feat(build): conditionally include client side prerender hydration

Author: adamdbradley

src/client/platform-main-legacy.ts

@@ -123,9 +123,11 @@ export function createPlatformMainLegacy(namespace: string, Context: d.CoreConte
     }
   };
 
-  // if the HTML was generated from SSR
-  // then let's walk the tree and generate vnodes out of the data
-  createVNodesFromSsr(plt, domApi, rootElm);
+  if (__BUILD_CONDITIONALS__.prerenderClientSide) {
+    // if the HTML was generated from prerendering
+    // then let's walk the tree and generate vnodes out of the data
+    createVNodesFromSsr(plt, domApi, rootElm);
+  }
 
 
   function defineComponent(cmpMeta: d.ComponentMeta, HostElementConstructor: any) {

src/client/platform-main.ts

@@ -116,8 +116,8 @@ export function createPlatformMain(namespace: string, Context: d.CoreContext, wi
     }
   };
 
-  if (__BUILD_CONDITIONALS__.browserModuleLoader) {
-    // if the HTML was generated from SSR
+  if (__BUILD_CONDITIONALS__.prerenderClientSide) {
+    // if the HTML was generated from prerendering
     // then let's walk the tree and generate vnodes out of the data
     createVNodesFromSsr(plt, domApi, rootElm);
   }

src/compiler/prerender/prerender-app.ts

@@ -29,6 +29,17 @@ export async function prerenderOutputTargets(config: d.Config, compilerCtx: d.Co
 }
 
 
+export function shouldPrerender(config: d.Config) {
+  if (!config.srcIndexHtml) {
+    return false;
+  }
+  const outputTargets = (config.outputTargets as d.OutputTargetWww[]).filter(o => {
+    return o.type === 'www' && o.indexHtml && o.hydrateComponents && o.prerenderLocations && o.prerenderLocations.length > 0;
+  });
+  return (outputTargets.length > 0);
+}
+
+
 async function prerenderOutputTarget(config: d.Config, compilerCtx: d.CompilerCtx, buildCtx: d.BuildCtx, outputTarget: d.OutputTargetWww, entryModules: d.EntryModule[]) {
   // if there was src index.html file, then the process before this one
   // would have already loaded and updated the src index to its www path

src/declarations/build-conditionals.ts

@@ -22,6 +22,7 @@ export interface BuildConditionals {
 
   // ssr
   ssrServerSide: boolean;
+  prerenderClientSide: boolean;
 
   // encapsulation
   styles: boolean;

src/util/build-conditionals.ts

@@ -1,6 +1,7 @@
 import * as d from '../declarations';
 import { ENCAPSULATION, MEMBER_TYPE, PROP_TYPE } from './constants';
 import { isTsFile } from '../compiler/util';
+import { shouldPrerender } from '../compiler/prerender/prerender-app';
 
 
 export function getDefaultBuildConditionals(): d.BuildConditionals {
@@ -11,6 +12,7 @@ export function getDefaultBuildConditionals(): d.BuildConditionals {
     shadowDom: true,
     slotPolyfill: true,
     ssrServerSide: true,
+    prerenderClientSide: true,
     devInspector: true,
     hotModuleReplacement: true,
     verboseError: true,
@@ -79,6 +81,7 @@ export async function setBuildConditionals(
     es5: false,
     cssVarShim: false,
     ssrServerSide: false,
+    prerenderClientSide: false,
     shadowDom: false,
     slotPolyfill: false,
     event: false,
@@ -118,6 +121,7 @@ export async function setBuildConditionals(
     if (coreBuild.slotPolyfill) {
       coreBuild.slotPolyfill = !!(buildCtx.hasSlot);
     }
+    coreBuild.prerenderClientSide = shouldPrerender(config);
     compilerCtx.lastBuildConditionalsBrowserEsm = coreBuild;
 
   } else if (coreId === 'core.pf') {
@@ -126,6 +130,7 @@ export async function setBuildConditionals(
     coreBuild.polyfills = true;
     coreBuild.cssVarShim = true;
     coreBuild.slotPolyfill = !!(buildCtx.hasSlot);
+    coreBuild.prerenderClientSide = shouldPrerender(config);
     compilerCtx.lastBuildConditionalsBrowserEs5 = coreBuild;
 
   } else if (coreId === 'esm.es5') {