feat: defineRenderHandler (#395)

src/imports.ts

@@ -12,7 +12,8 @@ export const nitroImports: Preset[] = [
       'useStorage',
       'useNitroApp',
       'defineNitroPlugin',
-      'nitroPlugin'
+      'nitroPlugin',
+      'defineRenderHandler'
     ]
   },
   {

src/rollup/plugins/handlers.ts

@@ -1,5 +1,5 @@
 import { hash } from 'ohash'
-import type { Nitro, NitroEventHandler } from '../../types'
+import type { Nitro } from '../../types'
 import { virtual } from './virtual'
 
 const unique = (arr: any[]) => Array.from(new Set(arr))

src/runtime/index.ts

@@ -3,3 +3,4 @@ export { useRuntimeConfig } from './config'
 export * from './cache'
 export { useNitroApp } from './app'
 export * from './plugin'
+export * from './renderer'

src/runtime/renderer.ts

@@ -0,0 +1,46 @@
+import { CompatibilityEvent, eventHandler } from 'h3'
+
+export interface RenderResponse {
+  body: string,
+  statusCode: number,
+  statusMessage: string,
+  headers: Record<string, string>
+}
+
+export type RenderHandler = (event: CompatibilityEvent) => Partial<RenderResponse> | Promise<Partial<RenderResponse>>
+
+export function defineRenderHandler (handler: RenderHandler) {
+  return eventHandler(async (event) => {
+    // TODO: Use serve-placeholder
+    if (event.req.url.endsWith('/favicon.ico')) {
+      event.res.setHeader('Content-Type', 'image/x-icon')
+      event.res.end('data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7')
+      return
+    }
+
+    const response = await handler(event)
+
+    // TODO: Warn if response is already handled
+
+    // TODO: Caching support
+
+    // Send headers
+    if (!event.res.headersSent && response.headers) {
+      for (const header in response.headers) {
+        event.res.setHeader(header, response.headers[header])
+      }
+      if (response.statusCode) {
+        event.res.statusCode = response.statusCode
+      }
+      if (response.statusMessage) {
+        event.res.statusMessage = response.statusMessage
+      }
+    }
+
+    // Send response body
+    if (!event.res.writableEnded) {
+      // TODO: Warn if body is not string
+      event.res.end(typeof response.body === 'string' ? response.body : JSON.stringify(response.body))
+    }
+  })
+}