feat: ✨ add rootdirectory option to configure custom public folder root for __ENV.js

src/configure.spec.ts

@@ -41,6 +41,7 @@ describe('configureRuntimeEnv()', () => {
 
   it('should call the helper methods with options', () => {
     configureRuntimeEnv({
+      rootdirectory: 'rootdirectory/',
       subdirectory: 'subdirectory/',
     });
 
@@ -51,7 +52,10 @@ describe('configureRuntimeEnv()', () => {
       {
         NEXT_PUBLIC_FOO: 'foo',
       },
-      'subdirectory/',
+      {
+        rootdirectory: 'rootdirectory/',
+        subdirectory: 'subdirectory/',
+      },
     );
   });
 });

src/configure.ts

@@ -2,6 +2,11 @@ import { getPublicEnv } from './helpers/get-public-env';
 import { writeBrowserEnv } from './helpers/write-browser-env';
 
 export type ConfigureRuntimeEnvOptions = {
+  /**
+   * The rootdirectory of `/public` where the `__ENV.js` file should be written
+   * eg. `rootdirectory/`to.
+   */
+  rootdirectory?: string;
   /**
    * The subdirectory of `/public` where the `__ENV.js` file should be written
    * eg. `subdirectory/`to.
@@ -25,5 +30,5 @@ export type ConfigureRuntimeEnvOptions = {
 export function configureRuntimeEnv(options?: ConfigureRuntimeEnvOptions) {
   const publicEnv = getPublicEnv();
 
-  writeBrowserEnv(publicEnv, options?.subdirectory);
+  writeBrowserEnv(publicEnv, options);
 }

src/helpers/write-browser-env.spec.ts

@@ -69,13 +69,30 @@ describe('writeBrowserEnv()', () => {
     fs.rmSync(file);
   });
 
+  it('should write to a rootdirectory', () => {
+    const fileInRootdirectory = `${base}/rootdirectory/public/__ENV.js`;
+    const messageWithRootdirectory = `- ${chalk.green(
+      `ready`,
+    )} [next-runtime-env] wrote browser runtime environment variables to '${fileInRootdirectory}'.`;
+
+    writeBrowserEnv({}, { rootdirectory: 'rootdirectory/' });
+
+    expect(infoSpy).toHaveBeenCalledWith(messageWithRootdirectory);
+
+    const content = fs.readFileSync(fileInRootdirectory).toString();
+
+    expect(content).toEqual('window.__ENV = {};');
+
+    fs.rmSync(fileInRootdirectory);
+  });
+
   it('should write to a subdirectory', () => {
     const fileInSubdirectory = `${path}/subdirectory/__ENV.js`;
     const messageWithSubdirectory = `- ${chalk.green(
       `ready`,
     )} [next-runtime-env] wrote browser runtime environment variables to '${fileInSubdirectory}'.`;
 
-    writeBrowserEnv({}, 'subdirectory/');
+    writeBrowserEnv({}, { subdirectory: 'subdirectory/' });
 
     expect(infoSpy).toHaveBeenCalledWith(messageWithSubdirectory);
 

src/helpers/write-browser-env.ts

@@ -4,14 +4,18 @@ import path from 'path';
 import { type ProcessEnv } from '../typings/process-env';
 import * as log from '../utils/log';
 import { getBrowserEnvScript } from './get-browser-env-script';
+import { ConfigureRuntimeEnvOptions } from '../configure';
 
 /**
  * Writes the environment variables to the public __ENV.js file and make them
  * accessible under `window.__ENV`.
  */
-export function writeBrowserEnv(env: ProcessEnv, subdirectory = '') {
+export function writeBrowserEnv(
+  env: ProcessEnv,
+  options?: ConfigureRuntimeEnvOptions,
+) {
   const base = fs.realpathSync(process.cwd());
-  const file = `${base}/public/${subdirectory}__ENV.js`;
+  const file = `${base}/${options?.rootdirectory ?? ''}public/${options?.subdirectory ?? ''}__ENV.js`;
 
   const content = getBrowserEnvScript(env);
 

undefinedpublic/subdirectory/__ENV.js

@@ -0,0 +1 @@
+window.__ENV = {};

undefinedpublic/undefined__ENV.js

@@ -0,0 +1 @@
+window.__ENV = {"NEXT_PUBLIC_FOO":"foo","NEXT_PUBLIC_BAR":"bar","NEXT_PUBLIC_BAZ":"baz"};