core/src/main/java/org/apache/oozie/servlet/V2AdminServlet.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.oozie.servlet;

import java.io.IOException;
import java.io.Writer;
import java.util.Map;
import java.util.Properties;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import io.prometheus.client.CollectorRegistry;
import io.prometheus.client.exporter.common.TextFormat;
import org.apache.hadoop.conf.Configuration;
import org.apache.oozie.ErrorCode;
import org.apache.oozie.client.rest.JMSConnectionInfoBean;
import org.apache.oozie.client.rest.JsonBean;
import org.apache.oozie.jms.JMSConnectionInfo;
import org.apache.oozie.jms.JMSJobEventListener;
import org.apache.oozie.service.InstrumentationService;
import org.apache.oozie.service.JMSTopicService;
import org.apache.oozie.service.JobsConcurrencyService;
import org.apache.oozie.service.Services;
import org.apache.oozie.util.Instrumentation;
import org.apache.oozie.util.MetricsInstrumentation;

/**
 * V2 admin servlet
 *
 */
public class V2AdminServlet extends V1AdminServlet {

    private static final long serialVersionUID = 1L;
    private static final String INSTRUMENTATION_NAME = "v2admin";
    private static MetricsInstrumentation metricsInstrumentation = null;

    public V2AdminServlet() {
        super(INSTRUMENTATION_NAME);

        // If MetricsInstrumentationService is used, we will enable the metrics endpoint and disable the instrumentation endpoint
        Services services = Services.get();
        if (services != null) {
            Instrumentation instrumentation = services.get(InstrumentationService.class).get();
            if (instrumentation instanceof MetricsInstrumentation) {
                metricsInstrumentation = (MetricsInstrumentation) instrumentation;
            } else {
                metricsInstrumentation = null;
            }
        }
    }

    @Override
    protected JsonBean getJMSConnectionInfo(HttpServletRequest request, HttpServletResponse response)
            throws XServletException, IOException {
        Configuration conf = Services.get().getConf();
        JMSTopicService jmsTopicService = Services.get().get(JMSTopicService.class);
        String connectionProperties = conf.get(JMSJobEventListener.JMS_CONNECTION_PROPERTIES);
        if (connectionProperties == null) {
            throw new XServletException(HttpServletResponse.SC_BAD_REQUEST, ErrorCode.E1601,
                    "JMS connection property is not defined");
        }
        JMSConnectionInfoBean jmsBean = new JMSConnectionInfoBean();
        JMSConnectionInfo jmsInfo = new JMSConnectionInfo(connectionProperties);
        Properties jmsInfoProps = jmsInfo.getJNDIProperties();
        jmsInfoProps.remove("java.naming.security.principal");
        jmsBean.setJNDIProperties(jmsInfoProps);
        if (jmsTopicService != null) {
            jmsBean.setTopicPrefix(jmsTopicService.getTopicPrefix());
            jmsBean.setTopicPatternProperties(jmsTopicService.getTopicPatternProperties());
        }
        else {
            throw new XServletException(
                    HttpServletResponse.SC_BAD_REQUEST,
                    ErrorCode.E1601,
                    "JMSTopicService is not initialized. JMS notification"
                            + "may not be enabled");
        }
        return jmsBean;
    }

    @Override
    protected Map<String, String> getOozieURLs() throws XServletException {
        Map<String, String> serverUrls = null;
        try {
            serverUrls = Services.get().get(JobsConcurrencyService.class).getServerUrls();
        } catch (Exception ex) {
            throw new XServletException(HttpServletResponse.SC_BAD_REQUEST, ErrorCode.E0307, ex.getMessage(), ex);
        }
        return serverUrls;
    }

    @Override
    protected void sendMetricsResponse(HttpServletResponse response) throws IOException, XServletException {
        if (metricsInstrumentation != null) {
            response.setStatus(HttpServletResponse.SC_OK);
            response.setContentType(JSON_UTF8);
            try {
                metricsInstrumentation.writeJSONResponse(response.getOutputStream());
            } finally {
                response.getOutputStream().close();
            }
        } else {
            response.setStatus(HttpServletResponse.SC_SERVICE_UNAVAILABLE);
            response.sendError(HttpServletResponse.SC_SERVICE_UNAVAILABLE, "MetricsInstrumentationService is not running");
        }
    }

    @Override
    protected void sendPrometheusResponse(HttpServletResponse response) throws IOException, XServletException {
        if (metricsInstrumentation != null) {
            response.setStatus(HttpServletResponse.SC_OK);
            response.setContentType(TextFormat.CONTENT_TYPE_004);
            Writer writer = response.getWriter();
            TextFormat.write004(writer, CollectorRegistry.defaultRegistry.metricFamilySamples());
            writer.flush();
        } else {
            response.setStatus(HttpServletResponse.SC_SERVICE_UNAVAILABLE);
            response.sendError(HttpServletResponse.SC_SERVICE_UNAVAILABLE, "MetricsInstrumentationService is not running");
        }
    }

    @Override
    protected void sendInstrumentationResponse(HttpServletResponse response, Instrumentation instr)
            throws IOException, XServletException {
        if (metricsInstrumentation == null) {
            super.sendInstrumentationResponse(response, instr);
        } else {
            response.setStatus(HttpServletResponse.SC_SERVICE_UNAVAILABLE);
            response.sendError(HttpServletResponse.SC_SERVICE_UNAVAILABLE, "InstrumentationService is not running");
        }
    }
}