Java tutorial
/** * Copyright (c) Codice Foundation * <p/> * This is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser * General Public License as published by the Free Software Foundation, either version 3 of the * License, or any later version. * <p/> * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without * even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. A copy of the GNU Lesser General Public License * is distributed along with this program and can be found at * <http://www.gnu.org/licenses/lgpl.html>. **/ package org.codice.ddf.catalog.twitter.source; import java.io.IOException; import java.io.Serializable; import java.net.URI; import java.net.URISyntaxException; import java.util.ArrayList; import java.util.Calendar; import java.util.Collections; import java.util.List; import java.util.Map; import java.util.Set; import java.util.stream.Collectors; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import ddf.catalog.data.ContentType; import ddf.catalog.data.Metacard; import ddf.catalog.data.Result; import ddf.catalog.data.impl.MetacardImpl; import ddf.catalog.data.impl.ResultImpl; import ddf.catalog.operation.QueryRequest; import ddf.catalog.operation.ResourceResponse; import ddf.catalog.operation.SourceResponse; import ddf.catalog.operation.impl.SourceResponseImpl; import ddf.catalog.resource.ResourceNotFoundException; import ddf.catalog.resource.ResourceNotSupportedException; import ddf.catalog.resource.ResourceReader; import ddf.catalog.source.FederatedSource; import ddf.catalog.source.SourceMonitor; import ddf.catalog.source.UnsupportedQueryException; import twitter4j.GeoLocation; import twitter4j.Query; import twitter4j.QueryResult; import twitter4j.Status; import twitter4j.Twitter; import twitter4j.TwitterException; import twitter4j.TwitterFactory; import twitter4j.conf.Configuration; import twitter4j.conf.ConfigurationBuilder; public class TwitterSource implements FederatedSource { private static final Logger LOGGER = LoggerFactory.getLogger(TwitterSource.class); TwitterFactory twitterFactory; String id; ResourceReader resourceReader; String consumerKey; String consumerSecret; public TwitterSource() { } public void init() { ConfigurationBuilder configurationBuilder = new ConfigurationBuilder(); Configuration configuration = configurationBuilder.setOAuthConsumerKey(consumerKey) .setOAuthConsumerSecret(consumerSecret).setApplicationOnlyAuthEnabled(true).build(); twitterFactory = new TwitterFactory(configuration); } public void destroy() { twitterFactory = null; } @Override public ResourceResponse retrieveResource(URI uri, Map<String, Serializable> arguments) throws IOException, ResourceNotFoundException, ResourceNotSupportedException { return resourceReader.retrieveResource(uri, arguments); } @Override public Set<String> getSupportedSchemes() { return Collections.emptySet(); } @Override public Set<String> getOptions(Metacard metacard) { return Collections.emptySet(); } @Override public boolean isAvailable() { Twitter instance = twitterFactory.getInstance(); try { instance.getOAuth2Token(); return true; } catch (TwitterException e) { LOGGER.error("Unable to get OAuth2 token.", e); return false; } } @Override public boolean isAvailable(SourceMonitor callback) { if (isAvailable()) { callback.setAvailable(); return true; } else { callback.setUnavailable(); return false; } } @Override public SourceResponse query(QueryRequest request) throws UnsupportedQueryException { Twitter instance = twitterFactory.getInstance(); try { instance.getOAuth2Token(); } catch (TwitterException e) { throw new UnsupportedQueryException("Unable to get OAuth2 token.", e); } TwitterFilterVisitor visitor = new TwitterFilterVisitor(); request.getQuery().accept(visitor, null); Query query = new Query(); query.setCount(request.getQuery().getPageSize()); if (visitor.hasSpatial()) { GeoLocation geoLocation = new GeoLocation(visitor.getLatitude(), visitor.getLongitude()); query.setGeoCode(geoLocation, visitor.getRadius(), Query.Unit.km); } if (visitor.getContextualSearch() != null) { query.setQuery(visitor.getContextualSearch().getSearchPhrase()); } if (visitor.getTemporalSearch() != null) { Calendar.Builder builder = new Calendar.Builder(); builder.setInstant(visitor.getTemporalSearch().getStartDate()); Calendar calendar = builder.build(); query.setSince(calendar.get(Calendar.YEAR) + "-" + calendar.get(Calendar.MONTH) + "-" + calendar.get(Calendar.DAY_OF_MONTH)); builder = new Calendar.Builder(); builder.setInstant(visitor.getTemporalSearch().getEndDate()); calendar = builder.build(); query.setUntil(calendar.get(Calendar.YEAR) + "-" + calendar.get(Calendar.MONTH) + "-" + calendar.get(Calendar.DAY_OF_MONTH)); } QueryResult queryResult; try { queryResult = instance.search().search(query); } catch (TwitterException e) { throw new UnsupportedQueryException(e); } List<Result> resultList = new ArrayList<>(queryResult.getCount()); resultList.addAll(queryResult.getTweets().stream().map(status -> new ResultImpl(getMetacard(status))) .collect(Collectors.toList())); return new SourceResponseImpl(request, resultList); } private Metacard getMetacard(Status status) { MetacardImpl metacard = new MetacardImpl(); metacard.setSourceId(id); metacard.setId(String.valueOf(status.getId())); metacard.setTitle(status.getText()); metacard.setMetadata("<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>" + "<Resource>" + "<name>" + status.getText() + "</name>" + "</Resource>"); metacard.setCreatedDate(status.getCreatedAt()); metacard.setModifiedDate(status.getCreatedAt()); metacard.setEffectiveDate(status.getCreatedAt()); metacard.setPointOfContact(status.getUser().getName()); if (status.getURLEntities() != null && status.getURLEntities().length > 0) { try { metacard.setResourceURI(new URI(status.getURLEntities()[0].getExpandedURL())); } catch (URISyntaxException e) { LOGGER.error("Unable to set resource URI.", e); } } else if (status.getMediaEntities() != null && status.getMediaEntities().length > 0) { try { metacard.setResourceURI(new URI(status.getMediaEntities()[0].getExpandedURL())); } catch (URISyntaxException e) { LOGGER.error("Unable to set resource URI.", e); } } else if (status.getExtendedMediaEntities() != null && status.getExtendedMediaEntities().length > 0) { try { metacard.setResourceURI(new URI(status.getExtendedMediaEntities()[0].getExpandedURL())); } catch (URISyntaxException e) { LOGGER.error("Unable to set resource URI.", e); } } GeoLocation geoLocation = status.getGeoLocation(); if (geoLocation != null) { metacard.setLocation("POINT (" + geoLocation.getLongitude() + " " + geoLocation.getLatitude() + ")"); } return metacard; } @Override public Set<ContentType> getContentTypes() { return Collections.emptySet(); } @Override public String getVersion() { return "1"; } @Override public String getId() { return id; } public void setId(String id) { this.id = id; } @Override public String getTitle() { return "Twitter Federated Source"; } @Override public String getDescription() { return "Query using the Twitter API."; } @Override public String getOrganization() { return "Codice"; } public String getConsumerKey() { return consumerKey; } public void setConsumerKey(String consumerKey) { this.consumerKey = consumerKey; } public String getConsumerSecret() { return consumerSecret; } public void setConsumerSecret(String consumerSecret) { this.consumerSecret = consumerSecret; } public void setResourceReader(ResourceReader resourceReader) { this.resourceReader = resourceReader; } }