templates: Parse host successfully when port is implicit (fixes #292)

middleware/context.go

@@ -97,6 +97,10 @@ func (c Context) URI() string {
 func (c Context) Host() (string, error) {
 	host, _, err := net.SplitHostPort(c.Req.Host)
 	if err != nil {
+		if !strings.Contains(c.Req.Host, ":") {
+			// common with sites served on the default port 80
+			return c.Req.Host, nil
+		}
 		return "", err
 	}
 	return host, nil

middleware/context_test.go

@@ -232,8 +232,13 @@ func TestHost(t *testing.T) {
 		},
 		{
 			input:        "localhost",
+			expectedHost: "localhost",
+			shouldErr:    false,
+		},
+		{
+			input:        "[::]",
 			expectedHost: "",
-			shouldErr:    true, // missing port in address
+			shouldErr:    true,
 		},
 	}
 
@@ -258,6 +263,11 @@ func TestPort(t *testing.T) {
 			expectedPort: "",
 			shouldErr:    true, // missing port in address
 		},
+		{
+			input:        ":8080",
+			expectedPort: "8080",
+			shouldErr:    false,
+		},
 	}
 
 	for _, test := range tests {