com.meltmedia.dropwizard.etcd.json.EtcdWatchServiceRule.java Source code

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Here is the source code for com.meltmedia.dropwizard.etcd.json.EtcdWatchServiceRule.java

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/**
 * Copyright (C) 2015 meltmedia (christian.trimble@meltmedia.com)
 *
 * 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 com.meltmedia.dropwizard.etcd.json;

import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;
import java.util.function.Supplier;

import mousio.etcd4j.EtcdClient;

import org.junit.rules.TestRule;
import org.junit.runner.Description;
import org.junit.runners.model.Statement;

import com.codahale.metrics.MetricRegistry;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.meltmedia.dropwizard.etcd.json.WatchService;

public class EtcdWatchServiceRule implements TestRule {

    private Supplier<EtcdClient> clientSupplier;
    private String directory;
    private WatchService service;

    public EtcdWatchServiceRule(Supplier<EtcdClient> clientSupplier, String directory) {
        this.clientSupplier = clientSupplier;
        this.directory = directory;
    }

    @Override
    public Statement apply(Statement base, Description description) {
        return new Statement() {
            @Override
            public void evaluate() throws Throwable {
                ScheduledExecutorService executor = Executors.newSingleThreadScheduledExecutor();
                ObjectMapper mapper = new ObjectMapper();

                try {
                    try {
                        clientSupplier.get().deleteDir(directory).recursive().send().get();
                    } catch (Exception e) {
                        System.out.printf("could not delete %s from service rule", directory);
                        e.printStackTrace();
                    }

                    service = WatchService.builder().withEtcdClient(clientSupplier).withDirectory(directory)
                            .withExecutor(executor).withMapper(mapper).withMetricRegistry(new MetricRegistry())
                            .withWatchTimeout(10, TimeUnit.MILLISECONDS).build();

                    service.start();

                    try {

                        base.evaluate();
                    } finally {
                        try {
                            service.stop();
                        } catch (Throwable ioe) {
                            ioe.printStackTrace(System.err);
                        }
                        service = null;
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                    throw e;
                } finally {
                    executor.shutdown();
                }

            }
        };
    }

    public WatchService getService() {
        return service;
    }

}