feat: support app config (#1022)

src/build.ts

@@ -5,7 +5,7 @@ import * as rollup from "rollup";
 import fse from "fs-extra";
 import { defu } from "defu";
 import { watch } from "chokidar";
-import { scanDirExports } from "unimport";
+import { genTypeImport } from "knitwork";
 import { debounce } from "perfect-debounce";
 import type { TSConfig } from "pkg-types";
 import type { RollupError } from "rollup";
@@ -128,6 +128,26 @@ export async function writeTypes(nitro: Nitro) {
     "  }",
     "}",
     ...autoImportedTypes,
+    `
+// App Config
+import type { Defu } from 'defu'
+
+${nitro.options.appConfigFiles
+  .map((file, index) =>
+    genTypeImport(file.replace(/\.\w+$/, ""), [
+      { name: "default", as: `appConfig${index}` },
+    ])
+  )
+  .join("\n")}
+
+type UserAppConfig = Defu<{}, [${nitro.options.appConfigFiles
+      .map((_, index: number) => `typeof appConfig${index}`)
+      .join(", ")}]>
+
+declare module 'nitropack' {
+  interface AppConfig extends UserAppConfig {}
+}
+    `,
     // Makes this a module for augmentation purposes
     "export {}",
   ];

src/imports.ts

@@ -15,6 +15,7 @@ export const nitroImports: Preset[] = [
       "nitroPlugin",
       "defineRenderHandler",
       "getRouteRules",
+      "useAppConfig",
     ],
   },
 ];

src/options.ts

@@ -8,7 +8,12 @@ import escapeRE from "escape-string-regexp";
 import { withLeadingSlash, withoutTrailingSlash, withTrailingSlash } from "ufo";
 import { isTest, isDebug } from "std-env";
 import { findWorkspaceDir } from "pkg-types";
-import { resolvePath, detectTarget, provideFallbackValues } from "./utils";
+import {
+  resolvePath,
+  resolveFile,
+  detectTarget,
+  provideFallbackValues,
+} from "./utils";
 import type {
   NitroConfig,
   NitroOptions,
@@ -24,6 +29,8 @@ const NitroDefaults: NitroConfig = {
   debug: isDebug,
   logLevel: isTest ? 1 : 3,
   runtimeConfig: { app: {}, nitro: {} },
+  appConfig: {},
+  appConfigFiles: [],
 
   // Dirs
   scanDirs: [],
@@ -238,6 +245,19 @@ export async function loadOptions(
     );
   }
 
+  // Normalize app.config file paths
+  options.appConfigFiles = options.appConfigFiles
+    .map((file) => resolveFile(resolvePath(file, options)))
+    .filter(Boolean);
+
+  // Detect app.config from scanDirs
+  for (const dir of options.scanDirs) {
+    const configFile = resolveFile("app.config", dir);
+    if (configFile && !options.appConfigFiles.includes(configFile)) {
+      options.appConfigFiles.push(configFile);
+    }
+  }
+
   // Backward compatibility for options.routes
   options.routeRules = defu(options.routeRules, (options as any).routes || {});
 

src/rollup/config.ts

@@ -34,6 +34,7 @@ import { esbuild } from "./plugins/esbuild";
 import { raw } from "./plugins/raw";
 import { storage } from "./plugins/storage";
 import { importMeta } from "./plugins/import-meta";
+import { appConfig } from "./plugins/app-config";
 
 export type RollupConfig = InputOptions & { output: OutputOptions };
 
@@ -245,6 +246,9 @@ export const getRollupConfig = (nitro: Nitro) => {
   // Storage
   rollupConfig.plugins.push(storage(nitro));
 
+  // App.config
+  rollupConfig.plugins.push(appConfig(nitro));
+
   // Handlers
   rollupConfig.plugins.push(handlers(nitro));
 

src/rollup/plugins/app-config.ts

@@ -0,0 +1,25 @@
+import { genImport } from "knitwork";
+import type { Nitro } from "../../types";
+import { virtual } from "./virtual";
+
+export function appConfig(nitro: Nitro) {
+  return virtual(
+    {
+      "#internal/nitro/virtual/app-config": () => `
+import { defuFn } from 'defu';
+
+const inlineAppConfig = ${JSON.stringify(nitro.options.appConfig, null, 2)};
+
+${nitro.options.appConfigFiles
+  .map((file, i) => genImport(file, "appConfig" + i) + ";")
+  .join("\n")}
+
+export const appConfig = defuFn(${[
+        ...nitro.options.appConfigFiles.map((_, i) => "appConfig" + i),
+        "inlineAppConfig",
+      ].join(", ")});
+      `,
+    },
+    nitro.vfs
+  );
+}

src/runtime/config.ts

@@ -1,23 +1,35 @@
 import destr from "destr";
 import { snakeCase } from "scule";
+import { appConfig as _appConfig } from "#internal/nitro/virtual/app-config";
 
-// Bundled runtime config (injected by nitro)
+// Runtime config
 const _runtimeConfig = process.env.RUNTIME_CONFIG as any;
-
 const ENV_PREFIX = "NITRO_";
 const ENV_PREFIX_ALT =
   _runtimeConfig.nitro.envPrefix ?? process.env.NITRO_ENV_PREFIX ?? "_";
+overrideConfig(_runtimeConfig);
+
+const runtimeConfig = deepFreeze(_runtimeConfig);
+export default runtimeConfig; // TODO: Remove in next major version
+export const useRuntimeConfig = () => runtimeConfig;
+
+// App config
+const appConfig = deepFreeze(_appConfig);
+export const useAppConfig = () => appConfig;
+
+// --- Utils ---
 
-// Allow override from process.env and deserialize
-const getEnv = (key: string) => {
+function getEnv(key: string) {
   const envKey = snakeCase(key).toUpperCase();
   return destr(
     process.env[ENV_PREFIX + envKey] ?? process.env[ENV_PREFIX_ALT + envKey]
   );
-};
+}
+
 function isObject(input: unknown) {
   return typeof input === "object" && !Array.isArray(input);
 }
+
 function overrideConfig(obj: object, parentKey = "") {
   for (const key in obj) {
     const subKey = parentKey ? `${parentKey}_${key}` : key;
@@ -32,14 +44,7 @@ function overrideConfig(obj: object, parentKey = "") {
     }
   }
 }
-overrideConfig(_runtimeConfig);
-
-// Named exports
-const config = deepFreeze(_runtimeConfig);
-export const useRuntimeConfig = () => config;
-export default config;
 
-// Utils
 function deepFreeze(object: Record<string, any>) {
   const propNames = Object.getOwnPropertyNames(object);
   for (const name of propNames) {

src/runtime/index.ts

@@ -1,5 +1,5 @@
 export { useStorage } from "#internal/nitro/virtual/storage";
-export { useRuntimeConfig } from "./config";
+export { useRuntimeConfig, useAppConfig } from "./config";
 export * from "./cache";
 export { useNitroApp } from "./app";
 export * from "./plugin";

src/runtime/virtual/app-config.d.ts

@@ -0,0 +1,3 @@
+import type { AppConfig } from "nitropack";
+
+export const appConfig: AppConfig;

src/types/nitro.ts

@@ -87,6 +87,10 @@ export interface NitroConfig
   rollupConfig?: Partial<RollupConfig>;
 }
 
+export interface AppConfig {
+  [key: string]: any;
+}
+
 export interface PublicAssetDir {
   baseURL?: string;
   fallthrough?: boolean;
@@ -154,6 +158,8 @@ export interface NitroOptions extends PresetOptions {
     };
     [key: string]: any;
   };
+  appConfig: AppConfig;
+  appConfigFiles: string[];
 
   // Dirs
   workspaceDir: string;

src/utils/index.ts

@@ -77,6 +77,23 @@ export function resolvePath(
   return resolve(base || nitroOptions.srcDir, path);
 }
 
+export function resolveFile(
+  path: string,
+  base = ".",
+  extensions = [".js", ".ts", ".mjs", ".cjs", ".json"]
+): string | undefined {
+  path = resolve(base, path);
+  if (existsSync(path)) {
+    return path;
+  }
+  for (const ext of extensions) {
+    const p = path + ext;
+    if (existsSync(p)) {
+      return p;
+    }
+  }
+}
+
 export function replaceAll(input: string, from: string, to: string) {
   return input.replace(new RegExp(from, "g"), to);
 }

test/fixture/app.config.ts

@@ -0,0 +1,3 @@
+export default {
+  "app-config": true,
+};

test/fixture/nitro.config.ts

@@ -20,6 +20,10 @@ export default defineNitroConfig({
       dir: "files",
     },
   ],
+  appConfig: {
+    "nitro-config": true,
+  },
+  appConfigFiles: ["~/server.config.ts"],
   publicAssets: [
     {
       baseURL: "build",

test/fixture/routes/app-config.ts

@@ -0,0 +1,7 @@
+export default eventHandler(() => {
+  const appConfig = useAppConfig();
+
+  return {
+    appConfig,
+  };
+});

test/fixture/server.config.ts

@@ -0,0 +1,3 @@
+export default {
+  "server-config": true,
+};

test/tests.ts

@@ -317,6 +317,21 @@ export function testNitro(
     }
   }
 
+  it("app config", async () => {
+    const { data } = await callHandler({
+      url: "/app-config",
+    });
+    expect(data).toMatchInlineSnapshot(`
+      {
+        "appConfig": {
+          "app-config": true,
+          "nitro-config": true,
+          "server-config": true,
+        },
+      }
+    `);
+  });
+
   if (ctx.nitro!.options.timing) {
     it("set server timing header", async () => {
       const { data, status, headers } = await callHandler({