertButtonsComponent do
     """
   end
 
-  defp code_block_insert_button(assigns) when is_many(assigns.definition.variants) do
+  defp example_snippet_insert_button(assigns) when is_many(assigns.definition.variants) do
     ~H"""
     <.submenu>
       <:primary>
@@ -175,7 +183,7 @@ defmodule LivebookWeb.SessionLive.InsertButtonsComponent do
       <.menu_item :for={{variant, idx} <- Enum.with_index(@definition.variants)}>
         <button
           role="menuitem"
-          phx-click={on_code_block_click(@definition, idx, @runtime, @section_id, @cell_id)}
+          phx-click={on_example_snippet_click(@definition, idx, @section_id, @cell_id)}
         >
           <span><%= variant.name %></span>
         </button>
@@ -184,11 +192,11 @@ defmodule LivebookWeb.SessionLive.InsertButtonsComponent do
     """
   end
 
-  defp code_block_insert_button(assigns) do
+  defp example_snippet_insert_button(assigns) do
     ~H"""
     <button
       role="menuitem"
-      phx-click={on_code_block_click(@definition, 0, @runtime, @section_id, @cell_id)}
+      phx-click={on_example_snippet_click(@definition, 0, @section_id, @cell_id)}
     >
       <.remix_icon icon={@definition.icon} />
       <span><%= @definition.name %></span>
@@ -224,21 +232,15 @@ defmodule LivebookWeb.SessionLive.InsertButtonsComponent do
     """
   end
 
-  defp on_code_block_click(definition, variant_idx, runtime, section_id, cell_id) do
-    if Livebook.Runtime.connected?(runtime) do
-      JS.push("insert_code_block_below",
-        value: %{
-          definition_name: definition.name,
-          variant_idx: variant_idx,
-          section_id: section_id,
-          cell_id: cell_id
-        }
-      )
-    else
-      JS.push("setup_default_runtime",
-        value: %{reason: "To insert this block, you need a connected runtime."}
-      )
-    end
+  defp on_example_snippet_click(definition, variant_idx, section_id, cell_id) do
+    JS.push("insert_example_snippet_below",
+      value: %{
+        definition_name: definition.name,
+        variant_idx: variant_idx,
+        section_id: section_id,
+        cell_id: cell_id
+      }
+    )
   end
 
   defp on_smart_cell_click(definition, section_id, cell_id) do

lib/livebook_web/live/session_live/insert_file_component.ex

@@ -0,0 +1,28 @@
+defmodule LivebookWeb.SessionLive.InsertFileComponent do
+  use LivebookWeb, :live_component
+
+  @impl true
+  def render(assigns) do
+    ~H"""
+    <div class="p-6">
+      <h3 class="text-2xl font-semibold text-gray-800">
+        Insert file
+      </h3>
+      <p class="mt-8 text-gray-700">
+        What do you want to do with the file?
+      </p>
+      <div class="mt-4 w-full flex flex-col space-y-4">
+        <div
+          :for={{handler, idx} <- Enum.with_index(@insert_file_metadata.handlers)}
+          class="px-4 py-3 border border-gray-200 rounded-xl text-gray-800 pointer hover:bg-gray-50 cursor-pointer"
+          phx-click={JS.push("insert_file_action", value: %{idx: idx})}
+        >
+          <span>
+            <%= handler.definition.description %>
+          </span>
+        </div>
+      </div>
+    </div>
+    """
+  end
+end

lib/livebook_web/live/session_live/section_component.ex

@@ -165,7 +165,7 @@ defmodule LivebookWeb.SessionLive.SectionComponent do
             id={"insert-buttons-#{@section_view.id}-first"}
             persistent={@section_view.cell_views == []}
             smart_cell_definitions={@smart_cell_definitions}
-            code_block_definitions={@code_block_definitions}
+            example_snippet_definitions={@example_snippet_definitions}
             runtime={@runtime}
             section_id={@section_view.id}
             cell_id={nil}
@@ -189,7 +189,7 @@ defmodule LivebookWeb.SessionLive.SectionComponent do
               id={"insert-buttons-#{@section_view.id}-#{index}"}
               persistent={false}
               smart_cell_definitions={@smart_cell_definitions}
-              code_block_definitions={@code_block_definitions}
+              example_snippet_definitions={@example_snippet_definitions}
               runtime={@runtime}
               section_id={@section_view.id}
               cell_id={cell_view.id}

lib/livebook_web/router.ex

@@ -92,6 +92,7 @@ defmodule LivebookWeb.Router do
       live "/sessions/:id/export/:tab", SessionLive, :export
       live "/sessions/:id/cell-settings/:cell_id", SessionLive, :cell_settings
       live "/sessions/:id/insert-image", SessionLive, :insert_image
+      live "/sessions/:id/insert-file", SessionLive, :insert_file
       live "/sessions/:id/package-search", SessionLive, :package_search
       get "/sessions/:id/files/:name", SessionController, :show_file
       get "/sessions/:id/images/:name", SessionController, :show_image

test/livebook_web/live/session_live_test.exs

@@ -244,11 +244,13 @@ defmodule LivebookWeb.SessionLiveTest do
       section_id = insert_section(session.pid)
       cell_id = insert_text_cell(session.pid, section_id, :code)
 
-      {:ok, view, _} =
-        live(
-          conn,
-          ~p"/sessions/#{session.id}/insert-image?section_id=#{section_id}&cell_id=#{cell_id}"
-        )
+      {:ok, view, _} = live(conn, ~p"/sessions/#{session.id}")
+
+      view
+      |> element(
+        ~s/[phx-click="insert_image"][phx-value-section_id="#{section_id}"][phx-value-cell_id="#{cell_id}"]/
+      )
+      |> render_click()
 
       view
       |> file_input(~s/#insert-image-modal form/, :image, [
@@ -279,6 +281,87 @@ defmodule LivebookWeb.SessionLiveTest do
                {:ok, "content"}
     end
 
+    test "inserting a file", %{conn: conn, session: session} do
+      section_id = insert_section(session.pid)
+      cell_id = insert_text_cell(session.pid, section_id, :code)
+
+      %{files_dir: files_dir} = session
+      image_file = FileSystem.File.resolve(files_dir, "file.bin")
+      :ok = FileSystem.File.write(image_file, "content")
+      Session.add_file_entries(session.pid, [%{type: :attachment, name: "file.bin"}])
+
+      {:ok, runtime} = Livebook.Runtime.NoopRuntime.new() |> Livebook.Runtime.connect()
+      Session.set_runtime(session.pid, runtime)
+
+      {:ok, view, _} = live(conn, ~p"/sessions/#{session.id}")
+
+      view
+      |> element(~s{[data-el-session]})
+      |> render_hook("insert_file", %{
+        "file_entry_name" => "file.bin",
+        "section_id" => section_id,
+        "cell_id" => cell_id
+      })
+
+      view
+      |> element(~s/#insert-file-modal [phx-click]/, "Read file content")
+      |> render_click()
+
+      assert %{
+               notebook: %{
+                 sections: [
+                   %{
+                     cells: [
+                       _first_cell,
+                       %Cell.Code{
+                         source: """
+                         content =
+                           Kino.FS.file_path("file.bin")
+                           |> File.read!()\
+                         """
+                       }
+                     ]
+                   }
+                 ]
+               }
+             } = Session.get_data(session.pid)
+    end
+
+    test "inserting a file as markdown image", %{conn: conn, session: session} do
+      section_id = insert_section(session.pid)
+      cell_id = insert_text_cell(session.pid, section_id, :code)
+
+      %{files_dir: files_dir} = session
+      image_file = FileSystem.File.resolve(files_dir, "image.jpg")
+      :ok = FileSystem.File.write(image_file, "content")
+      Session.add_file_entries(session.pid, [%{type: :attachment, name: "image.jpg"}])
+
+      {:ok, runtime} = Livebook.Runtime.NoopRuntime.new() |> Livebook.Runtime.connect()
+      Session.set_runtime(session.pid, runtime)
+
+      {:ok, view, _} = live(conn, ~p"/sessions/#{session.id}")
+
+      view
+      |> element(~s{[data-el-session]})
+      |> render_hook("insert_file", %{
+        "file_entry_name" => "image.jpg",
+        "section_id" => section_id,
+        "cell_id" => cell_id
+      })
+
+      view
+      |> element(~s/#insert-file-modal [phx-click]/, "Insert as Markdown image")
+      |> render_click()
+
+      assert %{
+               notebook: %{
+                 sections: [
+                   %{cells: [_first_cell, %Cell.Markdown{source: "![](files/image.jpg)"}]}
+                 ]
+               }
+             } = Session.get_data(session.pid)
+    end
+
     test "deleting section with no cells requires no confirmation",
          %{conn: conn, session: session} do
       section_id = insert_section(session.pid)

test/support/noop_runtime.ex

@@ -55,7 +55,9 @@ defmodule Livebook.Runtime.NoopRuntime do
 
     def has_dependencies?(_runtime, _dependencies), do: true
 
-    def code_block_definitions(_runtime), do: []
+    def snippet_definitions(_runtime) do
+      Livebook.Runtime.Definitions.snippet_definitions()
+    end
 
     def search_packages(_, _, _), do: make_ref()