/*
* Copyright 2016 Red Hat, Inc. and/or its affiliates
* and other contributors as indicated by the @author tags.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.keycloak.theme;
import freemarker.cache.URLTemplateLoader;
import freemarker.template.Configuration;
import freemarker.template.Template;
import org.keycloak.Config;
import java.io.IOException;
import java.io.StringWriter;
import java.io.Writer;
import java.net.URL;
import java.util.concurrent.ConcurrentHashMap;
/**
* @author <a href="mailto:sthorger@redhat.com">Stian Thorgersen</a>
*/
public class FreeMarkerUtil {
private ConcurrentHashMap<String, Template> cache;
public FreeMarkerUtil() {
if (Config.scope("theme").getBoolean("cacheTemplates", true)) {
cache = new ConcurrentHashMap<>();
}
}
public String processTemplate(Object data, String templateName, Theme theme) throws FreeMarkerException {
try {
Template template;
if (cache != null) {
String key = theme.getName() + "/" + templateName;
template = cache.get(key);
if (template == null) {
template = getTemplate(templateName, theme);
if (cache.putIfAbsent(key, template) != null) {
template = cache.get(key);
}
}
} else {
template = getTemplate(templateName, theme);
}
Writer out = new StringWriter();
template.process(data, out);
return out.toString();
} catch (Exception e) {
throw new FreeMarkerException("Failed to process template " + templateName, e);
}
}
private Template getTemplate(String templateName, Theme theme) throws IOException {
Configuration cfg = new Configuration();
cfg.setTemplateLoader(new ThemeTemplateLoader(theme));
return cfg.getTemplate(templateName, "UTF-8");
}
class ThemeTemplateLoader extends URLTemplateLoader {
private Theme theme;
public ThemeTemplateLoader(Theme theme) {
this.theme = theme;
}
@Override
protected URL getURL(String name) {
try {
return theme.getTemplate(name);
} catch (IOException e) {
return null;
}
}
}
}