Merge pull request #70 from nitrictech/feature/multiple-handlers

feat: allow multiple handlers in faas functions
nitrictech · Oct 10, 2021 · 72cfe34 · 72cfe34
2 parents efc414a + cbffb6e
commit 72cfe34
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Showing 2 changed files with 48 additions and 39 deletions.
diff --git a/src/faas/v0/start.ts b/src/faas/v0/start.ts
@@ -22,14 +22,21 @@ import {
   HeaderValue,
   TriggerResponse,
   TopicResponseContext,
-  InitRequest
+  InitRequest,
 } from '@nitric/api/proto/faas/v1/faas_pb';
 
-import { EventMiddleware, GenericMiddleware, HttpMiddleware, TriggerContext, TriggerMiddleware } from '.';
-
+import {
+  createHandler,
+  EventMiddleware,
+  GenericMiddleware,
+  HttpContext,
+  HttpMiddleware,
+  TriggerContext,
+  TriggerMiddleware,
+} from '.';
 
 /**
- * 
+ *
  */
 class Faas {
   private httpHandler?: HttpMiddleware;
@@ -39,16 +46,16 @@ class Faas {
   /**
    * Add an event handler to this Faas server
    */
-  event(handler: EventMiddleware): Faas {
-    this.eventHandler = handler;
+  event(...handlers: EventMiddleware[]): Faas {
+    this.eventHandler = createHandler(...handlers);
     return this;
   }
 
   /**
    * Add a http handler to this Faas server
    */
-  http(handler: HttpMiddleware): Faas {
-    this.httpHandler = handler;
+  http(...handlers: HttpMiddleware[]): Faas {
+    this.httpHandler = createHandler(...handlers);
     return this;
   }
 
@@ -69,21 +76,21 @@ class Faas {
   /**
    * Start the Faas server
    */
-  async start(handler?: TriggerMiddleware): Promise<void> {
-    this.anyHandler = handler;
-    if(!this.httpHandler && !this.eventHandler && !this.anyHandler) {
-      throw new Error("A handler function must be provided.");
+  async start(...handlers: TriggerMiddleware[]): Promise<void> {
+    this.anyHandler = handlers.length && createHandler(...handlers);
+    if (!this.httpHandler && !this.eventHandler && !this.anyHandler) {
+      throw new Error('A handler function must be provided.');
     }
 
     // Actually start the server...
     const faasClient = new FaasServiceClient(
       SERVICE_BIND,
       grpc.ChannelCredentials.createInsecure()
     );
-  
+
     // Begin Bi-Di streaming
     const faasStream = faasClient.triggerStream();
-  
+
     faasStream.on('data', async (message: ServerMessage) => {
       // We have an init response from the membrane
       if (message.hasInitResponse()) {
@@ -94,39 +101,43 @@ class Faas {
         // We want to handle a function here...
         const triggerRequest = message.getTriggerRequest();
         const responseMessage = new ClientMessage();
-  
+
         responseMessage.setId(message.getId());
-  
+
         try {
           const ctx = TriggerContext.fromGrpcTriggerRequest(triggerRequest);
 
           let handler: GenericMiddleware<TriggerContext> = undefined;
-          let triggerType = "Unknown";
+          let triggerType = 'Unknown';
           if (ctx.http) {
-            triggerType = "HTTP";
+            triggerType = 'HTTP';
             handler = this.getHttpHandler() as GenericMiddleware<TriggerContext>;
           } else if (ctx.event) {
-            triggerType = "Event";
+            triggerType = 'Event';
             handler = this.getEventHandler() as GenericMiddleware<TriggerContext>;
           } else {
-            console.error(`received an unexpected trigger type, are you using an outdated version of the SDK?`);
+            console.error(
+              `received an unexpected trigger type, are you using an outdated version of the SDK?`
+            );
           }
-          
-          if(!handler) {
+
+          if (!handler) {
             // No handler defined for the trigger type received.
             console.error(`no handler defined for ${triggerType} triggers`);
             faasStream.cancel();
           }
-          
+
           const result = await handler(ctx, async (ctx) => ctx);
-          responseMessage.setTriggerResponse(TriggerContext.toGrpcTriggerResponse(result));
+          responseMessage.setTriggerResponse(
+            TriggerContext.toGrpcTriggerResponse(result)
+          );
         } catch (e) {
           console.error(e);
           // generic error handling
           console.error(e);
           const triggerResponse = new TriggerResponse();
           responseMessage.setTriggerResponse(triggerResponse);
-  
+
           if (triggerRequest.hasHttp()) {
             const httpResponse = new HttpResponseContext();
             triggerResponse.setHttp(httpResponse);
@@ -140,7 +151,7 @@ class Faas {
             triggerResponse.setData('Internal Server Error');
           } else if (triggerRequest.hasTopic()) {
             const topicResponse = new TopicResponseContext();
-  
+
             topicResponse.setSuccess(false);
             triggerResponse.setTopic(topicResponse);
             triggerResponse.setData('Internal Server Error');
@@ -150,13 +161,13 @@ class Faas {
         faasStream.write(responseMessage);
       }
     });
-  
+
     // Let the membrane know we're ready to start
     const initRequest = new InitRequest();
     const initMessage = new ClientMessage();
     initMessage.setInitRequest(initRequest);
     faasStream.write(initMessage);
-  
+
     // Block until the stream has closed...
     await new Promise<void>((res) => {
       // The server has determined this stream must close
@@ -173,25 +184,23 @@ let INSTANCE: Faas = undefined;
 
 const getInstance = (): Faas => {
   INSTANCE = INSTANCE || new Faas();
-  return INSTANCE; 
-}
-
+  return INSTANCE;
+};
 
 /**
  * Register a HTTP handler
  */
-export const http = (handler: HttpMiddleware): Faas => 
-  getInstance().http(handler);
-
+export const http = (...handlers: HttpMiddleware[]): Faas =>
+  getInstance().http(...handlers);
 
 /**
  * Register an event handler
  */
-export const event = (handler: EventMiddleware): Faas => 
-  getInstance().event(handler);
+export const event = (...handlers: EventMiddleware[]): Faas =>
+  getInstance().event(...handlers);
 
 /**
  * Start the FaaS server with a universal handler
  */
-export const start = async (handler: TriggerMiddleware): Promise<void> => 
-  await getInstance().start(handler);
+export const start = async (...handlers: TriggerMiddleware[]): Promise<void> =>
+  await getInstance().start(...handlers);
diff --git a/tsconfig.json b/tsconfig.json
@@ -3,7 +3,7 @@
     "esModuleInterop": true,
     "declaration": true,
     "module": "commonjs",
-    "target": "ES5",
+    "target": "es6",
     "outDir": "lib",
     "allowJs": true,
     "types": ["node", "jest"],