♻️ Add env variable validation

src/env.js

@@ -0,0 +1,66 @@
+const { z } = require('zod');
+const { createEnv } = require('@t3-oss/env-nextjs');
+
+const portSchema = z.string().regex(/\d+/).transform(Number).optional()
+const envSchema = z.enum(["development", "test", "production"]);
+
+const env = createEnv({
+  /**
+   * Specify your server-side environment variables schema here. This way you can ensure the app
+   * isn't built with invalid env vars.
+   */
+  server: {
+    DATABASE_URL: z.string().url(),
+    NODE_ENV: envSchema,
+    NEXTAUTH_SECRET:
+      process.env.NODE_ENV === "production"
+        ? z.string().min(1)
+        : z.string().min(1).optional(),
+    NEXTAUTH_URL: z.preprocess(
+      // This makes Vercel deployments not fail if you don't set NEXTAUTH_URL
+      // Since NextAuth.js automatically uses the VERCEL_URL if present.
+      (str) => process.env.VERCEL_URL ?? str,
+      // VERCEL_URL doesn't include `https` so it cant be validated as a URL
+      process.env.VERCEL ? z.string().min(1) : z.string().url(),
+    ),
+    DEFAULT_COLOR_SCHEME: z.enum(['light', 'dark']).optional().default('light'),
+    DOCKER_HOST: z.string().optional(),
+    DOCKER_PORT: z.string().regex(/\d+/).transform(Number).optional(),
+    PORT: portSchema
+  },
+
+  /**
+   * Specify your client-side environment variables schema here. This way you can ensure the app
+   * isn't built with invalid env vars. To expose them to the client, prefix them with
+   * `NEXT_PUBLIC_`.
+   */
+  client: {
+    // NEXT_PUBLIC_CLIENTVAR: z.string().min(1),
+    NEXT_PUBLIC_PORT: portSchema,
+    NEXT_PUBLIC_NODE_ENV: envSchema
+  },
+
+  /**
+   * You can't destruct `process.env` as a regular object in the Next.js edge runtimes (e.g.
+   * middlewares) or client-side so we need to destruct manually.
+   */
+  runtimeEnv: {
+    DATABASE_URL: process.env.DATABASE_URL,
+    NODE_ENV: process.env.NODE_ENV,
+    NEXTAUTH_SECRET: process.env.NEXTAUTH_SECRET,
+    NEXTAUTH_URL: process.env.NEXTAUTH_URL,
+    NEXT_PUBLIC_DISABLE_EDIT_MODE: process.env.DISABLE_EDIT_MODE,
+    DISABLE_EDIT_MODE: process.env.DISABLE_EDIT_MODE,
+    DEFAULT_COLOR_SCHEME: process.env.DEFAULT_COLOR_SCHEME,
+    DOCKER_HOST: process.env.DOCKER_HOST,
+    DOCKER_PORT: process.env.DOCKER_PORT,
+    VERCEL_URL: process.env.VERCEL_URL,
+    PORT: process.env.PORT,
+    NEXT_PUBLIC_PORT: process.env.PORT,
+    NEXT_PUBLIC_NODE_ENV: process.env.NODE_ENV
+  },
+});
+
+module.exports = {
+  env
+}