Golang get and POST request sending and parsing for Web programming

This is a creation in Article, where the information may have evolved or changed.

This article is an introductory article that introduces the techniques used by Golang Web programming through a simple example.

The structure of the article includes:

1. Client-get Request
2. Client-post Request
3. Server processes Get and Post data

In the encapsulation of data, we use JSON in part, so this article also involves the encoding and decoding of JSON in Golang.

First, Client-get

 PackageMainimport (  "FMT"  "Net/url"  "Net/http"  "Io/ioutil"  "Log") Func Main () {  U_: = URL. Parse ("Http://localhost:9001/xiaoyue")  Q: = U.query ()  Q. Set ("username","User")  Q. Set ("Password","passwd")  U.rawquery =Q. Encode ()  Res, ERR: = http. Get (U.string ());  ifErr! = Nil {        Log. Fatal (ERR)return   }  result, err: = Ioutil. ReadAll (Res. Body)  Res. Body.close ()  ifErr! = Nil {        Log. Fatal (ERR)return   }  Fmt. Printf ('%s', result)}

Second, Client-post

Package Mainimport (  "FMT"  "Net/url"  "Net/http"  "Io/ioutil"  "Log"  "bytes"  "Encoding/json") Type Serverstruct{  ServerNamestring  ServerIPstring}type Serverslicestruct{  Servers []server  Serversidstring}func Main () {  varS Serverslice  varNewServer Server;  Newserver.servername ="Guangzhou_vpn";  Newserver.serverip ="127.0.0.1"         S.servers = Append (S.servers, NewServer)  S.servers = Append (S.servers, Server{servername:"Shanghai_vpn", ServerIP:"127.0.0.2"})  S.servers = Append (S.servers, Server{servername:"Beijing_vpn", ServerIP:"127.0.0.3"})    S.serversid ="team1"  B, err: = json. Marshal (s)  ifErr! = Nil {    Fmt. Println ("JSON err:", err)  }  Body: = bytes. Newbuffer ([]byte(b))  Res,err: = http. Post ("Http://localhost:9001/xiaoyue","Application/json;charset=utf-8", body)  ifErr! = Nil {    Log. Fatal (ERR)    return  }  result, err: = Ioutil. ReadAll (Res. Body)  Res. Body.close ()  ifErr! = Nil {    Log. Fatal (ERR)    return  }  Fmt. Printf ('%s ', result)}

Package Mainimport (  "FMT"  "Net/http"  "Strings"  "HTML"  "Io/ioutil"  "Encoding/json") Type Serverstruct{  ServerNamestring  ServerIPstring}type Serverslicestruct{  Servers []server  Serversidstring}func Main () {  http. Handlefunc ("/", handler)  http. Listenandserve (": 9001", nil)}func Handler (w http. Responsewriter, R *http. Request) {  R.parseform ()//parse parameter, default is not resolved  Fmt. fprintf (W,"Hi, I Love you%s"Html. Escapestring (R.url. path[1:]))  ifR.method = ="GET"{    Fmt. Println ("Method:", R.method)//How to get the request    Fmt. Println ("username", r.form["username"])    Fmt. Println ("Password", r.form["Password"])     forK, V: = Range R.form {      Fmt. Print ("key:"K"; ")      Fmt. Println ("val:", strings. Join (V,""))    }  }Else ifR.method = ="POST"{    result, _:= Ioutil. ReadAll (R.body)    R.body.close ()    Fmt. Printf ("%s\n", result)    //unknown types of recommended processing methods    varFInterface{}    Json. Unmarshal (result, &f)    M: = f. (map[string]Interface{})     forK, V: = range m {      SwitchVV: = V. (type) {         Case string:          Fmt. Println (k,"is string", VV)         Case int:          Fmt. Println (k,"is int", VV)         CaseFloat64:          Fmt. Println (k,"is Float64", VV)         Case[]Interface{}:          Fmt. Println (k,"is an array:")           forI, U: = Range VV {            Fmt. Println (i, u)          }        default:          Fmt. Println (k,"is of a type I don ' t know what to handle")      }    }     //structure known, parse to struct     vars serverslice;    Json. Unmarshal ([]byte(result), &s)    Fmt. Println (S.SERVERSID);      fori:=0; I<len (s.servers); i++ {      Fmt. Println (S.servers[i]. ServerName)      Fmt. Println (S.servers[i]. ServerIP)    }  } }