An analysis of HTTP protocol GET request and POST request

I. INTRODUCTION of HTTP

1, HTTP protocol: (Hypertext Transport Protocol), that is, Hypertext Transfer Protocol. This protocol details the rules for communication between the browser and the World Wide Web server (message format).

　2. Message: the content that is transmitted when the client communicates with the server is what we call a message. the client is sent to the server called the " Request Message ", the server is sent to the client called " Response message."

3. Classification:

Request message:

GET request

POST request

Response message:

4. Message Format:

　　　　　　Message header: Includes Wenshou and message header

Second, GET request message

GET request message only: message header

First line of message

GET/BOOKSTORE01/B.HTML?USERNAME=DFADF&PWD=DFA http/1.1 //Request way request path? parameter Key value pair &
　　　　　　
Message Header "Key-value pair format"

host:localhost:8080//Request destination IP address and port number
　　　　　　　　user-agent:mozilla/5.0 (Windows NT 6.1; WOW64; rv:27.0) gecko/20100101firefox/27.0//Current browser

accept:text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
//browser tells the server what format of file the browser can receive　　　　　　　　

accept-language:zh-cn,zh;q=0.8,en-us;q=0.5,en;q=0.3
//You can tell which location you are in　　　　　　　　
zh-cn: Simplified Chinese
en-US: American English

Accept-encoding:gzip, deflate
//browser tells the server that the browser can identify the decompression method　　　　　　　　

referer:http://localhost:8080/bookstore01/index.html
//Referer: Refers to the page from which the current page is to jump over

connection:keep-alive
//keep-alive: Indicates that the browser tells the server that this is a long connection　　　　　　　　

Get requests do not have blank lines and message bodies, get requests are passed through the address bar parameters!

Third, POST request message

　　　　Request First Line

post/bookstore01/b.html http/1.1        //request Path Request Protocol/version number  

//request Header

host:localhost:8080
User-ag ent:mozilla/5.0 (Windows NT 6.1; WOW64; rv:27.0) gecko/20100101 firefox/27.0
accept:text/html,application/xhtml+ xml,application/xml;q=0.9,*/*;q=0.8
accept-language:zh-cn,zh;q=0.8, en-us;q=0.5,en;q=0.3
Accept-encoding:gzip, deflate
referer:http://localhost:8080/bookstore01/index.html
connection:keep-alive

　　　　　　　　Blank Line

Username=zhangsan //message body

The POST request has a blank line and a request body, and the POST request passes the request parameters through the request body!

Iv. Response Messages

　　　　　Response First line:

http/1.1 OK // Protocol Name/version number response status Code status descriptor

server:apache-coyote/1.1
Accept-ranges:bytes
etag:w/"262-1510560961503"
Last-modified:mon, 08:16:01 GMT
　　　　　　　GMT
Content-type:text/html
content-length:262
Date:mon, 08:44:55 GMT

An analysis of HTTP protocol GET request and POST request