feat(ui): auto proxy backend (#2238)

packages/ui/vite.config.js

@@ -3,21 +3,36 @@ import react from '@vitejs/plugin-react'
 import { resolve } from 'path'
 import dotenv from 'dotenv'
 
-dotenv.config()
-
-export default defineConfig({
-    plugins: [react()],
-    resolve: {
-        alias: {
-            '@': resolve(__dirname, 'src')
+export default defineConfig(async ({ mode }) => {
+    let proxy = undefined
+    if (mode === 'development') {
+        const serverPort = parseInt(dotenv.config({ processEnv: {}, path: '../server/.env' }).parsed?.['PORT'])
+        if (!Number.isNaN(serverPort) && serverPort > 0 && serverPort < 65535) {
+            proxy = {
+                '/api': {
+                    target: `http://localhost:${serverPort}`,
+                    changeOrigin: true
+                }
+            }
+        }
+    }
+    dotenv.config()
+    return {
+        plugins: [react()],
+        resolve: {
+            alias: {
+                '@': resolve(__dirname, 'src')
+            }
+        },
+        root: resolve(__dirname),
+        build: {
+            outDir: './build'
+        },
+        server: {
+            open: true,
+            proxy,
+            port: process.env.VITE_PORT ?? 8080,
+            host: process.env.VITE_HOST
         }
-    },
-    root: resolve(__dirname),
-    build: {
-        outDir: './build'
-    },
-    server: {
-        open: true,
-        port: process.env.VITE_PORT ?? 8080
     }
 })