Express app.METHOD() Method

Posted in Express Tutorial

Updated on Feb 17, 2024

By Mari Selvan

👁️ 35 - Views

⏳ 4 mins

💬 1 Comment

Photo Credit to CodeToFun

🙋 Introduction

Express.js, a popular Node.js web application framework, provides a flexible way to handle various HTTP methods using the app.METHOD() method.

This guide will explore how you can leverage app.METHOD() to handle custom HTTP methods beyond the standard ones like GET, POST, PUT, and DELETE.

💡 Syntax

The app.METHOD() method follows a dynamic syntax where METHOD is the HTTP method you want to handle. It can be any valid HTTP method, including standard ones like GET, POST, PUT, DELETE, as well as custom ones like SEARCH, PATCH, etc.

syntax.js

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app.METHOD(path, callback)

path: A string representing the route or path for which the custom HTTP method is being handled.
callback: The route handler function that processes requests with the specified custom HTTP method.

❓ How app.METHOD() Works

With app.METHOD(), you can define route-specific logic to handle custom HTTP methods. This allows you to extend the capabilities of your API or web application beyond the standard set of HTTP methods.

example.js

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app.search('/products', (req, res) => {
  // Custom logic for handling SEARCH requests on the '/products' route
  res.send('Performing product search');
});

In this example, the custom HTTP method SEARCH is handled for the /products route.

📚 Use Cases

Custom Actions:

Use app.METHOD() to define custom actions that go beyond the standard CRUD operations.

example.js

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app.vote('/posts/:postId', (req, res) => {
  const postId = req.params.postId;
  // Custom logic for handling VOTE requests on a specific post
  res.send(`Voted on post with ID ${postId}`);
});

Integration with External Systems:

Leverage app.METHOD() for routes that integrate with external systems using custom HTTP methods.
example.js
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```
app.notify('/external', (req, res) => {
  // Custom logic to notify an external system
  res.send('Notification sent to external system');
});
```

🏆 Best Practices

Clear Documentation:

Document custom HTTP methods thoroughly in your API documentation to guide developers on their usage and purpose.
example.js
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```
**Custom Method: VOTE**

- **Endpoint:** `/vote/:id`
- **Description:** Vote on a specific item.
- **HTTP Method:** `VOTE`
```
Consistent Naming:

Maintain a consistent naming convention for custom HTTP methods to enhance code readability and maintainability.
example.js
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```
app.customAction('/route', (req, res) => {
  // Custom logic for handling CUSTOM_ACTION requests
  res.send('Handling custom action');
});
```

Middleware Integration:

Integrate middleware functions with app.METHOD() for tasks like authentication or authorization before processing requests with custom HTTP methods.

example.js

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const authenticateUser = (req, res, next) => {
  // Implement your authentication logic here
  if (req.isAuthenticated()) {
    return next();
  } else {
    res.status(401).send('Unauthorized');
  }
};

app.customAction('/protected', authenticateUser, (req, res) => {
  // Custom logic for handling CUSTOM_ACTION on a protected route
  res.send('Handling custom action on a protected route');
});

🎉 Conclusion

The app.METHOD() method in Express.js provides a powerful mechanism to handle custom HTTP methods, allowing you to extend the functionality of your web applications. By understanding its syntax, use cases, and best practices, you can efficiently integrate custom actions and interactions into your Express.js projects.

Now, armed with knowledge about app.METHOD(), explore new possibilities and enhance the capabilities of your Express.js applications!