feat: detect target

Co-authored-by: Sebasiten Chopin <seb@nuxtjs.com>

packages/nitro/src/config.ts

@@ -1,7 +1,7 @@
 import { resolve } from 'path'
 import defu from 'defu'
 import { NuxtOptions } from '@nuxt/types'
-import { tryImport, LIB_DIR, resolvePath } from './utils'
+import { tryImport, LIB_DIR, resolvePath, detectTarget } from './utils'
 
 export type UnresolvedPath = string | ((SLSOptions) => string)
 
@@ -57,7 +57,7 @@ export function getoptions (nuxtOptions: NuxtOptions): SLSOptions {
     targetDir: null
   }
 
-  let target = process.env.NUXT_SLS_TARGET || nuxtOptions.serverless.target || 'node'
+  let target = process.env.NUXT_SLS_TARGET || nuxtOptions.serverless.target || detectTarget()
   if (typeof target === 'function') {
     target = target(nuxtOptions)
   }

packages/nitro/src/utils.ts

@@ -42,5 +42,17 @@ export function resolvePath (options: SLSOptions, path: UnresolvedPath, resolveB
   return resolve(resolveBase, typeof path === 'string' ? path : path(options))
 }
 
+export function detectTarget () {
+  if (process.env.NETLIFY) {
+    return 'netlify'
+  }
+
+  if (process.env.VERCEL_URL) {
+    return 'vercel'
+  }
+
+  return 'node'
+}
+
 export const LIB_DIR = resolve(__dirname, '../lib')
 export const RUNTIME_DIR = resolve(LIB_DIR, 'runtime')