elastic-grid

/**

 * Copyright (C) 2007-2008 Elastic Grid, LLC.

 *

 * This file is part of Elastic Grid.

 *

 * Elastic Grid is free software: you can redistribute it and/or modify

 * it under the terms of the GNU Lesser General Public License as

 * published by the Free Software Foundation, either version 3 of the

 * License, or any later version.

 *

 * Elastic Grid 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 Lesser General Public License

 * along with Elastic Grid.  If not, see <http://www.gnu.org/licenses/>.

 */

package com.elasticgrid.rest;

import com.elasticgrid.cluster.ClusterManager;

import com.elasticgrid.model.Cluster;

import com.elasticgrid.model.ClusterProvisioning;

import com.elasticgrid.model.internal.Clusters;

import org.jibx.runtime.JiBXException;

import org.restlet.Context;

import org.restlet.data.Form;

import org.restlet.data.MediaType;

import org.restlet.data.Request;

import org.restlet.data.Response;

import org.restlet.data.Status;

import org.restlet.ext.jibx.JibxRepresentation;

import org.restlet.ext.wadl.DocumentationInfo;

import org.restlet.ext.wadl.MethodInfo;

import org.restlet.ext.wadl.ParameterInfo;

import org.restlet.ext.wadl.ParameterStyle;

import org.restlet.ext.wadl.RepresentationInfo;

import org.restlet.ext.wadl.WadlResource;

import org.restlet.resource.Representation;

import org.restlet.resource.ResourceException;

import org.restlet.resource.Variant;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.context.annotation.Scope;

import org.springframework.stereotype.Component;

import java.io.IOException;

import java.util.Arrays;

import java.util.List;

import java.util.concurrent.TimeoutException;

@Component

@Scope("prototype")

public class ClustersResource extends WadlResource {

    @Autowired

    private ClusterManager<Cluster> clusterManager;

    @Override

    public void init(Context context, Request request, Response response) {

        super.init(context, request, response);

        // Allow modifications of this resource via POST requests

        setModifiable(true);

        // Declare the kind of representations supported by this resource

        getVariants().add(new Variant(MediaType.APPLICATION_XML));

    }

    /**

     * Handle GET requests: describe all clusters.

     */

    @Override

    public Representation represent(Variant variant) throws ResourceException {

        List<Cluster> clusters;

        try {

            clusters = clusterManager.findClusters();

            return new JibxRepresentation<Clusters>(MediaType.APPLICATION_XML, new Clusters(clusters), "ElasticGridREST");

        } catch (Exception e) {

            e.printStackTrace();

            throw new ResourceException(Status.SERVER_ERROR_SERVICE_UNAVAILABLE, e);

        }

    }

    /**

     * Handle PUT requests: start a new cluster.

     */

    @Override

    @SuppressWarnings({"MismatchedQueryAndUpdateOfCollection"})

    public void acceptRepresentation(Representation entity) throws ResourceException {

        String clusterName = null;

        int numberOfMonitors = 1;

        int numberOfAgents = 0;

        if (MediaType.APPLICATION_XML.equals(entity.getMediaType())) {

            try {

                JibxRepresentation<ClusterProvisioning> representation =

                        new JibxRepresentation<ClusterProvisioning>(entity, ClusterProvisioning.class, "ElasticGridREST");

                ClusterProvisioning clusterProvisioning = representation.getObject();

                clusterName = clusterProvisioning.getClusterName();

                numberOfMonitors = clusterProvisioning.getNumberOfMonitors();

                numberOfAgents = clusterProvisioning.getNumberOfAgents();

            } catch (JiBXException e) {

                e.printStackTrace();

                throw new ResourceException(Status.CLIENT_ERROR_UNPROCESSABLE_ENTITY, e);

            } catch (IOException e) {

                e.printStackTrace();

                throw new ResourceException(Status.CLIENT_ERROR_UNPROCESSABLE_ENTITY, e);

            }

        } else if (MediaType.APPLICATION_WWW_FORM.equals(entity.getMediaType())) {

            Form form = new Form(entity);

            clusterName = form.getFirstValue("clusterName");

            numberOfMonitors = Integer.parseInt(form.getFirstValue("numberOfMonitors"));

            numberOfAgents = Integer.parseInt(form.getFirstValue("numberOfAgents"));

        }

        try {

            clusterManager.startCluster(clusterName, numberOfMonitors, numberOfAgents);

        } catch (TimeoutException e) {

            e.printStackTrace();

            throw new ResourceException(Status.SERVER_ERROR_GATEWAY_TIMEOUT, e);

        } catch (Exception e) {

            e.printStackTrace();

            throw new ResourceException(Status.SERVER_ERROR_INTERNAL, e);

        }

    }

    @Override

    protected void describeGet(MethodInfo info) {

        super.describeGet(info);

        info.setDocumentation("Describe all Elastic Grid clusters.");

        info.getResponse().setDocumentation("The clusters.");

        RepresentationInfo representation = new RepresentationInfo();

        representation.setDocumentation("This representation exposes all running Elastic Grid Clusters.");

        representation.getDocumentations().get(0).setTitle("clusters");

        representation.setMediaType(MediaType.APPLICATION_XML);

        representation.getDocumentations().addAll(Arrays.asList(

                new DocumentationInfo("Example of output:<pre><![CDATA[" +

                        "<clusters xmlns=\"urn:elastic-grid:eg\">\n" +

                        "  <cluster name=\"cluster1\">\n" +

                        "    <node profile=\"monitor\">ec2-75...</node>\n" +

                        "    <node profile=\"monitor\">ec2-77...</node>\n" +

                        "    <node profile=\"agent\">ec2-37...</node>\n" +

                        "  </cluster>\n" +

                        "  <cluster name=\"cluster2\">\n" +

                        "    <node profile=\"monitor\">ec2-57...</node>\n" +

                        "    <node profile=\"monitor\">ec2-63...</node>\n" +

                        "    <node profile=\"agent\">ec2-31...</node>\n" +

                        "  </cluster>\n" +

                        "</clusters>" +

                        "]]></pre>")

        ));

        representation.setXmlElement("eg:clusters");

        info.getResponse().setRepresentations(Arrays.asList(representation));

    }

    @Override

    protected void describePost(MethodInfo info) {

        super.describePost(info);

        info.setDocumentation("Start a new Elastic Grid Cluster.");

        info.getRequest().setDocumentation("The cluster to start.");

        RepresentationInfo xmlRepresentation = new RepresentationInfo();

        xmlRepresentation.setDocumentation("This representation exposes a provisioning request for starting a new Elastic Grid Cluster.");

        xmlRepresentation.getDocumentations().get(0).setTitle("cluster-provisioning");

        xmlRepresentation.setMediaType(MediaType.APPLICATION_XML);

        xmlRepresentation.getDocumentations().addAll(Arrays.asList(

                new DocumentationInfo("Example of input:<pre><![CDATA[" +

                        "<cluster-provisioning name=\"my-cluster\" xmlns=\"urn:elastic-grid:eg\">\n" +

                        "\t<!-- Start 2 monitors -->\n" +

                        "\t<monitors>2</monitors>\n" +

                        "\t<!-- Start 3 agents -->\n" +

                        "\t<agents>3</agents>\n" +

                        "</cluster-provisioning>" +

                        "]]></pre>")

        ));

        xmlRepresentation.setXmlElement("eg:cluster-provisioning");

        RepresentationInfo formRepresentation = new RepresentationInfo();

        formRepresentation.setDocumentation("This representation exposes a provisioning request for starting a new Elastic Grid Cluster.");

        formRepresentation.getDocumentations().get(0).setTitle("cluster-provisioning");

        formRepresentation.setMediaType(MediaType.APPLICATION_WWW_FORM);

        formRepresentation.setParameters(Arrays.asList(

                new ParameterInfo("clusterName", true, "xs:string", ParameterStyle.PLAIN,

                        "The name of the Elastic Grid Cluster to start."),

                new ParameterInfo("numberOfMonitors", true, "xs:integer", ParameterStyle.PLAIN,

                        "The number of monitors to start in the cluster."),

                new ParameterInfo("numberOfAgents", true, "xs:integer", ParameterStyle.PLAIN,

                        "The number of agents to start in the cluster.")

        ));

        info.getRequest().setRepresentations(Arrays.asList(xmlRepresentation, formRepresentation));

    }

    @Override

    public boolean allowDelete() {

        return false;

    }

    @Override

    public boolean allowPut() {

        return false;

    }

}