[JSS 12][React sample] Race condition, under load React app may rende…

…r HTML from a different route (#454)

samples/react/server/server.js

@@ -7,7 +7,6 @@ import GraphQLClientFactory from '../src/lib/GraphQLClientFactory';
 import config from '../src/temp/config';
 import i18ninit from '../src/i18n';
 import AppRoot, { routePatterns } from '../src/AppRoot';
-import { setServerSideRenderingState } from '../src/RouteHandler';
 import { getHtmlTemplate } from './htmlTemplateFactory';
 
 /** Asserts that a string replace actually replaced something */
@@ -45,7 +44,6 @@ export const appName = config.jssAppName;
 export function renderView(callback, path, data, viewBag) {
   try {
     const state = parseServerData(data, viewBag);
-    setServerSideRenderingState(state);
 
     /*
       GraphQL Data
@@ -64,7 +62,12 @@ export function renderView(callback, path, data, viewBag) {
         // is included in the SSR'ed markup instead of whatever the 'loading' state is.
         // Not using GraphQL? Use ReactDOMServer.renderToString() instead.
         renderToStringWithData(
-          <AppRoot path={path} Router={StaticRouter} graphQLClient={graphQLClient} />
+          <AppRoot
+            path={path}
+            Router={StaticRouter}
+            graphQLClient={graphQLClient}
+            ssrState={state}
+          />
         )
       )
       .then((renderedAppHtml) =>

samples/react/src/AppRoot.js

@@ -1,9 +1,8 @@
 import React from 'react';
-import { SitecoreContext } from '@sitecore-jss/sitecore-jss-react';
+import { SitecoreContext, SitecoreContextFactory } from '@sitecore-jss/sitecore-jss-react';
 import { Route, Switch } from 'react-router-dom';
 import { ApolloProvider } from 'react-apollo';
 import componentFactory from './temp/componentFactory';
-import SitecoreContextFactory from './lib/SitecoreContextFactory';
 import RouteHandler from './RouteHandler';
 
 // This is the main JSX entry point of the app invoked by the renderer (server or client rendering).
@@ -22,21 +21,53 @@ export const routePatterns = [
 //    Not needed if not using connected GraphQL.
 // SitecoreContext: provides component resolution and context services via withSitecoreContext
 // Router: provides a basic routing setup that will resolve Sitecore item routes and allow for language URL prefixes.
-const AppRoot = ({ path, Router, graphQLClient }) => {
-  const routeRenderFunction = (props) => <RouteHandler route={props} />;
-  return (
-    <ApolloProvider client={graphQLClient}>
-      <SitecoreContext componentFactory={componentFactory} contextFactory={SitecoreContextFactory}>
-        <Router location={path} context={{}}>
-          <Switch>
-            {routePatterns.map((routePattern) => (
-              <Route key={routePattern} path={routePattern} render={routeRenderFunction} />
-            ))}
-          </Switch>
-        </Router>
-      </SitecoreContext>
-    </ApolloProvider>
-  );
-};
+
+class AppRoot extends React.Component {
+  state = {
+    ssrRenderComplete: false,
+    contextFactory: new SitecoreContextFactory()
+  }
+
+  setSsrRenderComplete = ssrRenderComplete => {
+    this.setState({
+      ssrRenderComplete
+    })
+  }
+
+  render() {
+    const { path, Router, graphQLClient, ssrState } = this.props;
+
+    if (ssrState && ssrState.sitecore && ssrState.sitecore.route) {
+      // set the initial sitecore context data if we got SSR initial state
+      this.state.contextFactory.setSitecoreContext({
+        route: ssrState.sitecore.route,
+        itemId: ssrState.sitecore.route.itemId,
+        ...ssrState.sitecore.context,
+      });
+    }
+
+    const routeRenderFunction = (props) => 
+      <RouteHandler 
+        route={props}
+        ssrState={this.state.ssrRenderComplete ? null : ssrState}
+        contextFactory={this.state.contextFactory}
+        setSsrRenderComplete={this.setSsrRenderComplete}
+        ssrRenderComplete={this.state.ssrRenderComplete}
+      />;
+    return (
+      <ApolloProvider client={graphQLClient}>
+        <SitecoreContext componentFactory={componentFactory} contextFactory={this.state.contextFactory}>
+          <Router location={path} context={{}}>
+            <Switch>
+              {routePatterns.map((routePattern) => (
+                <Route key={routePattern} path={routePattern} render={routeRenderFunction} />
+              ))}
+            </Switch>
+          </Router>
+        </SitecoreContext>
+      </ApolloProvider>
+    );
+  }
+}
 
 export default AppRoot;

samples/react/src/RouteHandler.js

@@ -2,7 +2,6 @@ import React from 'react';
 import i18n from 'i18next';
 import Helmet from 'react-helmet';
 import { isExperienceEditorActive, dataApi } from '@sitecore-jss/sitecore-jss-react';
-import SitecoreContextFactory from './lib/SitecoreContextFactory';
 import { dataFetcher } from './dataFetcher';
 import config from './temp/config';
 import Layout from './Layout';
@@ -14,27 +13,18 @@ import NotFound from './NotFound';
 // So react-router delegates all route rendering to this handler, which attempts to get the right
 // route data from Sitecore - and if none exists, renders the not found component.
 
-let ssrInitialState = null;
-
 export default class RouteHandler extends React.Component {
   constructor(props) {
     super(props);
 
+    const ssrInitialState = props.ssrState;
+
     this.state = {
       notFound: true,
       routeData: ssrInitialState, // null when client-side rendering
       defaultLanguage: config.defaultLanguage,
     };
 
-    if (ssrInitialState && ssrInitialState.sitecore && ssrInitialState.sitecore.route) {
-      // set the initial sitecore context data if we got SSR initial state
-      SitecoreContextFactory.setSitecoreContext({
-        route: ssrInitialState.sitecore.route,
-        itemId: ssrInitialState.sitecore.route.itemId,
-        ...ssrInitialState.sitecore.context,
-      });
-    }
-
     // route data from react-router - if route was resolved, it's not a 404
     if (props.route !== null) {
       this.state.notFound = false;
@@ -53,17 +43,6 @@ export default class RouteHandler extends React.Component {
       this.state.defaultLanguage = ssrInitialState.context.language;
     }
 
-    // once we initialize the route handler, we've "used up" the SSR data,
-    // if it existed, so we want to clear it now that it's in react state.
-    // future route changes that might destroy/remount this component should ignore any SSR data.
-    // EXCEPTION: Unless we are still SSR-ing. Because SSR can re-render the component twice
-    // (once to find GraphQL queries that need to run, the second time to refresh the view with
-    // GraphQL query results)
-    // We test for SSR by checking for Node-specific process.env variable.
-    if (typeof window !== 'undefined') {
-      ssrInitialState = null;
-    }
-
     this.componentIsMounted = false;
     this.languageIsChanging = false;
 
@@ -72,6 +51,17 @@ export default class RouteHandler extends React.Component {
   }
 
   componentDidMount() {
+    // once we initialize the route handler, we've "used up" the SSR data,	
+    // if it existed, so we want to clear it now that it's in react state.	
+    // future route changes that might destroy/remount this component should ignore any SSR data.	
+    // EXCEPTION: Unless we are still SSR-ing. Because SSR can re-render the component twice	
+    // (once to find GraphQL queries that need to run, the second time to refresh the view with	
+    // GraphQL query results)	
+    // We test for SSR by checking for Node-specific process.env variable.	
+    if (typeof window !== "undefined" && !this.props.ssrRenderComplete && this.props.setSsrRenderComplete) {
+      this.props.setSsrRenderComplete(true);
+    }
+
     // if no existing routeData is present (from SSR), get Layout Service fetching the route data
     if (!this.state.routeData) {
       this.updateRouteData();
@@ -99,7 +89,7 @@ export default class RouteHandler extends React.Component {
     getRouteData(sitecoreRoutePath, language).then((routeData) => {
       if (routeData !== null && routeData.sitecore && routeData.sitecore.route) {
         // set the sitecore context data and push the new route
-        SitecoreContextFactory.setSitecoreContext({
+        this.props.contextFactory.setSitecoreContext({
           route: routeData.sitecore.route,
           itemId: routeData.sitecore.route.itemId,
           ...routeData.sitecore.context,
@@ -183,15 +173,6 @@ export default class RouteHandler extends React.Component {
   }
 }
 
-/**
- * Sets the initial state provided by server-side rendering.
- * Setting this state will bypass initial route data fetch calls.
- * @param {object} ssrState
- */
-export function setServerSideRenderingState(ssrState) {
-  ssrInitialState = ssrState;
-}
-
 /**
  * Gets route data from Sitecore. This data is used to construct the component layout for a JSS route.
  * @param {string} route Route path to get data for (e.g. /about)

samples/react/src/components/ContentBlock/index.js

@@ -1,22 +1,17 @@
 import React from 'react';
-import { RichText, withSitecoreContext } from '@sitecore-jss/sitecore-jss-react';
+import { Text, RichText } from '@sitecore-jss/sitecore-jss-react';
 
 /**
  * A simple Content Block component, with a heading and rich text block.
  * This is the most basic building block of a content site, and the most basic
  * JSS component that's useful.
  */
-const ContentBlock = ({ fields, sitecoreContext }) => (
+const ContentBlock = ({ fields }) => (
   <React.Fragment>
-    <h2 className="display-5">WHAT is the airspeed velocity of an unladen swallow?</h2>
-    <h2 className="display-5">African or European?</h2>
-    { sitecoreContext.pageEditing ? <marquee>I am an element that will only display in Experience Editor</marquee> : null }
+    <Text tag="h2" className="display-4" field={fields.heading} />
 
-
-    <div style={{marginTop: 50}}>
-      <RichText className="contentDescription" field={fields.content} />
-    </div>
+    <RichText className="contentDescription" field={fields.content} />
   </React.Fragment>
 );
 
-export default withSitecoreContext()(ContentBlock);
+export default ContentBlock;

samples/react/src/index.js

@@ -2,7 +2,6 @@ import React from 'react';
 import ReactDOM from 'react-dom';
 import { BrowserRouter } from 'react-router-dom';
 import AppRoot from './AppRoot';
-import { setServerSideRenderingState } from './RouteHandler';
 import GraphQLClientFactory from './lib/GraphQLClientFactory';
 import config from './temp/config';
 import i18ninit from './i18n';
@@ -30,9 +29,6 @@ if (ssrRawJson) {
   __JSS_STATE__ = JSON.parse(ssrRawJson.innerHTML);
 }
 if (__JSS_STATE__) {
-  // push the initial SSR state into the route handler, where it will be used
-  setServerSideRenderingState(__JSS_STATE__);
-
   // when React initializes from a SSR-based initial state, you need to render with `hydrate` instead of `render`
   renderFunction = ReactDOM.hydrate;
 }
@@ -63,6 +59,7 @@ i18ninit().then(() => {
       path={window.location.pathname}
       Router={BrowserRouter}
       graphQLClient={graphQLClient}
+      ssrState={__JSS_STATE__}
     />,
     rootElement
   );