feat(api): allow CORS all origins and handle empty message param

README.md

@@ -177,17 +177,26 @@ To start a conversation with ChatGPT, send a POST request to the server's `/conv
 ```
 The server will return a JSON object containing ChatGPT's response:
 ```JSON
+// HTTP/1.1 200 OK
 {
     "response": "I'm doing well, thank you! How are you?",
     "conversationId": "your-conversation-id",
     "messageId": "response-message-id"
 }
 ```
 
-If the request is unsuccessful, the server will return a JSON object with an error message and a status code of 503.
+If the request is unsuccessful, the server will return a JSON object with an error message.
 
+If the request object is missing a required property (e.g. `message`):
+```JSON
+// HTTP/1.1 400 Bad Request
+{
+    "error": "The message parameter is required."
+}
+```
 If there was an error sending the message to ChatGPT:
 ```JSON
+// HTTP/1.1 503 Service Unavailable
 {
     "error": "There was an error communicating with ChatGPT."
 }

bin/server.js

@@ -1,5 +1,6 @@
 #!/usr/bin/env node
 import fastify from 'fastify';
+import cors from '@fastify/cors';
 import { FastifySSEPlugin } from "fastify-sse-v2";
 import fs from 'fs';
 import { pathToFileURL } from 'url'
@@ -45,7 +46,10 @@ const chatGptClient = new ChatGPTClient(settings.openaiApiKey, settings.chatGptC
 
 const server = fastify();
 
-server.register(FastifySSEPlugin);
+await server.register(FastifySSEPlugin);
+await server.register(cors, {
+    origin: '*',
+});
 
 server.post('/conversation', async (request, reply) => {
     const body = request.body || {};
@@ -67,6 +71,15 @@ server.post('/conversation', async (request, reply) => {
     let result;
     let error;
     try {
+        if (!body.message) {
+            const invalidError = new Error();
+            invalidError.data = {
+                code: 400,
+                message: 'The message parameter is required.',
+            };
+            // noinspection ExceptionCaughtLocallyJS
+            throw invalidError;
+        }
         const parentMessageId = body.parentMessageId ? body.parentMessageId.toString() : undefined;
         result = await chatGptClient.sendMessage(body.message, {
             conversationId,
@@ -87,18 +100,24 @@ server.post('/conversation', async (request, reply) => {
             console.debug(result);
         }
     } else {
-        console.error(error);
+        const code = error?.data?.code || 503;
+        if (code === 503) {
+            console.error(error);
+        } else if (settings.apiOptions?.debug) {
+            console.debug(error);
+        }
+        const message = error?.data?.message || 'There was an error communicating with ChatGPT.';
         if (body.stream === true) {
             reply.sse({
                 id: '',
                 event: 'error',
                 data: JSON.stringify({
-                    code: 503,
-                    error: 'There was an error communicating with ChatGPT.',
+                    code,
+                    error: message,
                 }),
             });
         } else {
-            reply.code(503).send({ error: 'There was an error communicating with ChatGPT.' });
+            reply.code(code).send({ error: message });
         }
     }
 });

package.json

@@ -32,6 +32,7 @@
     "api-wrapper"
   ],
   "dependencies": {
+    "@fastify/cors": "^8.2.0",
     "@fortaine/fetch-event-source": "^3.0.6",
     "boxen": "^7.0.1",
     "clipboardy": "^3.0.0",