co.cask.cdap.gateway.handlers.VersionHandler.java Source code

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Here is the source code for co.cask.cdap.gateway.handlers.VersionHandler.java

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/*
 * Copyright  2014 Cask Data, Inc.
 *
 * Licensed 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 co.cask.cdap.gateway.handlers;

import co.cask.cdap.common.conf.Constants;
import co.cask.cdap.proto.Version;
import co.cask.http.AbstractHttpHandler;
import co.cask.http.HttpResponder;
import com.google.common.base.Charsets;
import com.google.common.io.Resources;
import org.jboss.netty.handler.codec.http.HttpRequest;
import org.jboss.netty.handler.codec.http.HttpResponseStatus;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;
import javax.ws.rs.GET;
import javax.ws.rs.Path;

/**
 * Handles version requests.
 */
public class VersionHandler extends AbstractHttpHandler {

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

    private final String version;

    public VersionHandler() {
        this.version = determineVersion();
    }

    @Path(Constants.Gateway.API_VERSION_3 + "/version")
    @GET
    public void version(@SuppressWarnings("UnusedParameters") HttpRequest request, HttpResponder responder) {
        responder.sendJson(HttpResponseStatus.OK, new Version(version));
    }

    private String determineVersion() {
        try {
            String version = Resources.toString(Resources.getResource("VERSION"), Charsets.UTF_8);
            if (!version.equals("${project.version}")) {
                return version.trim();
            }
        } catch (IOException e) {
            LOG.warn("Failed to determine current version", e);
        }
        return "unknown";
    }
}