Refactoring (#554)

- rename BuildOptions#tempDir to BuildOptions#buildDir
- simplify the default OpenNext config
- rename a few arguments for consistency / clarity
- compile the configuration into the OS temp dir
- pin the Next version used in CI to npm latest

Author: vicb

.github/workflows/e2e.yml

@@ -33,7 +33,7 @@ jobs:
       - name: Get Latest Next Version
         id: get_latest_version
         run: |
-          latest_version=$(curl -s https://api.github.com/repos/vercel/next.js/releases/latest | jq -r '.tag_name')
+          latest_version=$(curl -s https://registry.npmjs.org/-/package/next/dist-tags | jq -r '.latest')
           echo "Latest version: $latest_version"
           echo "LATEST_VERSION=$latest_version" >> $GITHUB_ENV
           echo "LATEST_VERSION=$latest_version" >> $GITHUB_OUTPUT

packages/open-next/src/build.ts

@@ -1,5 +1,5 @@
 import cp from "node:child_process";
-import fs, { readFileSync } from "node:fs";
+import fs from "node:fs";
 import { createRequire as topLevelCreateRequire } from "node:module";
 import os from "node:os";
 import path from "node:path";
@@ -47,9 +47,9 @@ export async function build(
   showWindowsWarning();
 
   // Load open-next.config.ts
-  const tempDir = initTempDir();
+  const tempBuildDir = fs.mkdtempSync(path.join(os.tmpdir(), "open-next-tmp"));
   let configPath = compileOpenNextConfigNode(
-    tempDir,
+    tempBuildDir,
     openNextConfigPath,
     nodeExternals,
   );
@@ -64,10 +64,10 @@ export async function build(
   }
   validateConfig(config);
 
-  compileOpenNextConfigEdge(tempDir, config, openNextConfigPath);
+  compileOpenNextConfigEdge(tempBuildDir, config, openNextConfigPath);
 
   // Initialize options
-  const options = normalizeOptions(config);
+  const options = normalizeOptions(config, tempBuildDir);
   logger.setLevel(options.debug ? "debug" : "info");
 
   // Pre-build validation
@@ -82,7 +82,7 @@ export async function build(
 
   // Generate deployable bundle
   printHeader("Generating bundle");
-  initOutputDir(tempDir, options);
+  initOutputDir(options);
 
   // Compile cache.ts
   compileCache(options);
@@ -113,14 +113,6 @@ function showWindowsWarning() {
   );
 }
 
-function initTempDir() {
-  const dir = path.join(process.cwd(), ".open-next");
-  const tempDir = path.join(dir, ".build");
-  fs.rmSync(dir, { recursive: true, force: true });
-  fs.mkdirSync(tempDir, { recursive: true });
-  return tempDir;
-}
-
 function checkRunningInsideNextjsApp(options: BuildOptions) {
   const { appPath } = options;
   const extension = ["js", "cjs", "mjs", "ts"].find((ext) =>
@@ -175,34 +167,14 @@ function printOpenNextVersion(options: BuildOptions) {
   logger.info(`OpenNext v${options.openNextVersion}`);
 }
 
-function initOutputDir(srcTempDir: string, options: BuildOptions) {
+function initOutputDir(options: BuildOptions) {
   // We need to get the build relative to the cwd to find the compiled config
   // This is needed for the case where the app is a single-version monorepo and the package.json is in the root of the monorepo
   // where the build is in the app directory, but the compiled config is in the root of the monorepo.
-  const openNextConfig = readFileSync(
-    path.join(srcTempDir, "open-next.config.mjs"),
-    "utf8",
-  );
-  let openNextConfigEdge: string | null = null;
-  if (fs.existsSync(path.join(srcTempDir, "open-next.config.edge.mjs"))) {
-    openNextConfigEdge = readFileSync(
-      path.join(srcTempDir, "open-next.config.edge.mjs"),
-      "utf8",
-    );
-  }
   fs.rmSync(options.outputDir, { recursive: true, force: true });
-  const destTempDir = options.tempDir;
-  fs.mkdirSync(destTempDir, { recursive: true });
-  fs.writeFileSync(
-    path.join(destTempDir, "open-next.config.mjs"),
-    openNextConfig,
-  );
-  if (openNextConfigEdge) {
-    fs.writeFileSync(
-      path.join(destTempDir, "open-next.config.edge.mjs"),
-      openNextConfigEdge,
-    );
-  }
+  const { buildDir } = options;
+  fs.mkdirSync(buildDir, { recursive: true });
+  fs.cpSync(options.tempBuildDir, buildDir, { recursive: true });
 }
 
 async function createWarmerBundle(options: BuildOptions) {
@@ -215,7 +187,7 @@ async function createWarmerBundle(options: BuildOptions) {
   fs.mkdirSync(outputPath, { recursive: true });
 
   // Copy open-next.config.mjs into the bundle
-  copyOpenNextConfig(options.tempDir, outputPath);
+  copyOpenNextConfig(options.buildDir, outputPath);
 
   // Build Lambda code
   // note: bundle in OpenNext package b/c the adatper relys on the
@@ -258,7 +230,7 @@ async function createRevalidationBundle(options: BuildOptions) {
   fs.mkdirSync(outputPath, { recursive: true });
 
   //Copy open-next.config.mjs into the bundle
-  copyOpenNextConfig(options.tempDir, outputPath);
+  copyOpenNextConfig(options.buildDir, outputPath);
 
   // Build Lambda code
   await esbuildAsync(
@@ -297,7 +269,7 @@ async function createImageOptimizationBundle(options: BuildOptions) {
   fs.mkdirSync(outputPath, { recursive: true });
 
   // Copy open-next.config.mjs into the bundle
-  copyOpenNextConfig(options.tempDir, outputPath);
+  copyOpenNextConfig(options.buildDir, outputPath);
 
   const plugins = [
     openNextResolvePlugin({
@@ -640,7 +612,7 @@ async function createCacheAssets(options: BuildOptions) {
       );
 
       //Copy open-next.config.mjs into the bundle
-      copyOpenNextConfig(options.tempDir, providerPath);
+      copyOpenNextConfig(options.buildDir, providerPath);
 
       // TODO: check if metafiles doesn't contain duplicates
       fs.writeFileSync(
@@ -664,7 +636,7 @@ export function compileCache(
 ) {
   const { config } = options;
   const ext = format === "cjs" ? "cjs" : "mjs";
-  const outfile = path.join(options.outputDir, ".build", `cache.${ext}`);
+  const outfile = path.join(options.buildDir, `cache.${ext}`);
 
   const isAfter15 = compareSemver(options.nextVersion, "15.0.0") >= 0;
 
@@ -699,7 +671,7 @@ async function createMiddleware(options: BuildOptions) {
 
   // Get middleware manifest
   const middlewareManifest = JSON.parse(
-    readFileSync(
+    fs.readFileSync(
       path.join(appBuildOutputPath, ".next/server/middleware-manifest.json"),
       "utf8",
     ),
@@ -725,7 +697,7 @@ async function createMiddleware(options: BuildOptions) {
 
     // Copy open-next.config.mjs
     copyOpenNextConfig(
-      options.tempDir,
+      options.buildDir,
       outputPath,
       config.middleware.override?.wrapper === "cloudflare",
     );
@@ -743,7 +715,7 @@ async function createMiddleware(options: BuildOptions) {
   } else {
     await buildEdgeBundle({
       entrypoint: path.join(__dirname, "core", "edgeFunctionHandler.js"),
-      outfile: path.join(outputDir, ".build", "middleware.mjs"),
+      outfile: path.join(options.buildDir, "middleware.mjs"),
       ...commonMiddlewareOptions,
       onlyBuildOnce: true,
     });

packages/open-next/src/build/compileConfig.ts

@@ -7,28 +7,21 @@ import { OpenNextConfig } from "types/open-next.js";
 import logger from "../logger.js";
 
 export function compileOpenNextConfigNode(
-  tempDir: string,
+  outputDir: string,
   openNextConfigPath?: string,
   nodeExternals?: string,
 ) {
   const sourcePath = path.join(
     process.cwd(),
     openNextConfigPath ?? "open-next.config.ts",
   );
-  const outputPath = path.join(tempDir, "open-next.config.mjs");
+  const outputPath = path.join(outputDir, "open-next.config.mjs");
 
   //Check if open-next.config.ts exists
   if (!fs.existsSync(sourcePath)) {
     //Create a simple open-next.config.mjs file
     logger.debug("Cannot find open-next.config.ts. Using default config.");
-    fs.writeFileSync(
-      outputPath,
-      [
-        "var config = { default: { } };",
-        "var open_next_config_default = config;",
-        "export { open_next_config_default as default };",
-      ].join("\n"),
-    );
+    fs.writeFileSync(outputPath, "export default { default: { } };");
   } else {
     buildSync({
       entryPoints: [sourcePath],

packages/open-next/src/build/createServerBundle.ts

@@ -144,7 +144,7 @@ async function generateBundle(
 
   const ext = fnOptions.runtime === "deno" ? "mjs" : "cjs";
   fs.copyFileSync(
-    path.join(outputDir, ".build", `cache.${ext}`),
+    path.join(options.buildDir, `cache.${ext}`),
     path.join(outputPath, packagePath, "cache.cjs"),
   );
 
@@ -158,24 +158,21 @@ async function generateBundle(
     await bundleNextServer(path.join(outputPath, packagePath), appPath);
   }
 
-  // // Copy middleware
+  // Copy middleware
   if (
     !config.middleware?.external &&
-    existsSync(path.join(outputDir, ".build", "middleware.mjs"))
+    existsSync(path.join(options.buildDir, "middleware.mjs"))
   ) {
     fs.copyFileSync(
-      path.join(outputDir, ".build", "middleware.mjs"),
+      path.join(options.buildDir, "middleware.mjs"),
       path.join(outputPath, packagePath, "middleware.mjs"),
     );
   }
 
   // Copy open-next.config.mjs
-  copyOpenNextConfig(
-    path.join(outputDir, ".build"),
-    path.join(outputPath, packagePath),
-  );
+  copyOpenNextConfig(options.buildDir, path.join(outputPath, packagePath));
 
-  //Copy env files
+  // Copy env files
   copyEnvFile(appBuildOutputPath, packagePath, outputPath);
 
   // Copy all necessary traced files

packages/open-next/src/build/edge/createEdgeBundle.ts

@@ -179,7 +179,7 @@ export async function generateEdgeBundle(
   fs.mkdirSync(outputPath, { recursive: true });
 
   // Copy open-next.config.mjs
-  copyOpenNextConfig(path.join(outputDir, ".build"), outputPath, true);
+  copyOpenNextConfig(options.buildDir, outputPath, true);
 
   // Load middleware manifest
   const middlewareManifest = JSON.parse(

packages/open-next/src/build/helper.ts

@@ -17,7 +17,7 @@ const __dirname = url.fileURLToPath(new URL(".", import.meta.url));
 
 export type BuildOptions = ReturnType<typeof normalizeOptions>;
 
-export function normalizeOptions(config: OpenNextConfig) {
+export function normalizeOptions(config: OpenNextConfig, tempBuildDir: string) {
   const appPath = path.join(process.cwd(), config.appPath || ".");
   const buildOutputPath = path.join(
     process.cwd(),
@@ -44,14 +44,15 @@ export function normalizeOptions(config: OpenNextConfig) {
     appPackageJsonPath,
     appPath,
     appPublicPath: path.join(appPath, "public"),
+    buildDir: path.join(outputDir, ".build"),
     config,
     debug: Boolean(process.env.OPEN_NEXT_DEBUG) ?? false,
     monorepoRoot,
     nextVersion: getNextVersion(appPath),
     openNextVersion: getOpenNextVersion(),
     outputDir,
     packager,
-    tempDir: path.join(outputDir, ".build"),
+    tempBuildDir,
   };
 }
 
@@ -77,6 +78,7 @@ function findMonorepoRoot(appPath: string) {
   // note: a lock file (package-lock.json, yarn.lock, or pnpm-lock.yaml) is
   //       not found in the app's directory or any of its parent directories.
   //       We are going to assume that the app is not part of a monorepo.
+  logger.warn("No lockfile found");
   return { root: appPath, packager: "npm" as const };
 }
 
@@ -273,17 +275,17 @@ export function compareSemver(v1: string, v2: string): number {
 }
 
 export function copyOpenNextConfig(
-  tempDir: string,
-  outputPath: string,
+  inputDir: string,
+  outputDir: string,
   isEdge = false,
 ) {
   // Copy open-next.config.mjs
   fs.copyFileSync(
     path.join(
-      tempDir,
+      inputDir,
       isEdge ? "open-next.config.edge.mjs" : "open-next.config.mjs",
     ),
-    path.join(outputPath, "open-next.config.mjs"),
+    path.join(outputDir, "open-next.config.mjs"),
   );
 }