add a helper for how serverless function config is defined

Author: pieh

src/build/functions/server.ts

@@ -145,7 +145,7 @@ export const createServerHandler = async (ctx: PluginContext) => {
     await copyNextServerCode(ctx)
     await copyNextDependencies(ctx)
     await copyHandlerDependencies(ctx)
-    if (!ctx.useFrameworksAPI) {
+    if (ctx.serverHandlerConfigStrategy === 'manifest') {
       await writeHandlerManifest(ctx)
     }
     await writeHandlerFile(ctx)

src/build/plugin-context.ts

@@ -244,6 +244,10 @@ export class PluginContext {
     return './.netlify/dist/run/handlers/server.js'
   }
 
+  get serverHandlerConfigStrategy(): 'manifest' | 'inline' {
+    return this.useFrameworksAPI ? 'inline' : 'manifest'
+  }
+
   /**
    * Absolute path of the directory containing the files for deno edge functions
    * frameworks api: `.netlify/v1/edge-functions`