From 19e930994e263000512842a7c15782f2a0ae7700 Mon Sep 17 00:00:00 2001
From: Guillaume Chau <guillaume.b.chau@gmail.com>
Date: Sat, 8 Oct 2022 22:32:47 +0200
Subject: [PATCH] perf: improve startup time

---
 packages/histoire/src/node/collect/index.ts |  4 ++--
 packages/histoire/src/node/commands/dev.ts  |  4 ++--
 packages/histoire/src/node/server.ts        | 26 ++++++++++++++-------
 packages/histoire/src/node/vite.ts          |  6 ++++-
 4 files changed, 27 insertions(+), 13 deletions(-)

diff --git a/packages/histoire/src/node/collect/index.ts b/packages/histoire/src/node/collect/index.ts
index 01faf774..cf8e2e57 100644
--- a/packages/histoire/src/node/collect/index.ts
+++ b/packages/histoire/src/node/collect/index.ts
@@ -37,7 +37,7 @@ export function useCollectStories (options: UseCollectStoriesOptions, ctx: Conte
   })
 
   const threadsCount = ctx.mode === 'dev'
-    ? Math.max(Math.min(cpus().length / 2, 4), 1)
+    ? Math.max(cpus().length / 2, 1)
     : Math.max(cpus().length - 1, 1)
   console.log(pc.blue(`Using ${threadsCount} threads for story collection`))
 
@@ -45,8 +45,8 @@ export function useCollectStories (options: UseCollectStoriesOptions, ctx: Conte
     filename: new URL('./worker.js', import.meta.url).href,
     // WebContainer compatibility (Stackblitz)
     useAtomics: typeof process.versions.webcontainer !== 'string',
-    maxThreads: threadsCount,
     minThreads: threadsCount,
+    maxThreads: threadsCount,
   })
 
   function clearCache () {
diff --git a/packages/histoire/src/node/commands/dev.ts b/packages/histoire/src/node/commands/dev.ts
index 4b4044ea..ad2631e5 100644
--- a/packages/histoire/src/node/commands/dev.ts
+++ b/packages/histoire/src/node/commands/dev.ts
@@ -1,8 +1,8 @@
+import chokidar from 'chokidar'
+import pc from 'picocolors'
 import { resolveConfigFile } from '../config.js'
 import { createContext } from '../context.js'
 import { createServer } from '../server.js'
-import chokidar from 'chokidar'
-import pc from 'picocolors'
 
 export interface DevOptions {
   port: number
diff --git a/packages/histoire/src/node/server.ts b/packages/histoire/src/node/server.ts
index 755ca1fe..1820f07a 100644
--- a/packages/histoire/src/node/server.ts
+++ b/packages/histoire/src/node/server.ts
@@ -16,20 +16,28 @@ export interface CreateServerOptions {
 }
 
 export async function createServer (ctx: Context, options: CreateServerOptions = {}) {
-  const server = await createViteServer(await getViteConfigWithPlugins(false, ctx))
-  await server.pluginContainer.buildStart({})
+  const getViteServer = async (collecting: boolean) => {
+    const server = await createViteServer(await getViteConfigWithPlugins(collecting, ctx))
+    await server.pluginContainer.buildStart({})
+    return server
+  }
 
-  const nodeServer = await createViteServer(await getViteConfigWithPlugins(true, ctx))
-  await nodeServer.pluginContainer.buildStart({})
+  const [
+    server,
+    nodeServer,
+    ,
+    { stop: stopMdFileWatcher },
+  ] = await Promise.all([
+    getViteServer(false),
+    getViteServer(true),
+    watchStories(ctx),
+    createMarkdownFilesWatcher(ctx),
+  ] as const)
 
   const moduleLoader = useModuleLoader({
     server: nodeServer,
   })
 
-  await watchStories(ctx)
-
-  const { stop: stopMdFileWatcher } = await createMarkdownFilesWatcher(ctx)
-
   const pluginOnCleanups: (() => void | Promise<void>)[] = []
   for (const plugin of ctx.config.plugins) {
     if (plugin.onDev) {
@@ -183,6 +191,8 @@ export async function createServer (ctx: Context, options: CreateServerOptions =
     await wrapLogError('stopMdFileWatcher', () => stopMdFileWatcher())
   }
 
+  collect()
+
   return {
     server,
     close,
diff --git a/packages/histoire/src/node/vite.ts b/packages/histoire/src/node/vite.ts
index 18b571ba..f3d2d84e 100644
--- a/packages/histoire/src/node/vite.ts
+++ b/packages/histoire/src/node/vite.ts
@@ -415,8 +415,12 @@ if (import.meta.hot) {
     },
 
     configureServer (server) {
+      let firstMount = true
       server.ws.on('histoire:mount', () => {
-        notifyStoryChange()
+        if (!firstMount) {
+          notifyStoryChange()
+        }
+        firstMount = false
       })
 
       server.middlewares.use(async (req, res, next) => {