feat: Create Session.set_message_handler(name, handler) (#1253)

Author: schloerke

CHANGELOG.md

@@ -15,6 +15,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### New features
 
+* `Session` objects now have a `set_message_handler(name, fn)` method that allows you to register a message handler function that will be called when a request message with the given name is received from the client (via `Shiny.shinyapp.makeRequest()` (JS)). (#1253)
+
 * Experimental: `@render.data_frame` return values of `DataTable` and `DataGrid` support `mode="edit"` to enable editing of the data table cells. (#1198)
 
 * `ui.card()` and `ui.value_box()` now take an `id` argument that, when provided, is used to report the full screen state of the card or value box to the server. For example, when using `ui.card(id = "my_card", full_screen = TRUE)` you can determine if the card is currently in full screen mode by reading the boolean value of `input.my_card()["full_screen"]`. (#1215)

js/dataframe/cell.tsx

@@ -20,6 +20,7 @@ import {
   getCellEditMapValue,
 } from "./cell-edit-map";
 import { updateCellsData } from "./data-update";
+import type { PatchInfo } from "./types";
 
 // States
 // # √ Ready
@@ -50,6 +51,7 @@ export type CellState = keyof typeof CellStateEnum;
 interface TableBodyCellProps {
   id: string | null;
   cell: Cell<unknown[], unknown>;
+  patchInfo: PatchInfo;
   columns: readonly string[];
   editCellsIsAllowed: boolean;
   editRowIndex: number | null;
@@ -66,6 +68,7 @@ interface TableBodyCellProps {
 export const TableBodyCell: FC<TableBodyCellProps> = ({
   id,
   cell,
+  patchInfo,
   columns,
   editCellsIsAllowed,
   editRowIndex,
@@ -137,7 +140,7 @@ export const TableBodyCell: FC<TableBodyCellProps> = ({
   //   * When a td is focused, Have esc key move focus to the table
   //   * When table is focused, Have esc key blur the focus
   // TODO-barret-future; Combat edit mode being independent of selection mode
-  // * In row / column selection mode, allow for arrowoutput_binding_request_handler key navigation by focusing on a single cell, not a TR
+  // * In row / column selection mode, allow for arrow key navigation by focusing on a single cell, not a TR
   // * If a cell is focused,
   //   * `enter key` allows you to go into edit mode; If editing is turned off, the selection is toggled
   //   * `space key` allows you toggle the selection of the cell
@@ -253,6 +256,7 @@ export const TableBodyCell: FC<TableBodyCellProps> = ({
     // updateCellsData updates the underlying data via `setData` and `setCellEditMap`
     updateCellsData({
       id,
+      patchInfo: patchInfo,
       patches: [
         {
           rowIndex,
@@ -273,6 +277,7 @@ export const TableBodyCell: FC<TableBodyCellProps> = ({
     });
   }, [
     id,
+    patchInfo,
     rowIndex,
     columnIndex,
     value,

js/dataframe/data-update.tsx

@@ -3,6 +3,7 @@ import { ResponseValue, makeRequestPromise } from "./request";
 import type { CellState } from "./cell";
 import { CellStateEnum } from "./cell";
 import { CellEdit, SetCellEditMap, makeCellEditMapKey } from "./cell-edit-map";
+import type { PatchInfo } from "./types";
 
 export type CellPatch = {
   rowIndex: number;
@@ -19,6 +20,7 @@ export type CellPatchPy = {
 
 export function updateCellsData({
   id,
+  patchInfo,
   patches,
   onSuccess,
   onError,
@@ -27,6 +29,7 @@ export function updateCellsData({
   setCellEditMap,
 }: {
   id: string | null;
+  patchInfo: PatchInfo;
   patches: CellPatch[];
   onSuccess: (values: CellPatch[]) => void;
   onError: (err: string) => void;
@@ -47,12 +50,8 @@ export function updateCellsData({
   });
 
   makeRequestPromise({
-    method: "output_binding_request_handler",
+    method: patchInfo.key,
     args: [
-      // id: string
-      id,
-      // handler: string
-      "patches",
       // list[CellPatch]
       patchesPy,
     ],

js/dataframe/index.tsx

@@ -37,7 +37,7 @@ import { SortArrow } from "./sort-arrows";
 import css from "./styles.scss";
 import { useTabindexGroup } from "./tabindex-group";
 import { useSummary } from "./table-summary";
-import { EditModeEnum, PandasData, TypeHint } from "./types";
+import { EditModeEnum, PandasData, PatchInfo, TypeHint } from "./types";
 
 // TODO-barret; Type support
 // export interface PandasData<TIndex> {
@@ -87,11 +87,16 @@ declare module "@tanstack/table-core" {
 interface ShinyDataGridProps<TIndex> {
   id: string | null;
   data: PandasData<TIndex>;
+  patchInfo: PatchInfo;
   bgcolor?: string;
 }
 
-const ShinyDataGrid: FC<ShinyDataGridProps<unknown>> = (props) => {
-  const { id, data, bgcolor } = props;
+const ShinyDataGrid: FC<ShinyDataGridProps<unknown>> = ({
+  id,
+  data,
+  patchInfo,
+  bgcolor,
+}) => {
   const { columns, type_hints: typeHints, data: rowData } = data;
   const { width, height, fill, filters: withFilters } = data.options;
 
@@ -458,6 +463,7 @@ const ShinyDataGrid: FC<ShinyDataGridProps<unknown>> = (props) => {
                           id={id}
                           key={cell.id}
                           cell={cell}
+                          patchInfo={patchInfo}
                           editCellsIsAllowed={editCellsIsAllowed}
                           columns={columns}
                           editRowIndex={editRowIndex}
@@ -645,10 +651,12 @@ export class ShinyDataFrameOutput extends HTMLElement {
     }
   }
 
-  renderValue(data: unknown) {
+  renderValue(
+    value: null | { patchInfo: PatchInfo; data: PandasData<unknown> }
+  ) {
     this.clearError();
 
-    if (!data) {
+    if (!value) {
       this.reactRoot!.render(null);
       return;
     }
@@ -657,7 +665,8 @@ export class ShinyDataFrameOutput extends HTMLElement {
       <StrictMode>
         <ShinyDataGrid
           id={this.id}
-          data={data as PandasData<unknown>}
+          data={value.data}
+          patchInfo={value.patchInfo}
           bgcolor={getComputedBgColor(this)}
         ></ShinyDataGrid>
       </StrictMode>

js/dataframe/types.ts

@@ -34,3 +34,7 @@ export interface PandasData<TIndex> {
   type_hints?: ReadonlyArray<TypeHint>;
   options: DataGridOptions;
 }
+
+export interface PatchInfo {
+  key: string;
+}

shiny/render/_dataframe.py

@@ -5,6 +5,8 @@
 from typing import (
     TYPE_CHECKING,
     Any,
+    Awaitable,
+    Callable,
     Literal,
     Optional,
     Protocol,
@@ -23,7 +25,7 @@
 from .._typing_extensions import Self
 from ..session._utils import get_current_session, require_active_session
 from ._dataframe_unsafe import serialize_numpy_dtypes
-from .renderer import Jsonifiable, Renderer, ValueFn, output_binding_request_handler
+from .renderer import Jsonifiable, Renderer, ValueFn
 from .renderer._utils import JsonifiableDict
 
 if TYPE_CHECKING:
@@ -618,19 +620,31 @@ async def patches_fn(
 
         self.set_patch_fn(patch_fn)
         self.set_patches_fn(patches_fn)
-        # self._add_message_handlers()
 
-        # # TODO-barret; Use dynamic route instead of message handlers? Gut all of `output_binding_request_handler?` TODO: Talk with Joe
-        # session = get_current_session()
-        # if session is not None:
-        #     session.dynamic_route("data-frame-patches-{id}", self._handle_patches)
+    def _set_patches_handler_impl(
+        self,
+        handler: Callable[..., Awaitable[Jsonifiable]] | None,
+    ) -> str:
+        session = self._get_session()
+        key = session.set_message_handler(
+            f"data_frame_patches_{self.output_id}",
+            handler,
+        )
+        return key
+
+    def _reset_patches_handler(self) -> str:
+        return self._set_patches_handler_impl(None)
 
-        # output_binding_request_handler(session, "name", self._handle_patches_1)
+    def _set_patches_handler(self) -> str:
+        """
+        Set the client patches handler for the data frame.
+
+        This method **must be** called as late as possible as it depends on the ID of the output.
+        """
+        return self._set_patches_handler_impl(self._patches_handler)
 
-    # To be called by session's output_binding_request_handler message handler on this data_frame instance
-    @output_binding_request_handler
     # Do not change this method name unless you update corresponding code in `/js/dataframe/`!!
-    async def _handle_patches(self, patches: list[CellPatch]) -> Jsonifiable:
+    async def _patches_handler(self, patches: list[CellPatch]) -> Jsonifiable:
         # TODO-barret; verify that the patches are in the correct format
 
         # Call user's cell update method to retrieve formatted values
@@ -713,6 +727,7 @@ def _set_output_metadata(self, *, output_id: str) -> None:
     async def render(self) -> Jsonifiable:
         # Reset value
         self._reset_reactives()
+        self._reset_patches_handler()
 
         value = await self.fn()
         if value is None:
@@ -726,8 +741,15 @@ async def render(self) -> Jsonifiable:
                 )
             )
 
+        # Send info to client
+        patch_key = self._set_patches_handler()
         self._value.set(value)
-        return value.to_payload()
+        return {
+            "data": value.to_payload(),
+            "patchInfo": {
+                "key": patch_key,
+            },
+        }
 
     async def _send_message_to_browser(self, handler: str, obj: dict[str, Any]):
 

shiny/render/renderer/__init__.py

@@ -1,5 +1,4 @@
-from ._dispatch import output_binding_request_handler
-from ._renderer import (  # noqa: F401
+from ._renderer import (
     AsyncValueFn,
     Jsonifiable,
     Renderer,
@@ -13,5 +12,4 @@
     "Jsonifiable",
     "AsyncValueFn",
     "RendererT",
-    "output_binding_request_handler",
 )