SystemsRequest.java

/**
 * Copyright (c) 2010-2016 by the respective copyright holders.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 */
package org.openhab.binding.enphaseenergy.internal.messages;

import static org.apache.commons.httpclient.util.URIUtil.encodeQuery;
import static org.openhab.io.net.http.HttpUtil.executeUrl;

import java.util.Properties;

import org.apache.commons.httpclient.URIException;
import org.apache.commons.lang.builder.ToStringBuilder;
import org.codehaus.jackson.map.JsonMappingException;
import org.codehaus.jackson.map.ObjectMapper;
import org.openhab.binding.enphaseenergy.internal.EnphaseenergyException;

/**
 * A devicelist request returns the list of systems controlled by the user, and their
 * modules.
 *
 * @author Markus Fritze
 * @since 1.7.0
 * @see <a href="https://developer.enphase.com/docs#api-systems">systems</a>
 */
public class SystemsRequest extends AbstractMessage {

    protected static final String HTTP_GET = "GET";

    protected static final String API_BASE_URL = "https://api.enphaseenergy.com/api/v2/";

    protected static final String RESOURCE_URL = API_BASE_URL + "systems";

    protected static final Properties HTTP_HEADERS;

    protected static final int HTTP_REQUEST_TIMEOUT = 10000;

    protected static final ObjectMapper JSON = new ObjectMapper();

    static {
        HTTP_HEADERS = new Properties();
        HTTP_HEADERS.put("Accept", "application/json");
    }

    protected final RuntimeException newException(final String message, final Exception cause, final String url,
            final String json) {
        if (cause instanceof JsonMappingException) {
            return new EnphaseenergyException("Could not parse JSON from URL '" + url + "': " + json, cause);
        }

        return new EnphaseenergyException(message, cause);
    }

    private final String key;
    private final String user_id;
    private final Integer system_id;

    /**
     * Creates a request for the list of devices owned by the user
     * 
     * @param key
     *            mandatory, must not be <code>null</code>
     * @param user_id
     *            mandatory, must not be <code>null</code>
     */
    public SystemsRequest(final String key, final String user_id, final Integer system_id) {
        assert key != null : "key must not be null!";
        assert user_id != null : "user_id must not be null!";
        assert system_id != null : "system_id must not be null!";

        this.key = key;
        this.user_id = user_id;
        this.system_id = system_id;
    }

    public SystemsResponse execute() {
        final String url = prepare();
        String json = null;

        try {
            json = executeQuery(url);

            final SystemsResponse response = JSON.readValue(json, SystemsResponse.class);
            return response;
        } catch (final Exception e) {
            throw newException("Could not execute system summary request!", e, url, json);
        }
    }

    @Override
    public String toString() {
        final ToStringBuilder builder = createToStringBuilder();
        builder.appendSuper(super.toString());
        builder.append("key", this.key);
        builder.append("user_id", this.user_id);
        builder.append("system_id", this.system_id);
        return builder.toString();
    }

    protected String executeQuery(final String url) {
        return executeUrl(HTTP_GET, url, HTTP_HEADERS, null, null, HTTP_REQUEST_TIMEOUT);
    }

    public String prepare() {
        final StringBuilder urlBuilder = new StringBuilder(RESOURCE_URL);
        urlBuilder.append("/");
        urlBuilder.append(this.system_id);
        urlBuilder.append("/summary");
        urlBuilder.append("?key=");
        urlBuilder.append(this.key);
        urlBuilder.append("&user_id=");
        urlBuilder.append(this.user_id);

        try {
            return encodeQuery(urlBuilder.toString());
        } catch (final URIException e) {
            throw new EnphaseenergyException("Could not prepare systems request!", e);
        }
    }
}