Echo.StartTLS: accept string or []byte as parameters. (#1277)

If `certFile` or `keyFile` is `string` the values are treated as file paths.
If `certFile` or `keyFile` is `[]byte` the values are treated as the certificate or key as-is.

echo.go

@@ -43,6 +43,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"io/ioutil"
 	stdLog "log"
 	"net"
 	"net/http"
@@ -269,6 +270,7 @@ var (
 	ErrRendererNotRegistered       = errors.New("renderer not registered")
 	ErrInvalidRedirectCode         = errors.New("invalid redirect status code")
 	ErrCookieNotFound              = errors.New("cookie not found")
+	ErrInvalidCertOrKeyType        = errors.New("invalid cert or key type, must be string or []byte")
 )
 
 // Error handlers
@@ -605,20 +607,40 @@ func (e *Echo) Start(address string) error {
 }
 
 // StartTLS starts an HTTPS server.
-func (e *Echo) StartTLS(address string, certFile, keyFile string) (err error) {
-	if certFile == "" || keyFile == "" {
-		return errors.New("invalid tls configuration")
+// If `certFile` or `keyFile` is `string` the values are treated as file paths.
+// If `certFile` or `keyFile` is `[]byte` the values are treated as the certificate or key as-is.
+func (e *Echo) StartTLS(address string, certFile, keyFile interface{}) (err error) {
+	var cert []byte
+	if cert, err = filepathOrContent(certFile); err != nil {
+		return
 	}
+
+	var key []byte
+	if key, err = filepathOrContent(keyFile); err != nil {
+		return
+	}
+
 	s := e.TLSServer
 	s.TLSConfig = new(tls.Config)
 	s.TLSConfig.Certificates = make([]tls.Certificate, 1)
-	s.TLSConfig.Certificates[0], err = tls.LoadX509KeyPair(certFile, keyFile)
-	if err != nil {
+	if s.TLSConfig.Certificates[0], err = tls.X509KeyPair(cert, key); err != nil {
 		return
 	}
+
 	return e.startTLS(address)
 }
 
+func filepathOrContent(fileOrContent interface{}) (content []byte, err error) {
+	switch v := fileOrContent.(type) {
+	case string:
+		return ioutil.ReadFile(v)
+	case []byte:
+		return v, nil
+	default:
+		return nil, ErrInvalidCertOrKeyType
+	}
+}
+
 // StartAutoTLS starts an HTTPS server using certificates automatically installed from https://letsencrypt.org.
 func (e *Echo) StartAutoTLS(address string) error {
 	s := e.TLSServer

echo_test.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	stdContext "context"
 	"errors"
+	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
 	"reflect"
@@ -12,6 +13,7 @@ import (
 	"time"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 type (
@@ -428,6 +430,71 @@ func TestEchoStartTLS(t *testing.T) {
 	e.Close()
 }
 
+func TestEchoStartTLSByteString(t *testing.T) {
+	cert, err := ioutil.ReadFile("_fixture/certs/cert.pem")
+	require.NoError(t, err)
+	key, err := ioutil.ReadFile("_fixture/certs/key.pem")
+	require.NoError(t, err)
+
+	testCases := []struct {
+		cert        interface{}
+		key         interface{}
+		expectedErr error
+		name        string
+	}{
+		{
+			cert:        "_fixture/certs/cert.pem",
+			key:         "_fixture/certs/key.pem",
+			expectedErr: nil,
+			name:        `ValidCertAndKeyFilePath`,
+		},
+		{
+			cert:        cert,
+			key:         key,
+			expectedErr: nil,
+			name:        `ValidCertAndKeyByteString`,
+		},
+		{
+			cert:        cert,
+			key:         1,
+			expectedErr: ErrInvalidCertOrKeyType,
+			name:        `InvalidKeyType`,
+		},
+		{
+			cert:        0,
+			key:         key,
+			expectedErr: ErrInvalidCertOrKeyType,
+			name:        `InvalidCertType`,
+		},
+		{
+			cert:        0,
+			key:         1,
+			expectedErr: ErrInvalidCertOrKeyType,
+			name:        `InvalidCertAndKeyTypes`,
+		},
+	}
+
+	for _, test := range testCases {
+		test := test
+		t.Run(test.name, func(t *testing.T) {
+			e := New()
+			e.HideBanner = true
+
+			go func() {
+				err := e.StartTLS(":0", test.cert, test.key)
+				if test.expectedErr != nil {
+					require.EqualError(t, err, test.expectedErr.Error())
+				} else if err != http.ErrServerClosed { // Prevent the test to fail after closing the servers
+					require.NoError(t, err)
+				}
+			}()
+			time.Sleep(200 * time.Millisecond)
+
+			require.NoError(t, e.Close())
+		})
+	}
+}
+
 func TestEchoStartAutoTLS(t *testing.T) {
 	e := New()
 	errChan := make(chan error, 0)