Add new linters (#486)

* add new linters and fix issues

* fix deprecated warnings

* simplify return

* update CHANGELOG

* fix staticcheck issues

* remove a deprecated linter, minor fixes of variable initialization

pkg/logger/logger.go

@@ -139,10 +139,10 @@ func (l *Logger) Output(calldepth int, message string) {
 	l.writer.Write([]byte("\n"))
 }
 
-// PrintAuth writes auth info to the logger. Requires an http.Request to
+// PrintAuthf writes auth info to the logger. Requires an http.Request to
 // log request details. Remaining arguments are handled in the manner of
 // fmt.Sprintf. Writes a final newline to the end of every message.
-func (l *Logger) PrintAuth(username string, req *http.Request, status AuthStatus, format string, a ...interface{}) {
+func (l *Logger) PrintAuthf(username string, req *http.Request, status AuthStatus, format string, a ...interface{}) {
 	if !l.authEnabled {
 		return
 	}
@@ -166,7 +166,7 @@ func (l *Logger) PrintAuth(username string, req *http.Request, status AuthStatus
 		Timestamp:     FormatTimestamp(now),
 		UserAgent:     fmt.Sprintf("%q", req.UserAgent()),
 		Username:      username,
-		Status:        fmt.Sprintf("%s", status),
+		Status:        string(status),
 		Message:       fmt.Sprintf(format, a...),
 	})
 
@@ -185,7 +185,7 @@ func (l *Logger) PrintReq(username, upstream string, req *http.Request, url url.
 		return
 	}
 
-	duration := float64(time.Now().Sub(ts)) / float64(time.Second)
+	duration := float64(time.Since(ts)) / float64(time.Second)
 
 	if username == "" {
 		username = "-"
@@ -481,7 +481,7 @@ func Panicln(v ...interface{}) {
 // PrintAuthf writes authentication details to the standard logger.
 // Arguments are handled in the manner of fmt.Printf.
 func PrintAuthf(username string, req *http.Request, status AuthStatus, format string, a ...interface{}) {
-	std.PrintAuth(username, req, status, format, a...)
+	std.PrintAuthf(username, req, status, format, a...)
 }
 
 // PrintReq writes request details to the standard logger.

pkg/requests/requests_test.go

@@ -88,9 +88,9 @@ func TestRequestUnparsedResponseUsingAccessTokenParameter(t *testing.T) {
 
 	response, err := RequestUnparsedResponse(
 		backend.URL+"?access_token=my_token", nil)
+	assert.Equal(t, nil, err)
 	defer response.Body.Close()
 
-	assert.Equal(t, nil, err)
 	assert.Equal(t, 200, response.StatusCode)
 	body, err := ioutil.ReadAll(response.Body)
 	assert.Equal(t, nil, err)
@@ -124,9 +124,9 @@ func TestRequestUnparsedResponseUsingHeaders(t *testing.T) {
 	headers := make(http.Header)
 	headers.Set("Auth", "my_token")
 	response, err := RequestUnparsedResponse(backend.URL, headers)
+	assert.Equal(t, nil, err)
 	defer response.Body.Close()
 
-	assert.Equal(t, nil, err)
 	assert.Equal(t, 200, response.StatusCode)
 	body, err := ioutil.ReadAll(response.Body)
 	assert.Equal(t, nil, err)

pkg/sessions/cookie/session_store.go

@@ -52,11 +52,11 @@ func (s *SessionStore) Load(req *http.Request) (*sessions.SessionState, error) {
 	c, err := loadCookie(req, s.CookieOptions.CookieName)
 	if err != nil {
 		// always http.ErrNoCookie
-		return nil, fmt.Errorf("Cookie %q not present", s.CookieOptions.CookieName)
+		return nil, fmt.Errorf("cookie %q not present", s.CookieOptions.CookieName)
 	}
 	val, _, ok := encryption.Validate(c, s.CookieOptions.CookieSecret, s.CookieOptions.CookieExpire)
 	if !ok {
-		return nil, errors.New("Cookie Signature not valid")
+		return nil, errors.New("cookie signature not valid")
 	}
 
 	session, err := utils.SessionFromCookie(val, s.CookieCipher)
@@ -69,8 +69,6 @@ func (s *SessionStore) Load(req *http.Request) (*sessions.SessionState, error) {
 // Clear clears any saved session information by writing a cookie to
 // clear the session
 func (s *SessionStore) Clear(rw http.ResponseWriter, req *http.Request) error {
-	var cookies []*http.Cookie
-
 	// matches CookieName, CookieName_<number>
 	var cookieNameRegex = regexp.MustCompile(fmt.Sprintf("^%s(_\\d+)?$", s.CookieOptions.CookieName))
 
@@ -79,7 +77,6 @@ func (s *SessionStore) Clear(rw http.ResponseWriter, req *http.Request) error {
 			clearCookie := s.makeCookie(req, c.Name, "", time.Hour*-1, time.Now())
 
 			http.SetCookie(rw, clearCookie)
-			cookies = append(cookies, clearCookie)
 		}
 	}
 
@@ -174,7 +171,7 @@ func loadCookie(req *http.Request, cookieName string) (*http.Cookie, error) {
 		}
 	}
 	if len(cookies) == 0 {
-		return nil, fmt.Errorf("Could not find cookie %s", cookieName)
+		return nil, fmt.Errorf("could not find cookie %s", cookieName)
 	}
 	return joinCookies(cookies)
 }

pkg/sessions/redis/redis_store.go

@@ -79,7 +79,7 @@ func newRedisCmdable(opts options.RedisStoreOptions) (Client, error) {
 		return nil, fmt.Errorf("unable to parse redis url: %s", err)
 	}
 
-	if opts.RedisInsecureTLS != false {
+	if opts.RedisInsecureTLS {
 		opt.TLSConfig.InsecureSkipVerify = true
 	}
 
@@ -149,7 +149,7 @@ func (store *SessionStore) Load(req *http.Request) (*sessions.SessionState, erro
 
 	val, _, ok := encryption.Validate(requestCookie, store.CookieOptions.CookieSecret, store.CookieOptions.CookieExpire)
 	if !ok {
-		return nil, fmt.Errorf("Cookie Signature not valid")
+		return nil, fmt.Errorf("cookie signature not valid")
 	}
 	ctx := req.Context()
 	session, err := store.loadSessionFromString(ctx, val)
@@ -209,7 +209,7 @@ func (store *SessionStore) Clear(rw http.ResponseWriter, req *http.Request) erro
 
 	val, _, ok := encryption.Validate(requestCookie, store.CookieOptions.CookieSecret, store.CookieOptions.CookieExpire)
 	if !ok {
-		return fmt.Errorf("Cookie Signature not valid")
+		return fmt.Errorf("cookie signature not valid")
 	}
 
 	// We only return an error if we had an issue with redis