First, ensure that you have properly installed `next-connect` and it's correctly imported into your file where you're using it.
Install `next-connect` via npm or yarn if you haven't already:
```bash
npm install next-connect
# or
yarn add next-connect
```
Now, let's look at an example of how you could set up an API route with `next-connect` in a Next.js project that uses `multer` for file uploads and `Prisma` for database interaction.
```typescript
// pages/api/upload.js
import nextConnect from 'next-connect';
import multer from 'multer';
import { PrismaClient } from '@prisma/client';
const prisma = new PrismaClient();
// set up storage using multer
const storage = multer.memoryStorage();
const upload = multer({ storage: storage });
const apiRoute = nextConnect({
onError(error, req, res, next) {
console.error(error);
res.status(501).json({ error: `Sorry, something Happened! ${error.message}` });
},
onNoMatch(req, res) {
res.status(405).json({ error: `Method '${req.method}' Not Allowed` });
},
});
// You might want to declare the following type if you are using TypeScript
// and you have extended the NextApiRequest with additional properties, like file
import type { NextApiRequest, NextApiResponse } from 'next';
interface RequestWithFile extends NextApiRequest {
file: Express.Multer.File;
}
apiRoute.use(upload.single('file'));
apiRoute.post(async (req: RequestWithFile, res: NextApiResponse) => {
if (!req.file) {
return res.status(400).json({ error: 'No file uploaded' });
}
// Do something with the uploaded file
// For example, you might want to store the file in a cloud storage service
// Update the user avatar URL after the file is uploaded
// Assuming you have a user id from the request body or URL
const userId = req.body.userId;
const avatarUrl = 'path_to_the_uploaded_file'; // Replace this with your own logic
await prisma.user.update({
where: { id: userId },
data: { avatarUrl: avatarUrl },
});
res.status(200).json({ message: 'File uploaded successfully', avatarUrl: avatarUrl });
});
export default apiRoute;
// Since you're dealing with multipart/form-data, you need to disable the body parser for this route
export const config = {
api: {
bodyParser: false,
},
};
```
This example uses `next-connect` for the route handling and `multer` for file uploads. If you are using TypeScript, make sure that the types are properly defined so that TypeScript is aware of the additional `file` property on the `req` object. If you extend `NextApiRequest` with additional properties, make sure that you have correctly included such definitions in your type interfaces.
If you are still facing the "nextConnect is not callable" issue, there might be a few problems:
1. Check if `next-connect` is properly installed.
2. Ensure that you are correctly importing `next-connect` as demonstrated above.
3. If you are using a default export, make sure that there are no conflicting named exports of the same name.
4. Check if there's a version mismatch of the `next-connect` package that might be causing compatibility issues with your TypeScript version or other typings in your project.
Remember that the error message you might be receiving could also depend on the context of how you're using `next-connect` in your application. Therefore, you'll also need to check if the usage adheres to the documentation of `next-connect` and if there are other parts of your code that could be causing conflicts with `next-connect`.