Allow dropping external files into the notebook

assets/css/js_interop.css

@@ -77,6 +77,10 @@ solely client-side operations.
   @apply hidden;
 }
 
+[data-el-session]:not([data-js-dragging="external"]) [data-el-files-drop-area] {
+  @apply hidden;
+}
+
 [data-el-cell][data-js-focused] {
   @apply border-blue-300 border-opacity-100;
 }

assets/js/hooks/session.js

@@ -713,72 +713,135 @@ const Session = {
    * Initializes drag and drop event handlers.
    */
   initializeDragAndDrop() {
+    let isDragging = false;
     let draggedEl = null;
+    let files = null;
+
+    const startDragging = (element = null) => {
+      if (!isDragging) {
+        isDragging = true;
+        draggedEl = element;
+
+        const type = element ? "internal" : "external";
+        this.el.setAttribute("data-js-dragging", type);
+
+        if (type === "external") {
+          this.toggleFilesList(true);
+        }
+      }
+    };
+
+    const stopDragging = () => {
+      if (isDragging) {
+        isDragging = false;
+        this.el.removeAttribute("data-js-dragging");
+      }
+    };
 
     this.el.addEventListener("dragstart", (event) => {
-      draggedEl = event.target;
-      this.el.setAttribute("data-js-dragging", "");
+      startDragging(event.target);
     });
 
-    this.el.addEventListener("dragend", (event) => {
-      this.el.removeAttribute("data-js-dragging");
+    this.el.addEventListener("dragenter", (event) => {
+      startDragging();
+    });
+
+    this.el.addEventListener("dragleave", (event) => {
+      if (!this.el.contains(event.relatedTarget)) {
+        stopDragging();
+      }
     });
 
     this.el.addEventListener("dragover", (event) => {
-      const dropEl = event.target.closest(`[data-el-insert-drop-area]`);
+      event.stopPropagation();
+      event.preventDefault();
+    });
+
+    this.el.addEventListener("drop", (event) => {
+      event.stopPropagation();
+      event.preventDefault();
+
+      const insertDropEl = event.target.closest(`[data-el-insert-drop-area]`);
+      const filesDropEl = event.target.closest(`[data-el-files-drop-area]`);
+
+      if (insertDropEl) {
+        const sectionId = insertDropEl.getAttribute("data-section-id") || null;
+        const cellId = insertDropEl.getAttribute("data-cell-id") || null;
+
+        if (event.dataTransfer.files.length > 0) {
+          files = event.dataTransfer.files;
 
-      if (dropEl) {
-        event.preventDefault();
+          this.pushEvent("handle_file_drop", {
+            section_id: sectionId,
+            cell_id: cellId,
+          });
+        } else if (draggedEl && draggedEl.matches("[data-el-file-entry]")) {
+          const fileEntryName = draggedEl.getAttribute("data-name");
+
+          this.pushEvent("insert_file", {
+            file_entry_name: fileEntryName,
+            section_id: sectionId,
+            cell_id: cellId,
+          });
+        }
+      } else if (filesDropEl) {
+        if (event.dataTransfer.files.length > 0) {
+          files = event.dataTransfer.files;
+          this.pushEvent("handle_file_drop", {});
+        }
       }
+
+      stopDragging();
     });
 
-    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,
-        });
+    this.handleEvent("finish_file_drop", (event) => {
+      const inputEl = document.querySelector(
+        `#add-file-entry-modal input[type="file"]`
+      );
+
+      if (inputEl) {
+        inputEl.files = files;
+        inputEl.dispatchEvent(new Event("change", { bubbles: true }));
       }
     });
   },
 
   // User action handlers (mostly keybindings)
 
-  toggleSectionsList() {
-    this.toggleSidePanelContent("sections-list");
+  toggleSectionsList(force = null) {
+    this.toggleSidePanelContent("sections-list", force);
   },
 
-  toggleClientsList() {
-    this.toggleSidePanelContent("clients-list");
+  toggleClientsList(force = null) {
+    this.toggleSidePanelContent("clients-list", force);
   },
 
-  toggleSecretsList() {
-    this.toggleSidePanelContent("secrets-list");
+  toggleSecretsList(force = null) {
+    this.toggleSidePanelContent("secrets-list", force);
   },
 
-  toggleAppInfo() {
-    this.toggleSidePanelContent("app-info");
+  toggleAppInfo(force = null) {
+    this.toggleSidePanelContent("app-info", force);
   },
 
-  toggleFilesList() {
-    this.toggleSidePanelContent("files-list");
+  toggleFilesList(force = null) {
+    this.toggleSidePanelContent("files-list", force);
   },
 
-  toggleRuntimeInfo() {
-    this.toggleSidePanelContent("runtime-info");
+  toggleRuntimeInfo(force = null) {
+    this.toggleSidePanelContent("runtime-info", force);
   },
 
-  toggleSidePanelContent(name) {
-    if (this.el.getAttribute("data-js-side-panel-content") === name) {
-      this.el.removeAttribute("data-js-side-panel-content");
-    } else {
+  toggleSidePanelContent(name, force = null) {
+    const shouldOpen =
+      force === null
+        ? this.el.getAttribute("data-js-side-panel-content") !== name
+        : force;
+
+    if (shouldOpen) {
       this.el.setAttribute("data-js-side-panel-content", name);
+    } else {
+      this.el.removeAttribute("data-js-side-panel-content");
     }
   },
 

lib/livebook_web/components/form_components.ex

@@ -588,7 +588,7 @@ defmodule LivebookWeb.FormComponents do
         for={@upload.ref}
         phx-drop-target={@upload.ref}
       >
-        <span name="placeholder" class="font-medium text-gray-400">
+        <span class="font-medium text-gray-400">
           Click to select a file or drag a local file here
         </span>
       </label>

lib/livebook_web/live/session_live.ex

@@ -965,11 +965,18 @@ defmodule LivebookWeb.SessionLive do
     {:noreply, handle_relative_path(socket, path, requested_url)}
   end
 
-  def handle_params(%{"tab" => tab}, _url, socket)
-      when socket.assigns.live_action in [:export, :add_file_entry] do
+  def handle_params(%{"tab" => tab}, _url, socket) when socket.assigns.live_action == :export do
     {:noreply, assign(socket, tab: tab)}
   end
 
+  def handle_params(%{"tab" => tab} = params, _url, socket)
+      when socket.assigns.live_action == :add_file_entry do
+    file_drop_metadata =
+      if(params["file_drop"] == "true", do: socket.assigns[:file_drop_metadata])
+
+    {:noreply, assign(socket, tab: tab, file_drop_metadata: file_drop_metadata)}
+  end
+
   def handle_params(params, _url, socket)
       when socket.assigns.live_action == :secrets do
     socket =
@@ -1579,6 +1586,33 @@ defmodule LivebookWeb.SessionLive do
     {:noreply, socket}
   end
 
+  def handle_event(
+        "handle_file_drop",
+        %{"section_id" => section_id, "cell_id" => cell_id},
+        socket
+      ) do
+    if Livebook.Runtime.connected?(socket.private.data.runtime) do
+      {:noreply,
+       socket
+       |> assign(file_drop_metadata: %{section_id: section_id, cell_id: cell_id})
+       |> push_patch(
+         to: ~p"/sessions/#{socket.assigns.session.id}/add-file/upload?file_drop=true"
+       )
+       |> push_event("finish_file_drop", %{})}
+    else
+      reason = "To see the available options, you need a connected runtime."
+      {:noreply, confirm_setup_default_runtime(socket, reason)}
+    end
+  end
+
+  def handle_event("handle_file_drop", %{}, socket) do
+    {:noreply,
+     socket
+     |> assign(file_drop_metadata: nil)
+     |> push_patch(to: ~p"/sessions/#{socket.assigns.session.id}/add-file/upload?file_drop=true")
+     |> push_event("finish_file_drop", %{})}
+  end
+
   @impl true
   def handle_info({:operation, operation}, socket) do
     {:noreply, handle_operation(socket, operation)}
@@ -1683,6 +1717,26 @@ defmodule LivebookWeb.SessionLive do
     {:noreply, insert_cell_below(socket, params)}
   end
 
+  def handle_info({:file_entry_uploaded, file_entry}, socket) do
+    case socket.assigns.file_drop_metadata do
+      %{section_id: section_id, cell_id: cell_id} ->
+        {: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")}
+
+      nil ->
+        {:noreply, socket}
+    end
+  end
+
   def handle_info({:push_patch, to}, socket) do
     {:noreply, push_patch(socket, to: to)}
   end

lib/livebook_web/live/session_live/add_file_entry_upload_component.ex

@@ -44,7 +44,13 @@ defmodule LivebookWeb.SessionLive.AddFileEntryUploadComponent do
             label="File"
             on_clear={JS.push("clear_file", target: @myself)}
           />
-          <.text_field field={f[:name]} label="Name" autocomplete="off" phx-debounce="blur" />
+          <.text_field
+            field={f[:name]}
+            label="Name"
+            id="add-file-entry-form-name"
+            autocomplete="off"
+            phx-debounce="blur"
+          />
         </div>
         <div class="mt-6 flex space-x-3">
           <button
@@ -67,13 +73,21 @@ defmodule LivebookWeb.SessionLive.AddFileEntryUploadComponent do
   def handle_event("validate", %{"data" => data} = params, socket) do
     upload_entries = socket.assigns.uploads.file.entries
 
-    data =
+    {data, socket} =
       case {params["_target"], data["name"], upload_entries} do
         {["file"], "", [entry]} ->
-          %{data | "name" => entry.client_name}
+          # Emulate input event to make sure validation errors are shown
+          socket =
+            exec_js(
+              socket,
+              JS.dispatch("input", to: "#add-file-entry-form-name")
+              |> JS.dispatch("blur", to: "#add-file-entry-form-name")
+            )
+
+          {%{data | "name" => entry.client_name}, socket}
 
         _ ->
-          data
+          {data, socket}
       end
 
     changeset = data |> changeset() |> Map.replace!(:action, :validate)
@@ -108,6 +122,7 @@ defmodule LivebookWeb.SessionLive.AddFileEntryUploadComponent do
           :ok ->
             file_entry = %{name: data.name, type: :attachment}
             Livebook.Session.add_file_entries(socket.assigns.session.pid, [file_entry])
+            send(self(), {:file_entry_uploaded, file_entry})
             {:noreply, push_patch(socket, to: ~p"/sessions/#{socket.assigns.session.id}")}
 
           {:error, message} ->

lib/livebook_web/live/session_live/files_list_component.ex

@@ -30,6 +30,16 @@ defmodule LivebookWeb.SessionLive.FilesListComponent do
         </h3>
         <.files_info_icon />
       </div>
+      <div
+        class="mt-5 h-20 rounded-lg border-2 border-dashed border-gray-400 flex items-center justify-center"
+        data-el-files-drop-area
+        id="files-dropzone"
+        phx-hook="Dropzone"
+      >
+        <span class="font-medium text-gray-400">
+          Add to files
+        </span>
+      </div>
       <div class="mt-5 flex flex-col gap-1">
         <div
           :for={{file_entry, idx} <- Enum.with_index(@file_entries)}

lib/livebook_web/live/session_live/insert_file_component.ex

@@ -6,12 +6,12 @@ defmodule LivebookWeb.SessionLive.InsertFileComponent do
     ~H"""
     <div class="p-6">
       <h3 class="text-2xl font-semibold text-gray-800">
-        Insert file
+        Suggested actions
       </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 class="mt-8 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"

lib/livebook_web/live/session_live/insert_image_component.ex

@@ -56,7 +56,13 @@ defmodule LivebookWeb.SessionLive.InsertImageComponent do
             label="File"
             on_clear={JS.push("clear_file", target: @myself)}
           />
-          <.text_field field={f[:name]} label="Name" autocomplete="off" phx-debounce="blur" />
+          <.text_field
+            field={f[:name]}
+            label="Name"
+            id="insert-image-form-name"
+            autocomplete="off"
+            phx-debounce="blur"
+          />
         </div>
         <div class="mt-8 flex justify-end space-x-2">
           <.link patch={@return_to} class="button-base button-outlined-gray">
@@ -79,13 +85,21 @@ defmodule LivebookWeb.SessionLive.InsertImageComponent do
   def handle_event("validate", %{"data" => data} = params, socket) do
     upload_entries = socket.assigns.uploads.image.entries
 
-    data =
+    {data, socket} =
       case {params["_target"], data["name"], upload_entries} do
         {["image"], "", [entry]} ->
-          %{data | "name" => entry.client_name}
+          # Emulate input event to make sure validation errors are shown
+          socket =
+            exec_js(
+              socket,
+              JS.dispatch("input", to: "#insert-image-form-name")
+              |> JS.dispatch("blur", to: "#insert-image-form-name")
+            )
+
+          {%{data | "name" => entry.client_name}, socket}
 
         _ ->
-          data
+          {data, socket}
       end
 
     changeset = data |> changeset() |> Map.replace!(:action, :validate)