feat(cloudflare): generated wrangler configuration

playground/wrangler.toml

@@ -2,12 +2,10 @@ name = "nitro-test"
 
 compatibility_date = "2024-09-19"
 
-assets = { directory = "./.output/public/", binding = "ASSETS" }
+# [[durable_objects.bindings]]
+# name = "$DurableObject"
+# class_name = "$DurableObject"
 
-[[durable_objects.bindings]]
-name = "$DurableObject"
-class_name = "$DurableObject"
-
-[[migrations]]
-tag = "v1"
-new_sqlite_classes = ["$DurableObject"]
+# [[migrations]]
+# tag = "v1"
+# new_sqlite_classes = ["$DurableObject"]

src/presets/cloudflare/preset.ts

@@ -2,7 +2,12 @@ import { defineNitroPreset } from "nitropack/kit";
 import { writeFile } from "nitropack/kit";
 import type { Nitro } from "nitropack/types";
 import { resolve } from "pathe";
-import { writeCFPagesFiles, writeCFPagesStaticFiles } from "./utils";
+import {
+  writeWranglerConfig,
+  writeCFRoutes,
+  writeCFPagesHeaders,
+  writeCFPagesRedirects,
+} from "./utils";
 
 export type { CloudflareOptions as PresetOptions } from "./types";
 
@@ -52,7 +57,10 @@ const cloudflarePages = defineNitroPreset(
     },
     hooks: {
       async compiled(nitro: Nitro) {
-        await writeCFPagesFiles(nitro);
+        await writeWranglerConfig(nitro, true /* pages */);
+        await writeCFRoutes(nitro);
+        await writeCFPagesHeaders(nitro);
+        await writeCFPagesRedirects(nitro);
       },
     },
   },
@@ -76,7 +84,9 @@ const cloudflarePagesStatic = defineNitroPreset(
     },
     hooks: {
       async compiled(nitro: Nitro) {
-        await writeCFPagesStaticFiles(nitro);
+        await writeWranglerConfig(nitro, true /* pages */);
+        await writeCFPagesHeaders(nitro);
+        await writeCFPagesRedirects(nitro);
       },
     },
   },
@@ -173,8 +183,8 @@ const cloudflareModule = defineNitroPreset(
     entry: "./runtime/cloudflare-module",
     exportConditions: ["workerd"],
     commands: {
-      preview: "npx wrangler dev ./server/index.mjs --assets ./public/",
-      deploy: "npx wrangler deploy",
+      preview: "npx wrangler dev -c ./server/wrangler.json",
+      deploy: "npx wrangler deploy -c ./server/wrangler.json",
     },
     unenv: {
       external: [...cloudflareExternals],
@@ -192,6 +202,7 @@ const cloudflareModule = defineNitroPreset(
     },
     hooks: {
       async compiled(nitro: Nitro) {
+        await writeWranglerConfig(nitro, false /* module */);
         await writeFile(
           resolve(nitro.options.output.dir, "package.json"),
           JSON.stringify({ private: true, main: "./server/index.mjs" }, null, 2)

src/presets/cloudflare/types.ts

@@ -28,6 +28,11 @@ export interface CloudflareOptions {
    */
   wrangler?: WranglerConfig;
 
+  /**
+   * Disable the automatic generation of .wrangler/deploy/config.json
+   */
+  noWranglerDeployConfig?: boolean;
+
   pages: {
     /**
      * Nitro will automatically generate a `_routes.json` that controls which files get served statically and

src/presets/cloudflare/types.wrangler.ts

@@ -24,7 +24,9 @@
  * - `@breaking`: the deprecation/optionality is a breaking change from Wrangler v1.
  * - `@todo`: there's more work to be done (with details attached).
  */
-export type Config = ConfigFields<DevConfig> & PagesConfigFields & Environment;
+export type Config = Partial<
+  ConfigFields<DevConfig> & PagesConfigFields & Environment
+>;
 
 export type RawConfig = Partial<ConfigFields<RawDevConfig>> &
   PagesConfigFields &

src/presets/cloudflare/utils.ts

@@ -1,10 +1,12 @@
-import { existsSync, promises as fsp } from "node:fs";
-import { parseTOML, stringifyTOML } from "confbox";
-import defu from "defu";
+import { existsSync } from "node:fs";
+import { readFile } from "node:fs/promises";
+import { relative, dirname } from "node:path";
+import { writeFile } from "nitropack/kit";
+import { parseTOML } from "confbox";
+import { defu } from "defu";
 import { globby } from "globby";
 import type { Nitro } from "nitropack/types";
 import { join, resolve } from "pathe";
-import { isCI } from "std-env";
 import {
   joinURL,
   hasProtocol,
@@ -13,20 +15,9 @@ import {
   withoutLeadingSlash,
 } from "ufo";
 import type { CloudflarePagesRoutes } from "./types";
+import type { Config as WranglerConfig } from "./types.wrangler";
 
-export async function writeCFPagesFiles(nitro: Nitro) {
-  await writeCFRoutes(nitro);
-  await writeCFPagesHeaders(nitro);
-  await writeCFPagesRedirects(nitro);
-  await writeCFWrangler(nitro);
-}
-
-export async function writeCFPagesStaticFiles(nitro: Nitro) {
-  await writeCFPagesHeaders(nitro);
-  await writeCFPagesRedirects(nitro);
-}
-
-async function writeCFRoutes(nitro: Nitro) {
+export async function writeCFRoutes(nitro: Nitro) {
   const _cfPagesConfig = nitro.options.cloudflare?.pages || {};
   const routes: CloudflarePagesRoutes = {
     version: _cfPagesConfig.routes?.version || 1,
@@ -35,9 +26,10 @@ async function writeCFRoutes(nitro: Nitro) {
   };
 
   const writeRoutes = () =>
-    fsp.writeFile(
+    writeFile(
       resolve(nitro.options.output.dir, "_routes.json"),
-      JSON.stringify(routes, undefined, 2)
+      JSON.stringify(routes, undefined, 2),
+      true
     );
 
   if (_cfPagesConfig.defaultRoutes === false) {
@@ -107,7 +99,7 @@ function comparePaths(a: string, b: string) {
   return a.split("/").length - b.split("/").length || a.localeCompare(b);
 }
 
-async function writeCFPagesHeaders(nitro: Nitro) {
+export async function writeCFPagesHeaders(nitro: Nitro) {
   const headersPath = join(nitro.options.output.dir, "_headers");
   const contents = [];
 
@@ -129,7 +121,7 @@ async function writeCFPagesHeaders(nitro: Nitro) {
   }
 
   if (existsSync(headersPath)) {
-    const currentHeaders = await fsp.readFile(headersPath, "utf8");
+    const currentHeaders = await readFile(headersPath, "utf8");
     if (/^\/\* /m.test(currentHeaders)) {
       nitro.logger.info(
         "Not adding Nitro fallback to `_headers` (as an existing fallback was found)."
@@ -142,10 +134,10 @@ async function writeCFPagesHeaders(nitro: Nitro) {
     contents.unshift(currentHeaders);
   }
 
-  await fsp.writeFile(headersPath, contents.join("\n"));
+  await writeFile(headersPath, contents.join("\n"), true);
 }
 
-async function writeCFPagesRedirects(nitro: Nitro) {
+export async function writeCFPagesRedirects(nitro: Nitro) {
   const redirectsPath = join(nitro.options.output.dir, "_redirects");
   const staticFallback = existsSync(
     join(nitro.options.output.publicDir, "404.html")
@@ -169,7 +161,7 @@ async function writeCFPagesRedirects(nitro: Nitro) {
   }
 
   if (existsSync(redirectsPath)) {
-    const currentRedirects = await fsp.readFile(redirectsPath, "utf8");
+    const currentRedirects = await readFile(redirectsPath, "utf8");
     if (/^\/\* /m.test(currentRedirects)) {
       nitro.logger.info(
         "Not adding Nitro fallback to `_redirects` (as an existing fallback was found)."
@@ -182,37 +174,116 @@ async function writeCFPagesRedirects(nitro: Nitro) {
     contents.unshift(currentRedirects);
   }
 
-  await fsp.writeFile(redirectsPath, contents.join("\n"));
+  await writeFile(redirectsPath, contents.join("\n"), true);
 }
 
-async function writeCFWrangler(nitro: Nitro) {
-  type WranglerConfig = typeof nitro.options.cloudflare.wrangler;
+// https://developers.cloudflare.com/workers/wrangler/configuration/#generated-wrangler-configuration
+export async function writeWranglerConfig(nitro: Nitro, isPages: boolean) {
+  // Compute path to generated wrangler.json
+  const wranglerConfigDir = nitro.options.output.serverDir;
+  const wranglerConfigPath = join(wranglerConfigDir, "wrangler.json");
 
-  const inlineConfig: WranglerConfig =
-    nitro.options.cloudflare?.wrangler || ({} as WranglerConfig);
+  // Default configs
+  const defaults: WranglerConfig = {};
 
-  // Write wrangler.toml only if config is not empty
-  if (!inlineConfig || Object.keys(inlineConfig).length === 0) {
-    return;
+  // Compatibility date
+  defaults.compatibility_date =
+    nitro.options.compatibilityDate.cloudflare ||
+    nitro.options.compatibilityDate.default;
+
+  // Enable nodejs compatibility by default but disable wrangler transforms
+  defaults.compatibility_flags = ["nodejs_compat", "no_nodejs_compat_v2"];
+
+  if (isPages) {
+    // Pages
+    defaults.pages_build_output_dir = relative(
+      dirname(wranglerConfigPath),
+      nitro.options.output.publicDir
+    );
+  } else {
+    // Modules
+    defaults.main = relative(
+      wranglerConfigDir,
+      join(nitro.options.output.serverDir, "index.mjs")
+    );
+    defaults.assets = {
+      // @ts-expect-error
+      binding: "ASSETS",
+      directory: relative(
+        dirname(wranglerConfigPath),
+        nitro.options.output.publicDir
+      ),
+    };
   }
 
-  let configFromFile: WranglerConfig = {} as WranglerConfig;
-  const configPath = resolve(
-    nitro.options.rootDir,
-    inlineConfig.configPath || "wrangler.toml"
+  // Read user config
+  const userConfig = await resolveWranglerConfig(nitro.options.rootDir);
+
+  // (first argument takes precedence)
+  const wranglerConfig = mergeWranglerConfigs(
+    userConfig,
+    nitro.options.cloudflare?.wrangler,
+    defaults
+  );
+
+  // Write wrangler.json
+  await writeFile(
+    wranglerConfigPath,
+    JSON.stringify(wranglerConfig, null, 2),
+    true
   );
-  if (existsSync(configPath)) {
-    configFromFile = parseTOML<WranglerConfig>(
-      await fsp.readFile(configPath, "utf8")
+
+  // Write .wrangler/deploy/config.json (redirect file)
+  if (!nitro.options.cloudflare?.noWranglerDeployConfig) {
+    const configPath = join(
+      nitro.options.rootDir,
+      ".wrangler/deploy/config.json"
+    );
+    await writeFile(
+      configPath,
+      JSON.stringify({
+        configPath: relative(dirname(configPath), wranglerConfigPath),
+      }),
+      true
+    );
+  }
+}
+
+async function resolveWranglerConfig(dir: string): Promise<WranglerConfig> {
+  const jsonConfig = join(dir, "wrangler.json");
+  if (existsSync(jsonConfig)) {
+    const config = JSON.parse(
+      await readFile(join(dir, "wrangler.json"), "utf8")
+    ) as WranglerConfig;
+    return config;
+  }
+  const tomlConfig = join(dir, "wrangler.toml");
+  if (existsSync(tomlConfig)) {
+    const config = parseTOML<WranglerConfig>(
+      await readFile(join(dir, "wrangler.toml"), "utf8")
     );
+    return config;
   }
+  return {};
+}
 
-  const wranglerConfig: WranglerConfig = defu(configFromFile, inlineConfig);
+/**
+ * Merge wrangler configs (first argument takes precedence)
+ */
+function mergeWranglerConfigs(
+  ...configs: (WranglerConfig | undefined)[]
+): WranglerConfig {
+  // Merge configs
+  const merged = defu({}, ...configs) as WranglerConfig;
 
-  const wranglerPath = join(
-    isCI ? nitro.options.rootDir : nitro.options.buildDir,
-    "wrangler.toml"
-  );
+  // Normalize compatibility flags
+  if (merged.compatibility_flags) {
+    let flags = [...new Set(merged.compatibility_flags || [])];
+    if (flags.includes("no_nodejs_compat_v2")) {
+      flags = flags.filter((flag) => flag !== "nodejs_compat_v2");
+    }
+    merged.compatibility_flags = flags;
+  }
 
-  await fsp.writeFile(wranglerPath, stringifyTOML(wranglerConfig));
+  return merged;
 }