Merge pull request #3248 from BSd3v/performance-adjust

Adjusting memoization on the `DashWrapper` to be utilized

Author: T4rk1n

@plotly/dash-test-components/src/components/RenderType.js

@@ -0,0 +1,23 @@
+import React, { useState, useEffect } from "react";
+import PropTypes from "prop-types";
+
+const RenderType = (props) => {
+    const onClick = () => {
+        props.setProps({n_clicks: (props.n_clicks || 0) + 1})
+    }
+
+    return <div id={props.id}>
+        <span>{props.dashRenderType}</span>
+        <button onClick={onClick}>Test Internal</button>
+    </div>;
+};
+
+RenderType.propTypes = {
+    id: PropTypes.string,
+    dashRenderType: PropTypes.string,
+    n_clicks: PropTypes.number,
+    setProps: PropTypes.func
+};
+
+RenderType.dashRenderType = true;
+export default RenderType;

@plotly/dash-test-components/src/index.js

@@ -7,6 +7,7 @@ import MyPersistedComponentNested from './components/MyPersistedComponentNested'
 import StyledComponent from './components/StyledComponent';
 import WidthComponent from './components/WidthComponent';
 import ComponentAsProp from './components/ComponentAsProp';
+import RenderType from './components/RenderType';
 
 import DrawCounter from './components/DrawCounter';
 import AddPropsComponent from "./components/AddPropsComponent";
@@ -32,4 +33,5 @@ export {
     ShapeOrExactKeepOrderComponent,
     ArrayOfExactOrShapeWithNodePropAssignNone,
     ExternalComponent,
+    RenderType
 };

CHANGELOG.md

@@ -6,10 +6,17 @@ This project adheres to [Semantic Versioning](https://semver.org/).
 
 ## Changed
 - [#3113](https://github.com/plotly/dash/pull/3113) Adjusted background polling requests to strip the data from the request, this allows for context to flow as normal. This addresses issue [#3111](https://github.com/plotly/dash/pull/3111)
+- [#3248](https://github.com/plotly/dash/pull/3248) Changes to rendering logic:
+  - if it is first time rendering, render from the parent props
+  - listens only to updates for that single component, no children listening to parents
+  - if parents change a prop with components as props, only the prop changed re-renders, this is then forced on all children regardless of whether or not the props changed
 
 ## Fixed
 - [#3251](https://github.com/plotly/dash/pull/3251). Prevented default styles from overriding `className_*` props in `dcc.Upload` component.
 
+## Added
+- [#3248](https://github.com/plotly/dash/pull/3248) added new `dashRenderType` to determine why the component layout was changed (`internal`, `callback`, `parent`, `clientsideApi`):
+    - this can be utilized to keep from rendering components by the component having `dashRenderType` defined as a prop, and the `dashRenderType = true` must be set on the component, eg (`Div.dashRenderType = true`)
 
 ## [3.0.1] - 2025-03-24
 

dash/dash-renderer/src/actions/callbacks.ts

@@ -360,7 +360,8 @@ function updateComponent(component_id: any, props: any, cb: ICallbackPayload) {
         dispatch(
             updateProps({
                 props,
-                itempath: componentPath
+                itempath: componentPath,
+                renderType: 'callback'
             })
         );
         dispatch(notifyObservers({id: component_id, props}));

dash/dash-renderer/src/observers/executedCallbacks.ts

@@ -63,12 +63,12 @@ const observer: IStoreObserverDefinition<IStoreState> = {
             // In case the update contains whole components, see if any of
             // those components have props to update to persist user edits.
             const {props} = applyPersistence({props: updatedProps}, dispatch);
-
             dispatch(
                 updateProps({
                     itempath,
                     props,
-                    source: 'response'
+                    source: 'response',
+                    renderType: 'callback'
                 })
             );
 

dash/dash-renderer/src/reducers/reducer.js

@@ -27,7 +27,7 @@ export const apiRequests = [
     'loginRequest'
 ];
 
-function layoutHashes(state = {}, action) {
+const layoutHashes = (state = {}, action) => {
     if (
         includes(action.type, [
             'UNDO_PROP_CHANGE',
@@ -37,12 +37,21 @@ function layoutHashes(state = {}, action) {
     ) {
         // Let us compare the paths sums to get updates without triggering
         // render on the parent containers.
-        const strPath = stringifyPath(action.payload.itempath);
-        const prev = pathOr(0, [strPath], state);
-        return assoc(strPath, prev + 1, state);
+        const actionPath = action.payload.itempath;
+        const strPath = stringifyPath(actionPath);
+        const prev = pathOr(0, [strPath, 'hash'], state);
+        state = assoc(
+            strPath,
+            {
+                hash: prev + 1,
+                changedProps: action.payload.props,
+                renderType: action.payload.renderType
+            },
+            state
+        );
     }
     return state;
-}
+};
 
 function mainReducer() {
     const parts = {

dash/dash-renderer/src/utils/clientsideFunctions.ts

@@ -16,16 +16,17 @@ function set_props(
     for (let y = 0; y < ds.length; y++) {
         const {dispatch, getState} = ds[y];
         let componentPath;
+        const {paths} = getState();
         if (!Array.isArray(idOrPath)) {
-            const {paths} = getState();
             componentPath = getPath(paths, idOrPath);
         } else {
             componentPath = idOrPath;
         }
         dispatch(
             updateProps({
                 props,
-                itempath: componentPath
+                itempath: componentPath,
+                renderType: 'clientsideApi'
             })
         );
         dispatch(notifyObservers({id: idOrPath, props}));