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Rabeeh Ebrahim
Rabeeh Ebrahim

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Demystifying HTTP Status Codes: Essential Knowledge for Node.js Newbies

Status codes are an essential part of web development, including Node.js, as they provide communication between the client (usually a web browser) and the server. They indicate the outcome of an HTTP request, helping developers and users understand what happened during a request-response cycle.

Here's a brief overview of why status codes are important:

  1. Communication: Status codes allow the server to communicate the outcome of a request to the client, indicating whether the request was successful, encountered an error, or requires further action.

  2. Debugging: They assist developers in diagnosing and debugging issues with web applications by providing clues about the nature of the problem.

  3. User Experience: For end-users, status codes help in understanding why an operation failed (e.g., a broken link or access denied), leading to a better user experience.

HTTP status codes are categorized into five series:

  • 1xx (Informational): This series provides interim responses to inform the client that the server is still processing the request. These are rarely used in practice.

  • 2xx (Successful): These status codes indicate that the client's request was received, understood, and successfully processed.

  • 3xx (Redirection): These codes indicate that further action is needed to fulfill the request. They often involve redirecting the client to a different URL or resource.

  • 4xx (Client Errors): These status codes signify that the client has made an error in the request, such as requesting a non-existent resource or lacking proper authentication.

  • 5xx (Server Errors): These codes indicate that the server encountered an error or is incapable of performing the request due to various reasons.

Common HTTP Status Codes for Node.js Developers:

  1. 200 OK: The most common success code, indicating a successful request and response.

  2. 201 Created: Used when a new resource has been successfully created as a result of the request.

  3. 204 No Content: Indicates that the request was successful, but there is no response body to return.

  4. 301 Moved Permanently: Signals a permanent redirection to a different URL.

  5. 400 Bad Request: Indicates that the client's request is malformed or contains invalid data.

  6. 401 Unauthorized: The client must provide valid credentials (e.g., a username and password) to access the requested resource.

  7. 403 Forbidden: The client does not have permission to access the requested resource, even if authenticated.

  8. 404 Not Found: The requested resource could not be found on the server.

  9. 500 Internal Server Error: A generic server error response when no more specific message is suitable.

  10. 503 Service Unavailable: Indicates that the server is temporarily unable to handle the request, typically due to overloading or maintenance.

Top comments (2)

thevnilva profile image
Tori Hevnilva

The Wikipedia page on HTTP status codes is a great bookmark:

codewithrabeeh profile image
Rabeeh Ebrahim

Thanks @norinit for adding.