HTTP protocol----Request method and Status code

Now widely used is the http/1.1 version, released in 1997.

Understanding the HTTP protocol begins with the request, such as:

Post/form/entry http/1.1

format : request method URI Protocol version

Request Method :

get: Gets the resource specified by the URI, the main purpose is to obtain

POST: Transfers the principal to a URI, the primary purpose of which is to transmit , not to get

PUT: Transfers A file , contains the contents of the file in the request body, and then saves to the location specified by the URI.

head: Gets the head of the get result only, removing the body.

Delete: remove file , is put inverse operation

Options: Query The method that specifies the resource support for the request URI. Usage such as:

OPTIONS * http/1.1

Host:xxx

Note : Because the put and delete methods involve direct manipulation of server files , the general web site is not supported.

Unless a web authentication mechanism is used with the.

Common Status Codes :

1XX: Indicates a message

2XX: Success

The OK request succeeds, and the content is returned

204 No content: Requests are processed successfully, but nothing is returned

206:partial content: The server sends back a range of contents as requested by the client.

3XX: redirect

301:moved permanently: The requested resource has been permanently assigned a new URI, this time with the new URI access

302:found: The requested resource has been temporarily assigned a new URI, this time with a new URI access

As you can see, either 301 or 302, the requested resource has two URIs

303:see Other: Similar to 302, request resource has a new URI, get to obtain

304:not Modified: The resource was found but did not meet the conditions contained in the request message (not related to redirection)

4XX: Client Error

400:bad Request: There is a syntax error in the requested message

401:unauthorized: No authentication information is included in the sent request, or authentication failed

403:forbidden: Access denied (such as permissions and other issues)

404:not Found: No URI specified resource on the server

5XX: Server Error

500:internal Server error: Server side errors occurred while executing the request

503:service Unavailable: The server is unable to process the request (server is overloaded or maintenance, etc.)

HTTP protocol----Request method and Status code