Summary of HTTP return codes

The meaning of the HTTP protocol status code is mainly divided into five categories, generally:
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1xx Retention
2XX indicates that the request was successfully received
3xx requesting customers to further refine requests for completion
4XX Customer Error
5XX Server Error

MB Continue
indicates that the client should continue to request. Loopback is used to inform the client that this request has been received and has not been rejected by the server.
The client should continue to send the remaining request data or the request has been completed, or the loopback data should be ignored. Server must send
The final loopback is after the request.

protocols switching
The server changes the application protocol of the current connection by upgrade header information according to customer service request. Server will change protocol immediately based on upgrade header
At the end of the 101 return with a blank line.

successful
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OK
Indicates that the customer service request has been successfully received, resolved and accepted.

201 Created
The request has been completed and a new return resource has been created. The resource created may be a URI resource, usually specified by the URI resource in the location header. Loopback should contain an Entity data
It also contains resource characteristics and location Select the appropriate method through the user or user agent. The Entity Data format is specified by coal type, i.e. Content-type head. The Start server
You must create the specified resource before returning the 201 status code. If the behavior is not executed immediately, the server should return 202.

accepted
The request has been accepted for processing. But the process has not been completed. The request may or might not have been complied with because the process may have been rejected during actual execution.

203 non-authoritative Information

204 No Content
The server has accepted the request and it is not necessary to return the entity data and may need to return the update information. The loopback may contain new or updated information rendered by entity-headers.

205 Reset Content
The server has accepted the request and the user agent should reset the document view.

206 Partial Content
The server has accepted the part of the request for a GET request resource. The request must contain a range header information to indicate that the fetch scope may have to contain If-range header information to establish the request condition.

redirection
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Multiple choices
The request resource conforms to any one rendering.

permanently moved
The requested resource has been assigned a new URI.

302 Found
A temporary file that requests a resource through a different URI.
303 and other

304 Not Modified
If the client has completed a conditional request and the request is allowed, but the document has not changed, the server should return a 304 status code. 304
The status code must not contain the information body, which usually ends with the first empty line after a header field.

305 Use Proxy
the requested resource must be accessed through the proxy (specified by the Location field). The location resource gives the URI of the proxy.

306 Unused

307 Temporary Redirect

Client Error
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Bad Request
The server is unable to understand the request information because of incorrect syntax.

401 Unauthorized
If the request requires user authentication. The loopback should contain a Www-authenticate header field that indicates the permission to request a resource.

402 Payment Required
Preserve status Code

403 Forbidden
The server accepted the request, but was refused to process it.

404 Not Found
The server has found any resources that match the Request-uri.

405 Menthod not allowed
The Request-line requested method is not allowed through the specified URI.

406 Not acceptable

407 Proxy Authentication Required

408 reqeust Timeout
The customer service side did not submit any requests during the server wait processing time.

409 Conflict

410 Gone

411 Length Required
The server refused to accept the request without defining the Content-length field.

412 Precondition Failed

413 Request Entity Too Large
The server refused to process the request because the request data exceeded the scope the server was able to handle. The server may close the current connection to prevent the client from continuing the request.

414 Request-uri Too Long
Server denial of service current request because the length of the URI exceeds the resolution scope of the server.

415 Unsupported Media Type
Server denial of service current request because the request data format is not supported by the requested resource.

416 Request Range not satisfialbe

417 Expectation Failed

Server Error
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Internal Server Error
The server encountered an exception that prevented the execution of the current request

501 Not implemented
The server does not have the appropriate execution action to complete the current request.

502 Bad Gateway

503 Service Unavailable
The server cannot process the current request because of a temporary file overload.

504 Gateway Timeout

505 Http Version not supported