DefaultHTMLTemplate.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.apache.dolphinscheduler.alert.template.impl;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.node.ArrayNode;
import org.apache.dolphinscheduler.alert.template.AlertTemplate;
import org.apache.dolphinscheduler.alert.utils.Constants;
import org.apache.dolphinscheduler.common.enums.ShowType;
import org.apache.dolphinscheduler.common.utils.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.dolphinscheduler.common.utils.*;

import java.util.*;

import static org.apache.dolphinscheduler.common.utils.Preconditions.*;

/**
 * the default html alert message template
 */
public class DefaultHTMLTemplate implements AlertTemplate {

    public static final Logger logger = LoggerFactory.getLogger(DefaultHTMLTemplate.class);

    @Override
    public String getMessageFromTemplate(String content, ShowType showType,boolean showAll) {

        switch (showType){
            case TABLE:
                return getTableTypeMessage(content,showAll);
            case TEXT:
                return getTextTypeMessage(content,showAll);
            default:
                throw new IllegalArgumentException(String.format("not support showType: %s in DefaultHTMLTemplate",showType));
        }
    }

    /**
     * get alert message which type is TABLE
     * @param content message content
     * @param showAll weather to show all
     * @return alert message
     */
    private String getTableTypeMessage(String content,boolean showAll){

        if (StringUtils.isNotEmpty(content)){
            List<LinkedHashMap> mapItemsList = JSONUtils.toList(content, LinkedHashMap.class);

            if(!showAll && mapItemsList.size() > Constants.NUMBER_1000){
                mapItemsList = mapItemsList.subList(0,Constants.NUMBER_1000);
            }

            StringBuilder contents = new StringBuilder(200);

            boolean flag = true;

            String title = "";
            for (LinkedHashMap mapItems : mapItemsList){

                Set<Map.Entry<String, Object>> entries = mapItems.entrySet();

                Iterator<Map.Entry<String, Object>> iterator = entries.iterator();

                StringBuilder t = new StringBuilder(Constants.TR);
                StringBuilder cs = new StringBuilder(Constants.TR);
                while (iterator.hasNext()){

                    Map.Entry<String, Object> entry = iterator.next();
                    t.append(Constants.TH).append(entry.getKey()).append(Constants.TH_END);
                    cs.append(Constants.TD).append(String.valueOf(entry.getValue())).append(Constants.TD_END);

                }
                t.append(Constants.TR_END);
                cs.append(Constants.TR_END);
                if (flag){
                    title = t.toString();
                }
                flag = false;
                contents.append(cs);
            }

            return getMessageFromHtmlTemplate(title,contents.toString());
        }

        return content;
    }

    /**
     * get alert message which type is TEXT
     * @param content message content
     * @param showAll weather to show all
     * @return alert message
     */
    private String getTextTypeMessage(String content,boolean showAll){

        if (StringUtils.isNotEmpty(content)){
            ArrayNode list = JSONUtils.parseArray(content);
            StringBuilder contents = new StringBuilder(100);
            for (JsonNode jsonNode : list){
                contents.append(Constants.TR);
                contents.append(Constants.TD).append(jsonNode.toString()).append(Constants.TD_END);
                contents.append(Constants.TR_END);
            }

            return getMessageFromHtmlTemplate(null,contents.toString());

        }

        return content;
    }

    /**
     * get alert message from a html template
     * @param title     message title
     * @param content   message content
     * @return alert message which use html template
     */
    private String getMessageFromHtmlTemplate(String title,String content){

        checkNotNull(content);
        String htmlTableThead = StringUtils.isEmpty(title) ? "" : String.format("<thead>%s</thead>\n",title);

        return "<html>\n" +
                "    <head>\n" +
                "        <title>dolphinscheduler</title>\n" +
                "        <meta name='Keywords' content=''>\n" +
                "        <meta name='Description' content=''>\n" +
                "        <style type=\"text/css\">\n" +
                "            table {margin-top:0px;padding-top:0px;border:1px solid;font-size: 14px;color: #333333;border-width: 1px;border-color: #666666;border-collapse: collapse;}\n" +
                "            table th {border-width: 1px;padding: 8px;border-style: solid;border-color: #666666;background-color: #dedede;text-align: right;}\n" +
                "            table td {border-width: 1px;padding: 8px;border-style: solid;border-color: #666666;background-color: #ffffff;text-align: right;}\n" +
                "        </style>\n" +
                "    </head>\n" +
                "    <body style=\"margin:0;padding:0\">\n" +
                "        <table border=\"1px\" cellpadding=\"5px\" cellspacing=\"-10px\">\n" + htmlTableThead + content +
                "        </table>\n" +
                "    </body>\n" +
                "</html>";
    }
}