feat(netlify): incremental static regeneration + swr (#540)

Author: danielroe

src/presets/netlify.ts

@@ -6,6 +6,7 @@ import type { Nitro } from '../types'
 // Netlify functions
 export const netlify = defineNitroPreset({
   extends: 'aws-lambda',
+  entry: '#internal/nitro/entries/netlify',
   output: {
     dir: '{{ rootDir }}/.netlify/functions-internal',
     publicDir: '{{ rootDir }}/dist'
@@ -80,6 +81,11 @@ async function writeRedirects (nitro: Nitro) {
   const redirectsPath = join(nitro.options.output.publicDir, '_redirects')
   let contents = '/* /.netlify/functions/server 200'
 
+  // Rewrite SWR and static paths to builder functions
+  for (const [key] of Object.entries(nitro.options.routes).filter(([_, value]) => value.swr || value.static)) {
+    contents = `${key.replace('/**', '/*')}\t/.netlify/builders/server 200\n` + contents
+  }
+
   for (const [key, value] of Object.entries(nitro.options.routes).filter(([_, value]) => value.redirect)) {
     const redirect = typeof value.redirect === 'string' ? { to: value.redirect } : value.redirect
     // TODO: update to 307 when netlify support 307/308

src/runtime/entries/netlify.ts

@@ -0,0 +1,59 @@
+import '#internal/nitro/virtual/polyfill'
+import type { Handler, HandlerResponse, HandlerContext, HandlerEvent } from '@netlify/functions/dist/main'
+import type { APIGatewayProxyEventHeaders } from 'aws-lambda'
+import { withQuery } from 'ufo'
+import { createRouter as createMatcher } from 'radix3'
+import { nitroApp } from '../app'
+import { useRuntimeConfig } from '../config'
+
+export const handler: Handler = async function handler (event, context) {
+  const config = useRuntimeConfig()
+  const routerOptions = createMatcher({ routes: config.nitro.routes })
+
+  const query = { ...event.queryStringParameters, ...event.multiValueQueryStringParameters }
+  const url = withQuery(event.path, query)
+  const routeOptions = routerOptions.lookup(url) || {}
+
+  if (routeOptions.static || routeOptions.swr) {
+    const builder = await import('@netlify/functions').then(r => r.builder || r.default.builder)
+    const ttl = typeof routeOptions.swr === 'number' ? routeOptions.swr : 60
+    const swrHandler = routeOptions.swr
+      ? ((event, context) => lambda(event, context).then(r => ({ ...r, ttl }))) as Handler
+      : lambda
+    return builder(swrHandler)(event, context) as any
+  }
+
+  return lambda(event, context)
+}
+
+async function lambda (event: HandlerEvent, context: HandlerContext): Promise<HandlerResponse> {
+  const query = { ...event.queryStringParameters, ...(event).multiValueQueryStringParameters }
+  const url = withQuery((event).path, query)
+  const method = (event).httpMethod || 'get'
+
+  const r = await nitroApp.localCall({
+    event,
+    url,
+    context,
+    headers: normalizeIncomingHeaders(event.headers),
+    method,
+    query,
+    body: event.body // TODO: handle event.isBase64Encoded
+  })
+
+  return {
+    statusCode: r.status,
+    headers: normalizeOutgoingHeaders(r.headers),
+    body: r.body.toString()
+  }
+}
+
+function normalizeIncomingHeaders (headers?: APIGatewayProxyEventHeaders) {
+  return Object.fromEntries(Object.entries(headers || {}).map(([key, value]) => [key.toLowerCase(), value!]))
+}
+
+function normalizeOutgoingHeaders (headers: Record<string, string | string[] | undefined>) {
+  return Object.fromEntries(Object.entries(headers)
+    .filter(([key]) => !['set-cookie'].includes(key))
+    .map(([k, v]) => [k, Array.isArray(v) ? v.join(',') : v!]))
+}

src/types/nitro.ts

@@ -68,6 +68,7 @@ export interface NitroConfig extends DeepPartial<NitroOptions> {
 
 export interface NitroRouteOption {
   swr?: boolean | number
+  static?: boolean
   redirect?: string | { to: string, statusCode?: 301 | 302 | 307 | 308 }
   headers?: Record<string, string>
   cors?: boolean

test/presets/netlify.test.ts

@@ -37,6 +37,7 @@ describe('nitro:preset:netlify', async () => {
       /rules/nested/*	/base	301
       /rules/redirect/obj	https://nitro.unjs.io/	308
       /rules/redirect	/base	301
+      /rules/static	/.netlify/builders/server 200
       /* /.netlify/functions/server 200"
     `)
     /* eslint-enable no-tabs */

test/tests.ts

@@ -38,6 +38,7 @@ export async function setupTest (preset) {
       '/rules/headers': { headers: { 'cache-control': 's-maxage=60' } },
       '/rules/cors': { cors: true, headers: { 'access-control-allowed-methods': 'GET' } },
       '/rules/redirect': { redirect: '/base' },
+      '/rules/static': { static: true },
       '/rules/redirect/obj': {
         redirect: { to: 'https://nitro.unjs.io/', statusCode: 308 }
       },