feat: force port 3000 to make Next.js abort startup on multiple instances clashing on same port

.env.local.example

@@ -25,3 +25,4 @@ SEAMLESS_LOGIN_FI="http://www.example.fi/updatelogin"
 SEAMLESS_LOGIN_NO="http://www.example.no/updatelogin"
 SEAMLESS_LOGIN_SV="http://www.example.se/updatelogin"
 WEBVIEW_ENCRYPTION_KEY="MTIzNDU2Nzg5MDEyMzQ1Njc4OTAxMjM0NTY3ODkwMTI="
+

env/client.ts

@@ -2,7 +2,11 @@ import { createEnv } from "@t3-oss/env-nextjs"
 import { z } from "zod"
 
 export const env = createEnv({
-  client: { NEXT_PUBLIC_PORT: z.string().optional() },
+  client: {
+    NEXT_PUBLIC_PORT: z.string().default("3000"),
+  },
   emptyStringAsUndefined: true,
-  runtimeEnv: { NEXT_PUBLIC_PORT: process.env.PORT },
+  runtimeEnv: {
+    NEXT_PUBLIC_PORT: process.env.NEXT_PUBLIC_PORT,
+  },
 })

lib/trpc/Provider.tsx

@@ -10,6 +10,8 @@ import { transformer } from "@/server/transformer"
 import { trpc } from "./client"
 
 function initializeTrpcClient() {
+  // Locally we set nextjs to run on port to 3000 so that we always guarantee
+  //  that trpc and next are running on the same port.
   return trpc.createClient({
     links: [
       httpBatchLink({

package.json

@@ -7,7 +7,7 @@
     "prebuild": "npm run lint",
     "build": "next build",
     "predev": "rm -rf .next",
-    "dev": "next dev",
+    "dev": "PORT=3000 NEXT_PUBLIC_PORT=3000 next dev",
     "prelint": "rm -rf .next",
     "lint": "next lint --max-warnings 0 && tsc",
     "prelint:fix": "rm -rf .next",