Force redirect for notion redirects

Author: jhchabran

Diff for: src/scripts/generate-redirects.mjs

@@ -7,7 +7,9 @@ import fs from 'fs/promises'
 
 import redirects from './redirects.mjs'
 
-const redirectLines = (await redirects()).map(({ source, destination }) => `${source} ${destination}`).join('\n')
+const foo = await redirects()
+
+const redirectLines = (await redirects()).map((entry) => `${entry.source} ${entry.destination}${entry.force ? ' 302!' : ''}`).join('\n')
 const lines = `\n# Generated by generate-redirects.mjs from Git history\n${redirectLines}\n`
 
 console.log('Redirects:\n', lines)

Diff for: src/scripts/redirects.mjs

@@ -31,10 +31,21 @@ export function cleanupRedirects(movedPages) {
 /**
  * Reads Notion specific redirections from data/notion_migration.yaml.
  *
- * @returns {redirections: {source: string, destination: string}[]}
+ * @returns {redirections: {source: string, destination: string, force: true}[]}
  */
 async function readNotionMigrationRedirects() {
-    return load(await readFile('data/notion_migration.yaml', 'utf8'))
+    const data = load(await readFile('data/notion_migration.yaml', 'utf8'))
+
+    // While NextJS is okay if content exists when setting up a redirection,
+    // Netlify doesn't: it will skip the redirection entirely if it finds
+    // existing content.
+    // To go around that, we add a new field 'force' that the script that
+    // generate the final _redirects file used by Netlify uses to append
+    // 301! on that entry, effectively forcing the redirection.
+    for ( let entry of data.redirections ) {
+        entry["force"] = true
+    }
+    return data
 }
 
 /**
@@ -46,12 +57,11 @@ export default async function redirects() {
     const movedPages = await getMovedPagesFromHistory()
     const notionRedirections = await readNotionMigrationRedirects()
     return cleanupRedirects([
-        ...notionRedirections.redirections,
         ...movedPages,
         // Add custom redirects
         {
             source: '/careers',
             destination: 'https://about.sourcegraph.com/jobs',
         },
-    ])
+    ]).concat(notionRedirections.redirections) // we skip the cleanup because notion redirects are always going outside.
 }