From 7ef839a755b966fd49b5cdcd53a830f69a807a21 Mon Sep 17 00:00:00 2001
From: MrOrz <johnsonliang7@gmail.com>
Date: Sat, 4 Dec 2021 17:18:22 +0800
Subject: [PATCH] Handle SSG case (ctx.req being undefined)

---
 pages/_document.js | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/pages/_document.js b/pages/_document.js
index 0c241e77..a8e9490d 100644
--- a/pages/_document.js
+++ b/pages/_document.js
@@ -122,14 +122,16 @@ MyDocument.getInitialProps = async ctx => {
     const sheets = new ServerStyleSheets();
     const originalRenderPage = ctx.renderPage;
 
+    // ctx.req will be undefined on static page build
+    const serverSideCookie = ctx.req?.headers?.cookie
+      ? cookie.parse(ctx.req.headers.cookie)
+      : {};
+
     ctx.renderPage = () =>
       originalRenderPage({
         enhanceApp: App => props =>
           sheets.collect(
-            <App
-              {...props}
-              serverSideCookie={cookie.parse(ctx.req.headers.cookie)}
-            />
+            <App {...props} serverSideCookie={serverSideCookie} />
           ),
       });