Abstract
2XX
201
Created
Requested resource is created successfully
204
No Content
Server successfully processed the HTTP Request , but isn’t returning any content
218
This is Fine
Specifically for Apache servers that serve as a Reverse Proxy (反向代理) with ProxyErrorOverride on
For example, The Server behind Apache can send the 218 status code, so the Client will receive 218 even when there is an error code like 404
3XX
301
Permanent Redirect
Telling the Client (usually a web browser or a web crawler) that the requested resource has moved permanently to a new location
One use case is when clients accessing via HTTP , but server only wants to serve via HTTPS
302
Temporary Redirect
The redirected page isn’t going to be indexed by search engine. The page that performs the redirects is
If you need to permanently move a page to a new location, we should use 301
Use cases are Temporary Maintenance and A/B Testing
4XX
Indicates the Client -side has some issues
400
Bad Request
The HTTP Request cannot be fulfilled due to bad syntax.
401
Unauthorised
You need to provide valid credentials (e.g., login information) to access this resource, and the ones you provided are not accepted
403
Forbidden
Happens when the provided Authentication information is rejected
404
Unfound
Resources can’t be found on Server
409
Conflict
Returned when the same resource is being processed
Same user is created
Concurrency Conflicts
418
I’m a teapot
Indicates that the Server refuses to brew coffee because it is, permanently, a teapot
420
Enhance Your Calm
Can be used to tell Client it is being rated limited for making too many requests
Replaced by 429
429
Too Many Requests
Returned when a request can’t be served due to rate limiting
451
Unavailable for legal reasons
Reference to Fahrenheit 451
The user agent requested a resource that cannot legally be provided, such as a web page censored by a government. Or like Netflix geo-lock
Usually can be solved with a VPN
5XX
Indicates the Server -side has some issues
500
Internal Server Error
Some errors on the Server
502
504
Gateway Timeout
Indicates that a Proxy , didn’t receive a timely response from an upstream server it needed to access in order to complete the request
530
Site Fronzen
Can be used when the site owner’s free trial ends, the platform freezes the public access
References
HTTP Status Codes that should never have been created
VIDEO