TileTranslationServiceImpl.java

/*
 * Copyright (c) 2015 Uncharted Software
 * https://uncharted.software/
 *
 * Released under the MIT License.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
 * of the Software, and to permit persons to whom the Software is furnished to do
 * so, subject to the following conditions:

 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
package com.oculusinfo.tile.rest.translation;


import com.google.inject.Inject;
import com.google.inject.Singleton;
import com.oculusinfo.tile.rest.config.ConfigException;
import com.oculusinfo.tile.rest.config.ConfigPropertiesService;
import org.apache.commons.lang.StringUtils;
import org.json.JSONException;
import org.json.JSONObject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.net.ssl.HttpsURLConnection;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;
import java.util.Properties;



/**
 * A service that will translate given text to a target language based on the parameters
 * 	passed in.  Currently only supports the Google Translate Service.
 *
 */
@Singleton
public class TileTranslationServiceImpl implements TileTranslationService {

	private static final Logger LOGGER = LoggerFactory.getLogger(TileTranslationServiceImpl.class);

	public static final String TRANSLATE_API_KEY = "translation.api.key";
	public static final String TRANSLATE_API_ENDPOINT = "translation.api.endpoint";

	private ConfigPropertiesService _service;

	@Inject
	public TileTranslationServiceImpl( ConfigPropertiesService service ) {
		this._service = service;
	}

    /* (non-Javadoc)
	 * @see TileUtilsServiceImpl#getTranslationGoogle(JSONObject query)
	 */
	public JSONObject getTranslation( JSONObject query ) {
		JSONObject result = null;
    	try {
    		// get the translation arguments from the query
    		String service = query.getString("service");
    		String text = query.getString("text");
        	String target = query.getString("target");
			String source = null;
			if (query.has("source")) {
				source = query.getString("source");
			}

    		// as we integrate more translation service we can add a more sophisticated selection mechanism
        	if ( StringUtils.equalsIgnoreCase( service, "google" ) ) {
            	Properties properties = _service.getConfigProperties();
            	if ( properties != null ) {
	        		String translationApiKey = properties.getProperty(TRANSLATE_API_KEY);
	        		String translationApiEndpoint = properties.getProperty(TRANSLATE_API_ENDPOINT);

	        		if ( translationApiKey != null && translationApiEndpoint != null ) {
						result = translateGoogle( text, source, target, translationApiKey, translationApiEndpoint);
	        		}
            	}
            }
        	if ( result == null ){
            	JSONObject resultErr = new JSONObject();
            	resultErr.put("message", "Incorrect Translation Service Configuration");

            	result = new JSONObject();
            	result.put("error", resultErr);
            }
    	} catch ( JSONException e ) {
    		LOGGER.error( "Incorrect Configuration for Translation API", e );
		} catch ( ConfigException e ) {
			LOGGER.error( "Error with internal configuration properties", e );
		}
		return result;
	}

	private JSONObject translateGoogle(String text,  String sourceLang, String targetLang, String key, String endpoint) {
		JSONObject result = null;
		String srcParam = sourceLang != null ? "&source=" + sourceLang : "";
		try {
			String urlStr = endpoint + "?key=" + key + "&q=" + text + "&target=" + targetLang + srcParam;
			URL url = new URL( urlStr );

			HttpsURLConnection connection = (HttpsURLConnection)url.openConnection();
			InputStream stream;
			if ( connection.getResponseCode() == 200 ) //success
			{
				stream = connection.getInputStream();
			} else {
				stream = connection.getErrorStream();
			}
			BufferedReader reader = new BufferedReader(new InputStreamReader( stream, "UTF-8" ) );
			StringBuilder reply = new StringBuilder();
			String line;
			while (( line = reader.readLine() ) != null ) {
				reply.append(line);
			}
			result = new JSONObject( reply.toString() );
		} catch ( IOException e ) {
			LOGGER.error( "Error reading response from Google Translation Service", e );
		} catch (JSONException e) {
			LOGGER.error( "Error creating JSON Objects from Google Translation Service response", e );
		}

		return result;
	}
}