org.avidj.zuul.client.ZuulRestClient.java Source code

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Here is the source code for org.avidj.zuul.client.ZuulRestClient.java

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package org.avidj.zuul.client;

/*
 * #%L
 * zuul-client
 * %%
 * Copyright (C) 2015 David Kensche
 * %%
 * 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.
 * #L%
 */

import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableMap;

import org.avidj.zuul.core.Lock;
import org.avidj.zuul.core.LockManager;
import org.avidj.zuul.core.LockScope;
import org.avidj.zuul.core.LockType;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.HttpEntity;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpMethod;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.web.client.RestTemplate;
import org.springframework.web.util.UriComponentsBuilder;

import java.net.MalformedURLException;
import java.net.URL;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;

public class ZuulRestClient implements LockManager {
    private static final Logger LOG = LoggerFactory.getLogger(ZuulRestClient.class);
    private static final Map<LockScope, String> SCOPE_TO_PARAM = ImmutableMap.of(LockScope.DEEP, "d",
            LockScope.SHALLOW, "s");
    private static final Map<LockType, String> TYPE_TO_PARAM = ImmutableMap.of(LockType.READ, "r", LockType.WRITE,
            "w");
    private final String serviceUrl;

    /**
     * Create a new REST client for Zuul.
     * @param serviceUrl the URL for accessing the Zuul lock service. 
     */
    public ZuulRestClient(String serviceUrl) {
        Preconditions.checkNotNull(serviceUrl);
        checkIsUrl(serviceUrl);
        if (!serviceUrl.endsWith("/")) {
            serviceUrl += "/";
        }
        this.serviceUrl = serviceUrl;
    }

    @Override
    public void setSessionTimeout(long timeoutMillis) {
        throw new UnsupportedOperationException("not yet implemented");
    }

    @Override
    public Set<Lock> getLocks(String session) {
        throw new UnsupportedOperationException("not yet implemented");
    }

    @Override
    public boolean readLock(String session, List<String> path, LockScope scope) {
        throw new UnsupportedOperationException("not yet implemented");
    }

    @Override
    public boolean writeLock(String session, List<String> path, LockScope scope) {
        throw new UnsupportedOperationException("not yet implemented");
    }

    @Override
    public boolean lock(String sessionId, List<String> path, LockType type, LockScope scope) {
        RestTemplate restTemplate = new RestTemplate();

        HttpHeaders headers = new HttpHeaders();
        headers.setAccept(Arrays.asList(MediaType.APPLICATION_JSON));
        HttpEntity<String> entity = new HttpEntity<String>("parameters", headers);

        Map<String, String> parameters = new HashMap<>();
        parameters.put("id", sessionId); // set the session id
        UriComponentsBuilder uriBuilder = UriComponentsBuilder.fromHttpUrl(serviceUrl + lockPath(path))
                .queryParam("t", type(type)).queryParam("s", scope(scope));

        ResponseEntity<String> result = restTemplate.exchange(uriBuilder.build().encode().toUri(), HttpMethod.PUT,
                entity, String.class);

        LOG.info(result.toString());
        HttpStatus code = result.getStatusCode();
        return code.equals(HttpStatus.CREATED);
    }

    private static String scope(LockScope scope) {
        String result = SCOPE_TO_PARAM.get(scope);
        if (result == null) {
            throw new IllegalArgumentException("unknown lock scope: " + scope);
        }
        return result;
    }

    private static String type(LockType type) {
        String result = TYPE_TO_PARAM.get(type);
        if (result == null) {
            throw new IllegalArgumentException("unknown lock type: " + type);
        }
        return result;
    }

    @Override
    public boolean multiLock(String sessionId, List<List<String>> paths, LockType type, LockScope scope) {
        throw new UnsupportedOperationException("not yet implemented");
    }

    @Override
    public boolean release(String session, List<String> path) throws IllegalStateException {
        throw new UnsupportedOperationException("not yet implemented");
    }

    @Override
    public int release(String session, Collection<List<String>> paths) {
        throw new UnsupportedOperationException("not yet implemented");
    }

    @Override
    public void release(String session) {
        throw new UnsupportedOperationException("not yet implemented");
    }

    @Override
    public boolean upScope(String session, List<String> path, LockType type) {
        throw new UnsupportedOperationException("not yet implemented");
    }

    @Override
    public boolean downScope(String session, List<String> path, LockType type, LockScope shallow) {
        throw new UnsupportedOperationException("not yet implemented");
    }

    @Override
    public void heartbeat(String session) {
        throw new UnsupportedOperationException("not yet implemented");
    }

    private static String lockPath(List<String> path) {
        if (path.isEmpty()) {
            return "";
        }
        StringBuilder string = new StringBuilder(path.get(0));
        for (int i = 1, n = path.size(); i < n; i++) {
            string.append("/").append(path.get(i));
        }
        return string.toString();
    }

    private static void checkIsUrl(String serviceUrl) {
        try {
            new URL(serviceUrl);
        } catch (MalformedURLException e) {
            throw new IllegalArgumentException("Not a valid URL.", e);
        }
    }
}