@gpt-flow/express

A middleware for Express.js applications to capture, log, and send error reports and request data to the GPT-Flow API for analysis.

Installation

Install the package via npm:

npm install @gpt-flow/express

Basic Setup

Step 1: Environment Variables Setup

You need to provide your projectId, publicKey, and projectUrl for GPT-Flow to function properly. Add these variables to a .env file at the root of your project:

PROJECT_ID=your_project_id
PUBLIC_KEY=your_public_key
PROJECT_URL=https://gpt-flow-llm-api.onrender.com

Step 2: Configure GPT-Flow Programmatically

If you don’t want to use a .env file, you can configure GPT-Flow directly in your application code:

const gptFlow = require('@gpt-flow/express');

gptFlow.configure({
    projectId: 'your_project_id',       // Replace with your actual project ID
    publicKey: 'your_public_key',       // Replace with your actual public key
    projectUrl: 'https://gpt-flow-llm-api.onrender.com' // Your GPT-Flow URL
});

Step 3: Using the Middleware

1. Add the GPT-Flow middleware to your Express app:

   const express = require('express');
   const { errorHandlingMiddleware } = require('@gpt-flow/express');
   
   const app = express();
   
   // Use GPT-Flow middleware to handle errors
   app.use(errorHandlingMiddleware());
   
   // Example route
   app.get('/', (req, res) => {
       res.send('Hello, GPT-Flow!');
   });
   
   // Error route to simulate an error
   app.get('/error', (req, res) => {
       throw new Error('This is a simulated error.');
   });
   
   app.listen(3000, () => {
       console.log('Server running on http://localhost:3000');
   });

2. Customizing Error Responses: If you want to customize how errors are handled or how the user is notified, you can pass an options object when using errorHandlingMiddleware:

   app.use(errorHandlingMiddleware({
       customResponse: 'Something went wrong! Our team is looking into it.',
       renderErrorPage: false  // Set to true if you want to render a custom error page
   }));

Step 4: Additional Features (Optional)

Request Logging

To log every request made to the server:

const { requestLoggingMiddleware } = require('@gpt-flow/express');

// Use request logging middleware
app.use(requestLoggingMiddleware);

Request Validation (Using Joi)

To validate incoming request payloads, you can integrate Joi:

const Joi = require('joi');
const { requestValidationMiddleware } = require('@gpt-flow/express');

// Define a schema
const schema = Joi.object({
    name: Joi.string().min(3).required(),
});

// Use validation middleware
app.post('/data', requestValidationMiddleware(schema), (req, res) => {
    res.send('Data received successfully');
});

Handling Asynchronous Errors

For handling errors in async routes, use the asyncErrorHandler function:

const { asyncErrorHandler } = require('@gpt-flow/express');

// Example async route with error handling
app.get('/async-error', asyncErrorHandler(async (req, res, next) => {
    const result = await someAsyncOperation();  // Simulating async operation
    res.send(result);
}));

Step 5: Testing the Middleware

After setting everything up, you can test it by running your Express server:

node index.js

1. Go to http://localhost:3000/ in your browser or use a tool like Postman or curl to make requests.
2. To simulate an error, visit http://localhost:3000/error, and GPT-Flow should capture and log the error.