org.apache.ambari.server.checks.AbstractCheckDescriptor.java Source code

Introduction

Here is the source code for org.apache.ambari.server.checks.AbstractCheckDescriptor.java

Source

/*
 * 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.ambari.server.checks;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

import org.apache.ambari.server.AmbariException;
import org.apache.ambari.server.api.services.AmbariMetaInfo;
import org.apache.ambari.server.controller.PrereqCheckRequest;
import org.apache.ambari.server.orm.dao.HostVersionDAO;
import org.apache.ambari.server.orm.dao.RepositoryVersionDAO;
import org.apache.ambari.server.state.Cluster;
import org.apache.ambari.server.state.Clusters;
import org.apache.ambari.server.state.ServiceInfo;
import org.apache.ambari.server.state.stack.PrereqCheckType;
import org.apache.ambari.server.state.stack.PrerequisiteCheck;
import org.apache.ambari.server.state.stack.upgrade.RepositoryVersionHelper;
import org.apache.commons.lang.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.inject.Inject;
import com.google.inject.Provider;

/**
 * Describes prerequisite check.
 */
public abstract class AbstractCheckDescriptor {

    private static final Logger LOG = LoggerFactory.getLogger(AbstractCheckDescriptor.class);

    protected static final String DEFAULT = "default";

    @Inject
    Provider<Clusters> clustersProvider;

    @Inject
    Provider<HostVersionDAO> hostVersionDaoProvider;

    @Inject
    Provider<RepositoryVersionDAO> repositoryVersionDaoProvider;

    @Inject
    Provider<RepositoryVersionHelper> repositoryVersionHelper;

    @Inject
    Provider<AmbariMetaInfo> ambariMetaInfo;

    private CheckDescription m_description;

    /**
     * Constructor.
     *
     * @param description description
     */
    protected AbstractCheckDescriptor(CheckDescription description) {
        m_description = description;
    }

    /**
     * Tests if the prerequisite check is applicable to given cluster. By default returns true.
     *
     * @param request prerequisite check request
     * @return true if check should be performed
     *
     * @throws org.apache.ambari.server.AmbariException if server error happens
     */
    public boolean isApplicable(PrereqCheckRequest request) throws AmbariException {
        return true;
    }

    /**
     * Executes check against given cluster.
     *
     * @param prerequisiteCheck dto for upgrade check results
     * @param request pre upgrade check request
     *
     * @throws AmbariException if server error happens
     */
    public abstract void perform(PrerequisiteCheck prerequisiteCheck, PrereqCheckRequest request)
            throws AmbariException;

    public CheckDescription getDescription() {
        return m_description;
    }

    public PrereqCheckType getType() {
        return m_description.getType();
    }

    /**
     * Gets the default fail reason
     * @param prerequisiteCheck the check being performed
     * @param request           the request
     * @return the failure string
     */
    protected String getFailReason(PrerequisiteCheck prerequisiteCheck, PrereqCheckRequest request) {
        return getFailReason(DEFAULT, prerequisiteCheck, request);
    }

    /**
     * Gets the fail reason
     * @param key               the failure text key
     * @param prerequisiteCheck the check being performed
     * @param request           the request
     * @return the failure string
     */
    protected String getFailReason(String key, PrerequisiteCheck prerequisiteCheck, PrereqCheckRequest request) {
        String fail = m_description.getFail(key);

        if (-1 != fail.indexOf("{{version}}") && null != request.getRepositoryVersion()) {
            fail = fail.replace("{{version}}", request.getRepositoryVersion());
        }

        if (-1 != fail.indexOf("{{fails}}")) {
            List<String> names = prerequisiteCheck.getFailedOn();

            if (getDescription().getType() == PrereqCheckType.SERVICE) {
                Clusters clusters = clustersProvider.get();
                AmbariMetaInfo metaInfo = ambariMetaInfo.get();

                try {
                    Cluster c = clusters.getCluster(request.getClusterName());
                    Map<String, ServiceInfo> services = metaInfo.getServices(
                            c.getDesiredStackVersion().getStackName(),
                            c.getDesiredStackVersion().getStackVersion());

                    List<String> displays = new ArrayList<String>();
                    for (String name : names) {
                        if (services.containsKey(name)) {
                            displays.add(services.get(name).getDisplayName());
                        } else {
                            displays.add(name);
                        }
                    }
                    names = displays;
                } catch (Exception e) {
                    LOG.warn("Could not load service info map");
                }

                fail = fail.replace("{{fails}}", formatEntityList(names));

            }

        }

        return fail;
    }

    /**
     * Formats lists of given entities to human readable form:
     * [entity1] -> {entity1} {noun}
     * [entity1, entity2] -> {entity1} and {entity2} {noun}s
     * [entity1, entity2, entity3] -> {entity1}, {entity2} and {entity3} {noun}s
     * The noun for the entities is taken from check type, it may be cluster, service or host.
     *
     * @param entities list of entities to format
     * @return formatted entity list
     */
    protected String formatEntityList(List<String> entities) {
        if (entities == null || entities.isEmpty()) {
            return "";
        }
        final StringBuilder formatted = new StringBuilder(StringUtils.join(entities, ", "));
        if (entities.size() > 1) {
            formatted.replace(formatted.lastIndexOf(","), formatted.lastIndexOf(",") + 1, " and");
        }

        return formatted.toString();
    }

}