==>
GET /hello HTTP/1.1
Host: 127.0.0.1:12345
<==
HTTP/1.1 401 Unauthorized
WWW-Authenticate: Basic realm="Dotcoo User Login"
==>
GET /hello HTTP/1.1
Host: 127.0.0.1:12345
Authorization: Basic YWRtaW46YWRtaW5wd2Q=
<==
HTTP/1.1 200 OK
Content-Type: text/plain; charset=utf-8

package main
import ("fmt""io""net/http""log""encoding/base64""strings"
)
// hello world, the web server
func HelloServer(w http.ResponseWriter, req *http.Request) {auth := req.Header.Get("Authorization")if auth == "" {w.Header().Set("WWW-Authenticate", `Basic realm="Dotcoo User Login"`)w.WriteHeader(http.StatusUnauthorized)return}fmt.Println(auth)auths := strings.SplitN(auth, " ", 2)if len(auths) != 2 {fmt.Println("error")return}authMethod := auths[0]authB64 := auths[1]switch authMethod {case "Basic":authstr, err := base64.StdEncoding.DecodeString(authB64)if err != nil {fmt.Println(err)io.WriteString(w, "Unauthorized!\n")return}fmt.Println(string(authstr))userPwd := strings.SplitN(string(authstr), ":", 2)if len(userPwd) != 2 {fmt.Println("error")return}username := userPwd[0]password := userPwd[1]fmt.Println("Username:", username)fmt.Println("Password:", password)fmt.Println()default:fmt.Println("error")return}io.WriteString(w, "hello, world!\n")
}
func main() {http.HandleFunc("/hello", HelloServer)err := http.ListenAndServe(":8000", nil)if err != nil {log.Fatal("ListenAndServe: ", err)}
}

package evernoteimport ("bytes""errors""fmt""io/ioutil""net/http""net/http/cookiejar""net/url""regexp""strings"
)const (evernoteLoginURL = "https://www.evernote.com/Login.action"
)var (evernoteJSParamsExpr = regexp.MustCompile(`document.getElementById\("(.*)"\).value = "(.*)"`)evernoteRedirectExpr = regexp.MustCompile(`Redirecting to <a href="(.*)">`)errNoMatches   = errors.New("No matches")errRedirectURL = errors.New("Redirect URL not found")
)// EvernoteClient wraps all methods required to interact with the website.
type EvernoteClient struct {Username   stringPassword   stringhttpClient *http.Client// These parameters persist during the login process:hpts  stringhptsh string
}// NewEvernoteClient initializes a new Evernote client.
func NewEvernoteClient(username, password string) *EvernoteClient {// Allocate a new cookie jar to mimic the browser behavior:cookieJar, _ := cookiejar.New(nil)// Fill up basic data:c := &EvernoteClient{Username: username,Password: password,}// When initializing the http.Client, copy default values from http.DefaultClient// Pass a pointer to the cookie jar that was created earlier:c.httpClient = &http.Client{Transport:     http.DefaultTransport,CheckRedirect: http.DefaultClient.CheckRedirect,Jar:           cookieJar,Timeout:       http.DefaultClient.Timeout,}return c
}func (e *EvernoteClient) extractJSParams(body []byte) (err error) {matches := evernoteJSParamsExpr.FindAllSubmatch(body, -1)if len(matches) == 0 {return errNoMatches}for _, submatches := range matches {if len(submatches) < 3 {err = errNoMatchesbreak}key := submatches[1]val := submatches[2]if bytes.Compare(key, hptsKey) == 0 {e.hpts = string(val)}if bytes.Compare(key, hptshKey) == 0 {e.hptsh = string(val)}}return nil
}// Login handles the login action.
func (e *EvernoteClient) Login() error {// First step: fetch the login page as a browser visitor would do:res, err := e.httpClient.Get(evernoteLoginURL)if err != nil {return err}if res.Body == nil {return errors.New("No response body")}body, err := ioutil.ReadAll(res.Body)if err != nil {return err}err = e.extractJSParams(body)if err != nil {return err}// Second step: we have extracted the "hpts" and "hptsh" parameters// We send a request using only the username and setting "evaluateUsername":values := &url.Values{}values.Set("username", e.Username)values.Set("evaluateUsername", "")values.Set("analyticsLoginOrigin", "login_action")values.Set("clipperFlow", "false")values.Set("showSwitchService", "true")values.Set("hpts", e.hpts)values.Set("hptsh", e.hptsh)rawValues := values.Encode()req, err := http.NewRequest(http.MethodPost, evernoteLoginURL, bytes.NewBufferString(rawValues))if err != nil {return err}req.Header.Set("Accept", "application/json")req.Header.Set("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8")req.Header.Set("x-requested-with", "XMLHttpRequest")req.Header.Set("referer", evernoteLoginURL)res, err = e.httpClient.Do(req)if err != nil {return err}body, err = ioutil.ReadAll(res.Body)if err != nil {return err}bodyStr := string(body)if !strings.Contains(bodyStr, `"usePasswordAuth":true`) {return errors.New("Password auth not enabled")}// Third step: do the final request, append password to form data:values.Del("evaluateUsername")values.Set("password", e.Password)values.Set("login", "Sign in")rawValues = values.Encode()req, err = http.NewRequest(http.MethodPost, evernoteLoginURL, bytes.NewBufferString(rawValues))if err != nil {return err}req.Header.Set("Accept", "text/html")req.Header.Set("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8")req.Header.Set("x-requested-with", "XMLHttpRequest")req.Header.Set("referer", evernoteLoginURL)res, err = e.httpClient.Do(req)if err != nil {return err}// Check the body in order to find the redirect URL:body, err = ioutil.ReadAll(res.Body)if err != nil {return err}bodyStr = string(body)matches := evernoteRedirectExpr.FindAllStringSubmatch(bodyStr, -1)if len(matches) == 0 {return errRedirectURL}m := matches[0]if len(m) < 2 {return errRedirectURL}redirectURL := m[1]fmt.Println("Login is ok, redirect URL:", redirectURL)return nil
}
After you successfully get the redirect URL, you should be able to send authenticated requests as long as you keep using the HTTP client that was used for the login process, the cookie jar plays a very important role here.To call this code use:func main() {evernoteClient := NewEvernoteClient("user@company", "password")err := evernoteClient.Login()if err != nil {panic(err)}
}

package mainimport ("fmt""io/ioutil""net/http"
)// Login handles the login action.
func Login() {//生成client 参数为默认client := &http.Client{}//要访问的urlurl := "http://localhost:8000/hello"//要提交的请求req, _ := http.NewRequest("GET", url, nil)//最重要的一句，用户名和密码可随意写req.SetBasicAuth("aa", "bb")fmt.Println("POST访问")//返回结果res, _ := client.Do(req)defer res.Body.Close()fmt.Println("header:")header := res.Headerfmt.Println(header)fmt.Println("realm:")basicRealm := res.Header.Get("Www-Authenticate")fmt.Println(basicRealm)fmt.Println("body:")body, _ := ioutil.ReadAll(res.Body)fmt.Println(string(body))}func main() {   Login()
}

func (r *Request) SetBasicAuth(username, password string) {r.Header.Set("Authorization", "Basic "+basicAuth(username, password))
}

func basicAuth(username, password string) string {auth := username + ":" + passwordreturn base64.StdEncoding.EncodeToString([]byte(auth))
}

package mainimport ("encoding/base64""fmt""net/http""github.com/gocolly/colly"
)func basicAuth(username, password string) string {auth := username + ":" + passwordreturn base64.StdEncoding.EncodeToString([]byte(auth))
}
func main() {c := colly.NewCollector()h := http.Header{}h.Set("Authorization", "Basic "+basicAuth("aaaa", "bbbb"))c.OnResponse(func(r *colly.Response) {//fmt.Println(r)fmt.Println(string(r.Body))})c.Request("GET", "http://localhost:8000/hello", nil, nil, h)
}