Express res.status() Method

Posted in Express Tutorial

Updated on Feb 18, 2024

By Mari Selvan

👁️ 29 - Views

⏳ 4 mins

💬 1 Comment

Photo Credit to CodeToFun

🙋 Introduction

In Express.js, controlling the HTTP response status code is crucial for conveying the outcome of a request to the client. The res.status() method is a powerful tool that allows developers to explicitly set the HTTP status code for a response.

This guide will walk you through the syntax, use cases, and best practices of the res.status() method in Express.js.

💡 Syntax

The syntax for the res.status() method is straightforward:

syntax.js

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res.status(statusCode)

statusCode: The HTTP status code to be set for the response.

🚧 Setting Custom Status Codes

With res.status(), you can easily customize the HTTP status code returned to the client. This is particularly useful when you want to provide more context about the outcome of a request.

example.js

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app.get('/error', (req, res) => {
  // Simulate an error scenario
  const error = new Error('Internal Server Error');
  res.status(500).send({ error: error.message });
});

In this example, the route /error sets a custom status code of 500 (Internal Server Error) to indicate an error condition.

📚 Use Cases

Handling Errors:

Use res.status() to dynamically set the appropriate status code based on the outcome of the request, such as data availability or errors.

example.js

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app.get('/api/data', (req, res) => {
  // Check if the required data is available
  if (dataIsNotAvailable()) {
    res.status(404).send('Data Not Found');
  } else {
    res.status(200).send('Data Found');
  }
});

Redirecting Users:

Set a 301 status code (Moved Permanently) to inform clients that a resource has permanently moved to a new location.
example.js
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```
app.get('/old-route', (req, res) => {
  // Redirect users to a new route
  res.status(301).redirect('/new-route');
});
```

🏆 Best Practices

Use Descriptive Status Codes:

Choose status codes that accurately represent the nature of the response. This helps clients understand the outcome without relying solely on the response body.

example.js

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app.post('/create', (req, res) => {
  if (creationSuccessful()) {
    res.status(201).send('Resource Created Successfully');
  } else {
    res.status(400).send('Bad Request - Unable to Create Resource');
  }
});

Centralize Status Code Logic:

Avoid duplicating status code logic across multiple routes. Centralize the logic in utility functions or middleware to maintain consistency.

example.js

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// Centralized status code utility function
const sendResponseWithCode = (res, statusCode, message) => {
  res.status(statusCode).send(message);
};

// Using the utility function in a route
app.get('/status', (req, res) => {
  sendResponseWithCode(res, 418, 'I am a teapot');
});

Utilize Redirects Appropriately:

When redirecting, use status codes like 301 (Moved Permanently) for permanent moves and 302 (Found) or 307 (Temporary Redirect) for temporary redirects.
example.js
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```
app.get('/old-url', (req, res) => {
  // Redirect users to a new URL temporarily
  res.status(307).redirect('/temporary-url');
});
```

🎉 Conclusion

The res.status() method in Express.js provides developers with fine-grained control over the HTTP status codes returned to clients. By leveraging this method, you can enhance the clarity and context of your responses, leading to a more effective and understandable communication between your server and clients.

Now, armed with knowledge about the res.status() method, go ahead and tailor your Express.js applications to deliver precise and informative HTTP status codes!