Error: The pattern `api/email.js` defined in functions doesn’t match any Serverless Functions inside the `api` directory (Vercel/Remix-run)

If you’re reading this, chances are you’ve stumbled upon the frustrating error “The pattern `api/email.js` defined in functions doesn’t match any Serverless Functions inside the `api` directory” while trying to deploy your Remix-run application on Vercel. Fear not, dear developer, for we’re about to embark on a journey to debug and resolve this pesky issue once and for all!

What’s causing the error?

Before we dive into the fix, let’s understand what’s causing this error. The error message indicates that Vercel is unable to find a matching Serverless Function inside the `api` directory that corresponds to the pattern `api/email.js` defined in your `functions` configuration.

This usually occurs when there’s a mismatch between the function pattern defined in your `functions` configuration and the actual file structure of your Serverless Functions inside the `api` directory.

Step 1: Review your `functions` configuration

Open your `vercel.json` or `remix.config.js` file and review your `functions` configuration. Look for the following code:

"functions": [
  {
    "pattern": "api/email.js",
    " runtime": "@vercel/node"
  }
]

In this example, the `pattern` property is set to `api/email.js`, indicating that Vercel should look for a Serverless Function named `email.js` inside the `api` directory.

Step 2: Check your `api` directory structure

Next, let’s inspect the file structure of your `api` directory. Verify that you have a file named `email.js` inside the `api` directory. If you don’t, create one or update the `pattern` property to match the actual file name.

Here’s an example of what your `api` directory structure might look like:

api
email.js
users.js
products.js

In this example, we have three Serverless Functions: `email.js`, `users.js`, and `products.js`. Make sure the file name matches the `pattern` property in your `functions` configuration.

Step 3: Update your `functions` configuration (if necessary)

If you’ve reviewed your `functions` configuration and `api` directory structure, and you’re still encountering the error, it’s possible that you need to update your `functions` configuration to match the actual file structure.

For example, if you have multiple Serverless Functions inside the `api` directory, you might need to update your `functions` configuration to include a glob pattern like this:

"functions": [
  {
    "pattern": "api/*.js",
    "runtime": "@vercel/node"
  }
]

This will instruct Vercel to look for any `.js` files inside the `api` directory and deploy them as Serverless Functions.

Step 4: Verify your Serverless Function export

Another common issue that might cause this error is an incorrect export in your Serverless Function file.

Open your `email.js` file (or the file corresponding to the `pattern` property) and verify that you’re exporting a valid Serverless Function. Here’s an example:

export async function handler(req, res) {
  // Your code here
}

Make sure you’re exporting a named function (in this case, `handler`) that takes `req` and `res` parameters.

Step 5: Redeploy your application

After making any changes to your `functions` configuration or Serverless Function files, redeploy your Remix-run application on Vercel.

If you’re using Vercel CLI, run the following command:

vercel deploy --prod

If you’re using the Vercel dashboard, click the “Deploy” button to redeploy your application.

Here are some common errors and troubleshooting tips to keep in mind:

Error	Troubleshooting Tip
Error: The pattern `api/email.js` is not a valid Serverless Function	Verify that your Serverless Function file is correctly exported and has a valid function signature (e.g., `export async function handler(req, res) { … }`)
Error: The pattern `api/email.js` is not found in the `api` directory	Check that your Serverless Function file exists in the correct location and that the file name matches the `pattern` property in your `functions` configuration
Error: Multiple Serverless Functions match the pattern `api/*.js`	Verify that your `functions` configuration is correctly setup to handle multiple Serverless Functions. You might need to update your `pattern` property to be more specific or use a glob pattern like `api/**/*.js`

Conclusion

There you have it, folks! By following these steps and troubleshooting tips, you should be able to resolve the pesky “The pattern `api/email.js` defined in functions doesn’t match any Serverless Functions inside the `api` directory” error and deploy your Remix-run application on Vercel successfully.

Remember to double-check your `functions` configuration, `api` directory structure, and Serverless Function exports to ensure that everything is correctly set up. If you’re still encountering issues, feel free to reach out to the Vercel or Remix-run communities for further assistance.

Happy deploying!

Frequently Asked Question

Got stuck with the error “The pattern `api/email.js` defined in functions doesn’t match any Serverless Functions inside the `api` directory” while using Vercel/Remix-run? Don’t worry, we’ve got you covered!