MM-10731 Revert site url kill server (#8877)

* Revert "MM-9983 Requiring SiteURL to be set. (#8769)"

This reverts commit 0432f995ec.

* Add log message for SiteURL not being set.

model/config.go

@@ -1900,10 +1900,18 @@ func (o *Config) SetDefaults() {
 }
 
 func (o *Config) IsValid() *AppError {
+	if len(*o.ServiceSettings.SiteURL) == 0 && *o.EmailSettings.EnableEmailBatching {
+		return NewAppError("Config.IsValid", "model.config.is_valid.site_url_email_batching.app_error", nil, "", http.StatusBadRequest)
+	}
+
 	if *o.ClusterSettings.Enable && *o.EmailSettings.EnableEmailBatching {
 		return NewAppError("Config.IsValid", "model.config.is_valid.cluster_email_batching.app_error", nil, "", http.StatusBadRequest)
 	}
 
+	if len(*o.ServiceSettings.SiteURL) == 0 && *o.ServiceSettings.AllowCookiesForSubdomains {
+		return NewAppError("Config.IsValid", "Allowing cookies for subdomains requires SiteURL to be set.", nil, "", http.StatusBadRequest)
+	}
+
 	if err := o.TeamSettings.isValid(); err != nil {
 		return err
 	}
@@ -2209,6 +2217,12 @@ func (ss *ServiceSettings) isValid() *AppError {
 		return NewAppError("Config.IsValid", "model.config.is_valid.login_attempts.app_error", nil, "", http.StatusBadRequest)
 	}
 
+	if len(*ss.SiteURL) != 0 {
+		if _, err := url.ParseRequestURI(*ss.SiteURL); err != nil {
+			return NewAppError("Config.IsValid", "model.config.is_valid.site_url.app_error", nil, "", http.StatusBadRequest)
+		}
+	}
+
 	if len(*ss.WebsocketURL) != 0 {
 		if _, err := url.ParseRequestURI(*ss.WebsocketURL); err != nil {
 			return NewAppError("Config.IsValid", "model.config.is_valid.websocket_url.app_error", nil, "", http.StatusBadRequest)

model/config_test.go

@@ -82,13 +82,6 @@ func TestConfigDefaultFileSettingsS3SSE(t *testing.T) {
 	}
 }
 
-func TestConfigDefaultSiteURL(t *testing.T) {
-	c1 := Config{}
-	c1.SetDefaults()
-
-	assert.Equal(t, "", *c1.ServiceSettings.SiteURL, "SiteURL should be empty by default.")
-}
-
 func TestConfigDefaultServiceSettingsExperimentalGroupUnreadChannels(t *testing.T) {
 	c1 := Config{}
 	c1.SetDefaults()