From 754c2a190baac2a1ccce47fa37e863865e0072fd Mon Sep 17 00:00:00 2001
From: Jason Cox <contact@jasonbcox.com>
Date: Wed, 23 Sep 2020 08:30:06 -0700
Subject: [PATCH] Generate v1 -> v2 redirects for all production pages (#611)

---
 v2/gatsby-node.js | 33 +++++++++++++++++----------------
 1 file changed, 17 insertions(+), 16 deletions(-)

diff --git a/v2/gatsby-node.js b/v2/gatsby-node.js
index 0ae88690d..2ac995f17 100644
--- a/v2/gatsby-node.js
+++ b/v2/gatsby-node.js
@@ -39,11 +39,11 @@ const createRedirectForEachLocale = async (createRedirect, page) => {
   await forEachLocale(
     page,
     async (page, context, localizationParams, localizedPath) => {
+      // By default, assume v1 paths of the form `/path.html` transform to
+      // v2 paths of the form `/path/`.
       createRedirect({
-        fromPath: localizedPath,
-        // By default, assume paths of the form `/path/` transform to
-        // v1 paths of the form `/path.html`
-        toPath: localizedPath.replace(/\/$/, "") + ".html",
+        fromPath: localizedPath.replace(/\/$/, "") + ".html",
+        toPath: localizedPath,
         redirectInBrowser: true,
         isPermanent: false,
       })
@@ -92,7 +92,13 @@ exports.createPages = async ({ graphql, actions, reporter }) => {
       // In production, we redirect in-development v2 pages to v1 equivalent routes.
       // In non-prod environments, we create all pages and do not redirect.
       if (process.env.GATSBY_APP_ENV == "prod") {
-        await createRedirectForEachLocale(createRedirect, page)
+        await createRedirectForEachLocale((redirectArgs) => {
+          createRedirect({
+            ...redirectArgs,
+            fromPath: redirectArgs.toPath,
+            toPath: redirectArgs.fromPath,
+          })
+        }, page)
       } else {
         await createPageForEachLocale(createPage, page)
       }
@@ -102,20 +108,15 @@ exports.createPages = async ({ graphql, actions, reporter }) => {
 
 exports.onCreatePage = async ({
   page,
-  actions: { createPage, deletePage },
+  actions: { createPage, createRedirect, deletePage },
 }) => {
   // Delete the original page (since we are gonna create localized versions of it)
   await deletePage(page)
 
   // Create one page for each locale
-  await forEachLocale(
-    page,
-    (page, context, localizationParams, localizedPath) => {
-      createPage({
-        ...page,
-        path: localizedPath,
-        context,
-      })
-    }
-  )
+  await createPageForEachLocale(createPage, page)
+
+  // Although not all pages have v1 equivalents, it doesn't hurt to generate
+  // redirects for all of them to point at v2 pages.
+  await createRedirectForEachLocale(createRedirect, page)
 }