refactor: read runtime config from environment variables

- remove Next.js runtimeConfig usage in app config and test setup
- update runtime config helpers to read values from process.env
- update tests to stub required env vars with vi.stubEnv
- map mock config keys to environment variable names

Refs: LINK-2574

Author: jorilindell

next.config.js

@@ -24,23 +24,8 @@ const moduleExports = {
   sassOptions: {
     includePaths: ['src/styles'],
   },
-  publicRuntimeConfig: {
-    linkedEventsApiBaseUrl: process.env.NEXT_PUBLIC_LINKED_EVENTS_URL,
-    webStoreApiBaseUrl: process.env.NEXT_PUBLIC_WEB_STORE_API_BASE_URL,
-    attendanceListLoginMethods:
-      process.env.NEXT_PUBLIC_ATTENDANCE_LIST_LOGIN_METHODS,
-    signupsLoginMethods: process.env.NEXT_PUBLIC_SIGNUPS_LOGIN_METHODS,
-  },
-  serverRuntimeConfig: {
-    env: process.env.NEXT_ENV,
-    oidcApiTokensUrl: process.env.OIDC_API_TOKENS_URL,
-    oidcClientId: process.env.OIDC_CLIENT_ID,
-    oidcClientSecret: process.env.OIDC_CLIENT_SECRET,
-    oidcIssuer: process.env.OIDC_ISSUER,
-    oidcLinkedEventsApiScope: process.env.OIDC_LINKED_EVENTS_API_SCOPE,
-  },
   env: {
-    APP_VERSION: packageJson.version
+    APP_VERSION: packageJson.version,
   },
   output: 'standalone',
   eslint: {
@@ -64,7 +49,7 @@ module.exports = withSentryConfig(moduleExports, {
     },
     treeshake: {
       // Automatically tree-shake Sentry logger statements to reduce bundle size
-      removeDebugLogging: true
+      removeDebugLogging: true,
     },
     reactComponentAnnotation: {
       enabled: true,

src/setupTests.ts

@@ -21,16 +21,11 @@ if (typeof Blob !== 'undefined' && !Blob.prototype.stream) {
   } as () => ReadableStream;
 }
 
-import { setConfig } from 'next/config';
 import { expect, beforeAll, afterAll, afterEach, vi } from 'vitest';
 import * as matchers from 'vitest-axe/matchers';
 
-import config from '../next.config';
-
 import { server } from './tests/msw/server';
 
-setConfig(config);
-
 expect.extend(matchers);
 
 // Mock scrollTo function

src/utils/__tests__/getPublicRuntimeConfig.test.ts

@@ -1,5 +1,5 @@
+import { beforeEach, vi } from 'vitest';
 import getPublicRuntimeConfig from '../getPublicRuntimeConfig';
-import { mockConfig } from '../mockNextJsConfig';
 
 const publicRuntimeConfig = {
   linkedEventsApiBaseUrl: 'https://linkedevents-backend:8000/v1',
@@ -15,9 +15,28 @@ const expectedPublicRuntimeConfig = {
   signupsLoginMethods: ['helsinki_tunnus', 'helsinkiad'],
 };
 
+afterEach(() => {
+  vi.unstubAllEnvs();
+});
+
 describe('getPublicRuntimeConfig function', () => {
-  it('should return public runtime config', () => {
-    mockConfig(publicRuntimeConfig, {});
+  it('should return public runtime config', () => {
+    vi.stubEnv(
+      'NEXT_PUBLIC_LINKED_EVENTS_URL',
+      publicRuntimeConfig.linkedEventsApiBaseUrl
+    );
+    vi.stubEnv(
+      'NEXT_PUBLIC_WEB_STORE_API_BASE_URL',
+      publicRuntimeConfig.webStoreApiBaseUrl
+    );
+    vi.stubEnv(
+      'NEXT_PUBLIC_ATTENDANCE_LIST_LOGIN_METHODS',
+      publicRuntimeConfig.attendanceListLoginMethods
+    );
+    vi.stubEnv(
+      'NEXT_PUBLIC_SIGNUPS_LOGIN_METHODS',
+      publicRuntimeConfig.signupsLoginMethods
+    );
     expect(getPublicRuntimeConfig()).toEqual(expectedPublicRuntimeConfig);
   });
 
@@ -29,7 +48,22 @@ describe('getPublicRuntimeConfig function', () => {
   it.each(cases)(
     'should throw error if and public runtime variable is missing',
     (publicRuntimeConfig) => {
-      mockConfig(publicRuntimeConfig, {});
+      vi.stubEnv(
+        'NEXT_PUBLIC_LINKED_EVENTS_URL',
+        publicRuntimeConfig.linkedEventsApiBaseUrl
+      );
+      vi.stubEnv(
+        'NEXT_PUBLIC_WEB_STORE_API_BASE_URL',
+        publicRuntimeConfig.webStoreApiBaseUrl
+      );
+      vi.stubEnv(
+        'NEXT_PUBLIC_ATTENDANCE_LIST_LOGIN_METHODS',
+        publicRuntimeConfig.attendanceListLoginMethods
+      );
+      vi.stubEnv(
+        'NEXT_PUBLIC_SIGNUPS_LOGIN_METHODS',
+        publicRuntimeConfig.signupsLoginMethods
+      );
       expect(getPublicRuntimeConfig).toThrow(
         'Invalid configuration. Some required public runtime variable are missing'
       );

src/utils/__tests__/getServerRuntimeConfig.test.ts

@@ -1,5 +1,5 @@
+import { beforeEach, vi } from 'vitest';
 import getServerRuntimeConfig from '../getServerRuntimeConfig';
-import { mockConfig } from '../mockNextJsConfig';
 
 const serverRuntimeConfig = {
   env: 'development',
@@ -11,9 +11,21 @@ const serverRuntimeConfig = {
   oidcLinkedEventsApiScope: 'linkedevents',
 };
 
+afterEach(() => {
+  vi.unstubAllEnvs();
+});
+
 describe('getServerRuntimeConfig function', () => {
-  it('should return server runtime config', () => {
-    mockConfig({}, serverRuntimeConfig);
+  it('should return server runtime config', () => {
+    vi.stubEnv('NEXT_ENV', serverRuntimeConfig.env);
+    vi.stubEnv('OIDC_API_TOKENS_URL', serverRuntimeConfig.oidcApiTokensUrl);
+    vi.stubEnv('OIDC_CLIENT_ID', serverRuntimeConfig.oidcClientId);
+    vi.stubEnv('OIDC_CLIENT_SECRET', serverRuntimeConfig.oidcClientSecret);
+    vi.stubEnv('OIDC_ISSUER', serverRuntimeConfig.oidcIssuer);
+    vi.stubEnv(
+      'OIDC_LINKED_EVENTS_API_SCOPE',
+      serverRuntimeConfig.oidcLinkedEventsApiScope
+    );
     expect(getServerRuntimeConfig()).toEqual(serverRuntimeConfig);
   });
 
@@ -29,7 +41,15 @@ describe('getServerRuntimeConfig function', () => {
   it.each(cases)(
     'should throw error if an server runtime variable is missing',
     (serverRuntimeConfig) => {
-      mockConfig({}, serverRuntimeConfig);
+      vi.stubEnv('NEXT_ENV', serverRuntimeConfig.env);
+      vi.stubEnv('OIDC_API_TOKENS_URL', serverRuntimeConfig.oidcApiTokensUrl);
+      vi.stubEnv('OIDC_CLIENT_ID', serverRuntimeConfig.oidcClientId);
+      vi.stubEnv('OIDC_CLIENT_SECRET', serverRuntimeConfig.oidcClientSecret);
+      vi.stubEnv('OIDC_ISSUER', serverRuntimeConfig.oidcIssuer);
+      vi.stubEnv(
+        'OIDC_LINKED_EVENTS_API_SCOPE',
+        serverRuntimeConfig.oidcLinkedEventsApiScope
+      );
       expect(getServerRuntimeConfig).toThrow(
         'Invalid configuration. Some required server runtime variable are missing'
       );

src/utils/getPublicRuntimeConfig.ts

@@ -1,18 +1,18 @@
-import getConfig from 'next/config';
-
-import { parseLoginMethods } from "../constants";
+import { parseLoginMethods } from '../constants';
 
 const getPublicRuntimeConfig = () => {
-  const {
-    publicRuntimeConfig: {
-      linkedEventsApiBaseUrl,
-      webStoreApiBaseUrl,
-      attendanceListLoginMethods,
-      signupsLoginMethods
-    },
-  } = getConfig();
+  const linkedEventsApiBaseUrl = process.env.NEXT_PUBLIC_LINKED_EVENTS_URL;
+  const webStoreApiBaseUrl = process.env.NEXT_PUBLIC_WEB_STORE_API_BASE_URL;
+  const attendanceListLoginMethods =
+    process.env.NEXT_PUBLIC_ATTENDANCE_LIST_LOGIN_METHODS;
+  const signupsLoginMethods = process.env.NEXT_PUBLIC_SIGNUPS_LOGIN_METHODS;
 
-  if (!linkedEventsApiBaseUrl || !webStoreApiBaseUrl || !attendanceListLoginMethods || !signupsLoginMethods) {
+  if (
+    !linkedEventsApiBaseUrl ||
+    !webStoreApiBaseUrl ||
+    !attendanceListLoginMethods ||
+    !signupsLoginMethods
+  ) {
     throw new Error(
       'Invalid configuration. Some required public runtime variable are missing'
     );

src/utils/getServerRuntimeConfig.ts

@@ -1,16 +1,10 @@
-import getConfig from 'next/config';
-
 const getServerRuntimeConfig = () => {
-  const {
-    serverRuntimeConfig: {
-      env,
-      oidcApiTokensUrl,
-      oidcClientId,
-      oidcClientSecret,
-      oidcIssuer,
-      oidcLinkedEventsApiScope,
-    },
-  } = getConfig();
+  const env = process.env.NEXT_ENV;
+  const oidcApiTokensUrl = process.env.OIDC_API_TOKENS_URL;
+  const oidcClientId = process.env.OIDC_CLIENT_ID;
+  const oidcClientSecret = process.env.OIDC_CLIENT_SECRET;
+  const oidcIssuer = process.env.OIDC_ISSUER;
+  const oidcLinkedEventsApiScope = process.env.OIDC_LINKED_EVENTS_API_SCOPE;
 
   if (
     !env ||

src/utils/mockNextJsConfig.ts

@@ -1,12 +1,33 @@
-import * as nextConfig from 'next/config';
+import { vi } from 'vitest';
 
 export const mockConfig = (
   publicRuntimeConfig: Record<string, string>,
   serverRuntimeConfig: Record<string, string>
 ) => {
-  nextConfig.setConfig({
-    publicRuntimeConfig,
-    serverRuntimeConfig,
+  const publicEnvMap: Record<string, string> = {
+    linkedEventsApiBaseUrl: 'NEXT_PUBLIC_LINKED_EVENTS_URL',
+    webStoreApiBaseUrl: 'NEXT_PUBLIC_WEB_STORE_API_BASE_URL',
+    attendanceListLoginMethods: 'NEXT_PUBLIC_ATTENDANCE_LIST_LOGIN_METHODS',
+    signupsLoginMethods: 'NEXT_PUBLIC_SIGNUPS_LOGIN_METHODS',
+  };
+
+  Object.entries(publicRuntimeConfig).forEach(([key, value]) => {
+    const envKey = publicEnvMap[key] || `NEXT_PUBLIC_${key.toUpperCase()}`;
+    vi.stubEnv(envKey, value);
+  });
+
+  const serverEnvMap: Record<string, string> = {
+    env: 'NEXT_ENV',
+    oidcApiTokensUrl: 'OIDC_API_TOKENS_URL',
+    oidcClientId: 'OIDC_CLIENT_ID',
+    oidcClientSecret: 'OIDC_CLIENT_SECRET',
+    oidcIssuer: 'OIDC_ISSUER',
+    oidcLinkedEventsApiScope: 'OIDC_LINKED_EVENTS_API_SCOPE',
+  };
+
+  Object.entries(serverRuntimeConfig).forEach(([key, value]) => {
+    const envKey = serverEnvMap[key] || key.toUpperCase();
+    vi.stubEnv(envKey, value);
   });
 };