Sync Next.js redirects to Cloudflare

Author: cometkim

next.config.mjs

@@ -1,5 +1,8 @@
-// @ts-check
-import fs from "fs";
+// @ ts-check
+
+import * as assert from "node:assert/strict";
+import * as path from "node:path";
+import * as fs from "node:fs/promises";
 import webpack from "webpack";
 import rehypeSlug from "rehype-slug";
 import remarkGfm from "remark-gfm";
@@ -8,14 +11,15 @@ import remarkFrontmatter from "remark-frontmatter";
 import remarkMdxFrontmatter from "remark-mdx-frontmatter";
 import { createLoader } from "simple-functional-loader";
 
-const bsconfig = JSON.parse(fs.readFileSync("./rescript.json").toString());
+const bsconfig = JSON.parse((await fs.readFile("./rescript.json", "utf8")).toString());
 
 const { ProvidePlugin } = webpack;
 
 const transpileModules = ["rescript"].concat(bsconfig["bs-dependencies"]);
 
+/** @type {import("next").NextConfig} */
 const config = {
-  output: "export",
+  output: process.env.NODE_ENV === "production" ? "export" : undefined,
   pageExtensions: ["jsx", "js", "bs.js", "mdx", "mjs"],
   env: {
     ENV: process.env.NODE_ENV,
@@ -85,7 +89,7 @@ const config = {
     return config;
   },
   async redirects() {
-    return [
+    const redirects = [
       {
         source: "/community",
         destination: "/community/overview",
@@ -126,6 +130,8 @@ const config = {
         destination: "/docs/manual/latest/typescript-integration",
         permanent: true,
       },
+    ];
+    const splatRedirects = [
       {
         source: "/docs/manual/latest/:slug*",
         destination: `/docs/manual/${process.env.VERSION_LATEST}/:slug*`,
@@ -147,6 +153,33 @@ const config = {
         permanent: false,
       },
     ];
+
+    /**
+     * @typedef {{
+     *   source: string,
+     *   destination: string,
+     *   permanent: boolean,
+     * }} Redirect
+     */
+
+    const redirectsFile = path.join(import.meta.dirname, "public/_redirects");
+    await fs.writeFile(
+      redirectsFile,
+      redirects
+        .map(({ source, destination, permanent }) => {
+          return `${source}  ${destination}  ${permanent ? 308 : 307}`;
+        }).join("\n") +
+      "\n" +
+      splatRedirects.map(({ source, destination, permanent }) => {
+        const splatPattern = /:(\w+)\*$/;
+        assert.match(source, splatPattern);
+        assert.match(destination, splatPattern);
+        return `${source.replace(splatPattern, "*")}  ${destination.replace(splatPattern, ":splat")}  ${permanent ? 308 : 307}`;
+      }).join("\n"),
+      "utf8",
+    );
+
+    return [...redirects, ...splatRedirects];
   },
 };
 

public/_redirects

@@ -1,16 +1,12 @@
 /community  /community/overview  308
-
 /bucklescript-rebranding  /blog/bucklescript-is-rebranding  308
-
 /docs/manual/latest/migrate-from-bucklescript-reason  /docs/manual/v10.0.0/migrate-from-bucklescript-reason  308
-/docs/manual/latest/unboxed                           /docs/manual/v10.0.0/unboxed                           308
-/docs/gentype/latest/introduction                     /docs/manual/latest/typescript-integration             308
-/docs/gentype/latest/getting-started                  /docs/manual/latest/typescript-integration             308
-/docs/gentype/latest/usage                            /docs/manual/latest/typescript-integration             308
-/docs/gentype/latest/supported-types                  /docs/manual/latest/typescript-integration             308
-
+/docs/manual/latest/unboxed  /docs/manual/v10.0.0/unboxed  308
+/docs/gentype/latest/introduction  /docs/manual/latest/typescript-integration  308
+/docs/gentype/latest/getting-started  /docs/manual/latest/typescript-integration  308
+/docs/gentype/latest/usage  /docs/manual/latest/typescript-integration  308
+/docs/gentype/latest/supported-types  /docs/manual/latest/typescript-integration  308
 /docs/manual/latest/*  /docs/manual/v11.0.0/:splat  307
+/docs/manual/next/*  /docs/manual/v12.0.0/:splat  307
 /llms/manual/latest/*  /llms/manual/v11.0.0/:splat  307
-
-/docs/manual/next/*    /docs/manual/v12.0.0/:splat  307
-/llms/manual/next/*    /llms/manual/v12.0.0/:splat  307
+/llms/manual/next/*  /llms/manual/v12.0.0/:splat  307

scripts/sync-redirects.mjs

@@ -0,0 +1,25 @@
+import * as path from "node:path";
+import * as fs from "node:fs";
+
+import nextConfig from "../next.config.mjs";
+
+const redirectsConfig = await nextConfig.redirects();
+
+/**
+ * @param {{
+ *   source: string,
+ *   destination: string,
+ *   permanent: boolean,
+ * }} config 
+ * @return {string}
+ */
+function lineFormat({
+  source,
+  destination,
+  permanent,
+}) {
+  return `${source}  ${destination}  ${permanent ? 308 : 307}`;
+}
+
+const redirects = redirectsConfig.map(lineFormat).join("\n");
+const redirectsFile = path.join(import.meta.dirname, "../public/_redirects");