RepoScriptSourceProvider.java

/*
 * RHQ Management Platform
 * Copyright 2012, Red Hat Middleware LLC, and individual contributors
 * as indicated by the @author tags. See the copyright.txt file in the
 * distribution for a full listing of individual contributors.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation version 2 of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

package org.rhq.bindings.script;

import java.io.ByteArrayInputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.net.URI;
import java.nio.charset.Charset;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.rhq.bindings.StandardBindings;
import org.rhq.bindings.client.RhqFacade;
import org.rhq.core.domain.content.Repo;
import org.rhq.core.domain.content.composite.PackageAndLatestVersionComposite;
import org.rhq.core.domain.criteria.PackageCriteria;
import org.rhq.core.domain.criteria.RepoCriteria;
import org.rhq.core.domain.util.PageList;
import org.rhq.enterprise.server.content.ContentManagerRemote;
import org.rhq.enterprise.server.content.RepoManagerRemote;
import org.rhq.enterprise.server.util.CriteriaQuery;
import org.rhq.enterprise.server.util.CriteriaQueryExecutor;

/**
 * The implementation of script source provider that is able to locate the script files
 * in the repositories on the RHQ server.
 * <p>
 * The URI looks like:<br>
 * <code>
 * rhq://repositories/repositoryName/scriptFile
 * </code>
 *  
 * @author Lukas Krejci
 */
public class RepoScriptSourceProvider extends BaseRhqSchemeScriptSourceProvider implements
    StandardBindings.RhqFacadeChangeListener {

    private static final Log LOG = LogFactory.getLog(RepoScriptSourceProvider.class);

    private static final String AUTHORITY = "repositories";

    private RhqFacade rhqFacade;

    public RepoScriptSourceProvider() {
        super(AUTHORITY);
    }
    
    @Override
    public void rhqFacadeChanged(StandardBindings bindings) {
        this.rhqFacade = bindings.getAssociatedRhqFacade();
    }

    @Override
    protected Reader doGetScriptSource(URI scriptUri) {
        if (rhqFacade == null) {
            return null;
        }

        String path = scriptUri.getPath().substring(1); //remove the leading / from the path

        int slashIdx = path.indexOf('/');

        if (slashIdx == -1) {
            return null;
        }

        String repoName = path.substring(0, slashIdx);
        String scriptName = path.substring(slashIdx + 1);

        try {
            final RepoManagerRemote repoManager = rhqFacade.getProxy(RepoManagerRemote.class);

            final RepoCriteria repoCrit = new RepoCriteria();
            repoCrit.addFilterName(repoName);

            //Use CriteriaQuery to automatically chunk/page through criteria query results
            CriteriaQueryExecutor<Repo, RepoCriteria> queryExecutor = new CriteriaQueryExecutor<Repo, RepoCriteria>() {
                @Override
                public PageList<Repo> execute(RepoCriteria criteria) {
                    return repoManager.findReposByCriteria(rhqFacade.getSubject(), repoCrit);
                }
            };

            CriteriaQuery<Repo, RepoCriteria> repos = new CriteriaQuery<Repo, RepoCriteria>(repoCrit, queryExecutor);

            if (!repos.iterator().hasNext()) {
                return null;
            }

            final ContentManagerRemote contentManager = rhqFacade.getProxy(ContentManagerRemote.class);

            for (Repo repo : repos) {
                final PackageCriteria pCrit = new PackageCriteria();
                pCrit.addFilterName(scriptName);
                pCrit.addFilterRepoId(repo.getId());

                //Use CriteriaQuery to automatically chunk/page through criteria query results
                CriteriaQueryExecutor<PackageAndLatestVersionComposite, PackageCriteria> pQueryExecutor = new CriteriaQueryExecutor<PackageAndLatestVersionComposite, PackageCriteria>() {
                    @Override
                    public PageList<PackageAndLatestVersionComposite> execute(PackageCriteria criteria) {
                        return contentManager.findPackagesWithLatestVersion(rhqFacade.getSubject(), pCrit);
                    }
                };

                CriteriaQuery<PackageAndLatestVersionComposite, PackageCriteria> pvs = new CriteriaQuery<PackageAndLatestVersionComposite, PackageCriteria>(
                    pCrit, pQueryExecutor);

                //                if (!pvs.iterator().hasNext()) {
                if (pvs.iterator().hasNext()) {
                    PackageAndLatestVersionComposite pv = pvs.iterator().next();

                    byte[] bytes = repoManager.getPackageVersionBytes(rhqFacade.getSubject(), repo.getId(), pv
                        .getLatestPackageVersion().getId());

                    return new InputStreamReader(new ByteArrayInputStream(bytes), Charset.forName("UTF-8"));
                }
            }
        } catch (Exception e) {
            LOG.debug("Failed to download bytes for the script: " + scriptUri.toString(), e);
        }

        return null;
    }

}