com.vaadin.flow.component.littemplate.BundleLitParser Maven / Gradle / Ivy
/*
* Copyright 2000-2024 Vaadin Ltd.
*
* 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 com.vaadin.flow.component.littemplate;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.vaadin.flow.internal.StringUtil;
/**
* Parse statistics data provided by webpack.
*
* For internal use only. May be renamed or removed in a future release.
*
* @author Vaadin Ltd
* @since
*
* @see LitTemplateParser
*/
public final class BundleLitParser {
private static final Logger LOGGER = LoggerFactory
.getLogger(BundleLitParser.class);
/**
* Lit template pattern matches from the render() { until the
* last } character.
*
*
* render() {
*
* }
*
*
*
* render\(\)[\s]*\{ finds the template getter method and
* [\s\S]*\} ensures everything is captured until the last
* } character.
*/
private static final Pattern LIT_TEMPLATE_PATTERN = Pattern
.compile("render\\(\\)[\\s]*\\{[\\s\\S]*\\}");
/**
* Lit template pattern for html matches the return statement with html
* template. Used for the first match from render() {.
*
*
* return html`
* <style>
* .response { margin-top: 10px`; }
* </style>
* <paper-checkbox checked="${liked}">I like web components.</paper-checkbox>
*
* <div id="test" ?hidden="${liked}" class="response">Web components like you, too.</div>
* `;
* }
*
*
*
* return[\s]*html[\s]*(\`) finds the return statement
*
*
* ([\s\S]*?) captures all text until we encounter the end
* character with \1;} e.g. ';}
*/
private static final Pattern LIT_TEMPLATE_PATTERN_HTML = Pattern
.compile("return[\\s]*html[\\s]*(\\`)([\\s\\S]*?)\\1;[\\s]*\\}");
private static final String TEMPLATE_TAG_NAME = "template";
private BundleLitParser() {
}
/**
* Get the Lit template element for the given polymer template source.
*
* @param fileName
* name of the handled file
* @param source
* source js to get template element from
* @return template element or {code null} if not found
*/
public static Element parseLitTemplateElement(String fileName,
String source) {
Document templateDocument = null;
String content = StringUtil.removeComments(source);
Matcher renderMatcher = LIT_TEMPLATE_PATTERN.matcher(content);
if (renderMatcher.find()) {
String renderGroup = renderMatcher.group(0);
Matcher templateMatcher = LIT_TEMPLATE_PATTERN_HTML
.matcher(renderGroup);
// GroupCount should be at least 2 as the first group contains
// `|'|". Second group contains
// first "return html'" template contents.
if (templateMatcher.find() && templateMatcher.groupCount() >= 2) {
String group = templateMatcher.group(2);
LOGGER.trace("Found regular Lit template content was {}",
group);
templateDocument = Jsoup.parse(group);
LOGGER.trace("The parsed template document was {}",
templateDocument);
Element template = templateDocument
.createElement(TEMPLATE_TAG_NAME);
Element body = templateDocument.body();
templateDocument.body().children().stream()
.filter(node -> !node.equals(body))
.forEach(template::appendChild);
return template;
}
}
LOGGER.warn("No lit template data found in {} sources.", fileName);
return null;
}
}