http_proxy(error): make error messages to be lower case

http_proxy_errors.go

@@ -13,6 +13,7 @@ import (
 	"fmt"
 	"net"
 	"net/http"
+	"strings"
 
 	"github.com/saucelabs/forwarder/internal/martian/proxyutil"
 )
@@ -50,7 +51,7 @@ func (hp *HTTPProxy) errorResponse(req *http.Request, err error) *http.Response
 	}
 	if code == 0 {
 		code = http.StatusInternalServerError
-		msg = "An unexpected error occurred"
+		msg = "an unexpected error occurred"
 		label = "unexpected_error"
 	}
 
@@ -78,10 +79,10 @@ func handleNetError(_ *http.Request, err error) (code int, msg, label string) {
 	if errors.As(err, &netErr) {
 		if netErr.Timeout() {
 			code = http.StatusGatewayTimeout
-			msg = "Timed out connecting to remote host"
+			msg = "timed out connecting to remote host"
 		} else {
 			code = http.StatusBadGateway
-			msg = "Failed to connect to remote host"
+			msg = "failed to connect to remote host"
 		}
 		label = "net_" + netErr.Op
 	}
@@ -93,7 +94,7 @@ func handleTLSRecordHeader(_ *http.Request, err error) (code int, msg, label str
 	var headerErr *tls.RecordHeaderError
 	if errors.As(err, &headerErr) {
 		code = http.StatusBadGateway
-		msg = "TLS handshake failed"
+		msg = "tls handshake failed"
 		label = "tls_record_header"
 	}
 
@@ -104,7 +105,7 @@ func handleTLSCertificateError(_ *http.Request, err error) (code int, msg, label
 	var certErr *tls.CertificateVerificationError
 	if errors.As(err, &certErr) {
 		code = http.StatusBadGateway
-		msg = "TLS handshake failed"
+		msg = "tls handshake failed"
 		label = "tls_certificate"
 	}
 
@@ -129,7 +130,7 @@ func handleStatusText(req *http.Request, err error) (code int, msg, label string
 	if req.URL.Scheme == "https" && err != nil {
 		for i := 400; i < 600; i++ {
 			if err.Error() == http.StatusText(i) {
-				return i, err.Error(), "https_status_text"
+				return i, strings.ToLower(err.Error()), "https_status_text"
 			}
 		}
 	}