Overview of HTTP Status Codes for Software Testers
HTTP status codes are three-digit numbers that define the present status of a client's request to a server. These codes are returned by the server as a response to a client's HTTP request. HTTP status codes indicate whether the request was successful, failed, or redirected to another resource.
A request is made to the server (where the website is being hosted) each time a Uniform Resource Locator (URL) is entered into the client browser. In other words, the client sends a Hypertext Transfer Protocol (HTTP) request to the server, and the server replies by returning an HTTP status code to the client, indicating whether the request was successful or not. The server answers when you submit the request via the HTTP protocol.
How HTTP Codes are useful in Software Testing
Testing professionals can find problems and faults that can arise during client-server communication by looking at the HTTP status codes that the server returns. These codes can aid testers in locating the issue's origin, whether it stems from a client-side or server-side problem, and in taking the necessary remedial measures. Additionally, testers can check the system's functionality and make sure the desired behaviour is being followed by using HTTP status codes.
A request is sent to the web server every time when a user enters in a URL in the browser, which the latter subsequently processes and returns with a response. This answer is frequently delivered as a collection of HTML, CSS, PDF, or JSON documents together with an HTTP header. The HTTP header includes the status codes in addition to details about the client, server, and requested page. Again, the user is not required to read these codes, but they do display when anything goes wrong. These codes are returned each time a server gets a request from a client.
Types of HTTP Status Codes
Every status code falls into one of five separate groups, which are identified by the first digit of each number. For instance, the status code 404 falls within group 4xx. The classification of groups is described below:
Informational (101 – 199): This type of requests is informative and denotes that the server initiated the client's request.
Successful Responses (201 – 299): A success message is shown when a request that the server received from the client has been successfully processed or completed.
Redirects (301 – 399): There are scenarios where a user's requested web page or information may have been relocated to another page or link, in which case a redirection occurs. This indicates that the request was received by the server, but more steps are required to allow it to be completed.
Client Errors (401 – 499): This group is referred to as client error codes. The server has received the request; however it cannot be processed because it could have incorrect syntax.
Server Errors (501 – 599): This group is referred to as server error codes. This status code comes when the request is valid but contains an error, making it impossible for the server to process it.