perf(): use JSON.parse() when metadata is > 10KB

ionic-team · Jun 26, 2019 · ab0e9d6 · mathiasbynens · Jun 26, 2019 · ab0e9d6
1 parent 2054cc7
commit ab0e9d6
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Showing 2 changed files with 8 additions and 2 deletions.
diff --git a/src/compiler/app-core/format-component-runtime-meta.ts b/src/compiler/app-core/format-component-runtime-meta.ts
@@ -33,8 +33,13 @@ export function formatComponentRuntimeMeta(compilerMeta: d.ComponentCompilerMeta
 
 
 export function stringifyRuntimeData(data: any) {
-  // stringify the data, then remove property double-quotes so they can be property renamed
-  return JSON.stringify(data);
+  const json = JSON.stringify(data);
+  if (json.length > 10000) {
+    // JSON metadata is big, JSON.parse() is faster
+    // https://twitter.com/mathias/status/1143551692732030979
+    return `JSON.parse(${JSON.stringify(json)})`;
+  }
+  return json;
 }
 
 

diff --git a/src/compiler/component-lazy/generate-lazy-module.ts b/src/compiler/component-lazy/generate-lazy-module.ts
@@ -24,6 +24,7 @@ export async function generateLazyModules(config: d.Config, compilerCtx: d.Compi
   ]);
 
   const lazyRuntimeData = formatLazyBundlesRuntimeMeta(bundleModules);
+  config.logger.debug(`Upfront metadata is ${lazyRuntimeData.length} bytes`);
   const entryResults = rollupResults.filter(rollupResult => !rollupResult.isComponent && rollupResult.isEntry);
   await Promise.all(
     entryResults.map(rollupResult => {