During our day to day activities we see many HTTP status code, so below is the List of common HTTP status code we see in SAP.
HTTP Response Status Codes
Every HTTP request that is received by a server is responded to with a 3-digit HTTP status code. They are grouped into five classes.
The class of a status code can be quickly identified by its first digit:
4xx: Client Error
5xx: Server Error
**Note: HTTP errors are often caused by incorrect URLs, interconnected proxy servers, or by slow processing in a system**
Request received, continuing process.
This class of status code indicates a provisional response, consisting only of the Status-Line and optional headers, and is terminated by an empty line. Since HTTP/1.0 did not define any 1xx status codes, servers must not send a 1xx response to an HTTP/1.0 client except under experimental conditions.
This class of status codes indicates the action requested by the client was received, understood, accepted and processed successfully.
The requested resource retrieval is successful, and a full payload of the requested resource is returned.
The request has been fulfilled and resulted in a new resource being created.
The request has been accepted for processing, but the processing has not been completed.
204 -No Content
The server successfully processed the request, but is not returning any content. Usually used as a response to a successful delete request.
This class of status code indicates the client must take additional action to complete the request. Many of these status codes are used in URL redirection.A user agent may carry out the additional action with no user interaction only if the method used in the second request is GET or HEAD. A user agent should not automatically redirect a request more than five times, since such re-directions usually indicate an infinite loop.
300 -Multiple Choices
Indicates multiple options for the resource that the client may follow.
301 -Moved Permanently
This and all future requests should be directed to the given URL.
Client Errors (4xx):
Client errors, or HTTP status codes from 400 to 499, are the result of HTTP requests sent by a HTTP client. Even though these types of errors are client-related, it is often useful to know which error code a user is encountering to determine if the potential issue can be fixed by server configuration.
400 -Bad Request
The 400 status code, or Bad Request error, means the HTTP request that was sent to the server has invalid syntax.
The 401 status code, or an Unauthorized error, means that the user trying to access the resource has not been authenticated or has not been authenticated correctly. This means that the user must provide credentials to be able to view the protected resource. An example scenario where a 401 Unauthorized error would be returned is if a user tries to access a resource that is protected by HTTP authentication if enters invalid username and password.
The 403 status code, or a Forbidden error, means that the user made a valid request but the server is refusing to serve the request, due to a lack of permission to access the requested resource.
404 -Not Found
The 404 status code, or a Not Found error, means that the user is able to communicate with the server but it is unable to locate the requested resource.
405 -Method Not Allowed
The method specified in the Request Line is not allowed for the resource identified by the Request URI.
407 -Proxy Authentication Required
The client must first authenticate itself with the proxy.
408 -Request Timeout
The server timed out waiting for the request. According to HTTP specifications: “The client did not produce a request within the time that the server was prepared to wait. The client MAY repeat the request without modifications at any later time.”
There is an internal access conflict to the specified resource.
Indicates that the resource requested is no longer available and will not be available again. This should be used when a resource has been intentionally removed and the resource should be purged.
429 -Too Many Requests
The user has sent too many requests in a given period of time. This error message is typically encountered if API rate limits, set to protect against DoS attacks and to preserve server responsiveness, have been exceeded..
Server Errors (5xx):
Server errors, or HTTP status codes from 500 to 599, are returned by server when it is aware that an error has occurred or is otherwise not able to process the request.
500 -Internal Server Error
The 500 status code, or Internal Server Error, means that server cannot process the request for an unknown reason.
501 -Not Implemented
The server does not support the functionality required to fulfill the request.
502 -Bad Gateway
The 502 status code, or Bad Gateway error, means that the server is a gateway or proxy server, and it is not receiving a valid response from the backend servers that should actually fulfill the request.
503 -Service Unavailable
The 503 status code, or Service Unavailable error, means that the server is overloaded or under maintenance. This error implies that the service should become available at some point.
504 -Gateway Timeout
The 504 status code, or Gateway Timeout error, means that the server is a gateway or proxy server, and it is not receiving a response from the backend servers within the allowed time period.
505 -HTTP Version Not Supported
The server does not support the HTTP protocol version used in the request.
507 -Insufficient Storage
The server is unable to store the representation needed to complete the request.
599 -Network connect timeout error (Unknown)
This status code is not specified in any RFCs, but is used by Microsoft HTTP proxies to signal a network connect timeout behind the proxy to a client in front of the proxy.
Hope this will help you guys.