/*
* Seldon -- open source prediction engine
* =======================================
*
* Copyright 2011-2015 Seldon Technologies Ltd and Rummble Ltd (http://www.seldon.io/)
*
* ********************************************************************************************
*
* 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 io.seldon.external;
import io.seldon.api.Constants;
import io.seldon.api.resource.ConsumerBean;
import io.seldon.api.resource.service.ItemService;
import io.seldon.clustering.recommender.ItemRecommendationAlgorithm;
import io.seldon.clustering.recommender.ItemRecommendationResultSet;
import io.seldon.clustering.recommender.RecommendationContext;
import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.apache.commons.collections.CollectionUtils;
import org.apache.commons.lang3.StringUtils;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.protocol.HttpClientContext;
import org.apache.http.client.utils.URIBuilder;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
import org.apache.http.protocol.HttpContext;
import org.apache.log4j.Logger;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.ObjectReader;
/**
* An Item Recommendation Algorithm that calls out to an HTTP endpoint for its recs.
*
* @author firemanphil
* Date: 26/03/15
* Time: 12:15
*/
@Component
public class ExternalItemRecommendationAlgorithm implements ItemRecommendationAlgorithm {
private static Logger logger = Logger.getLogger(ExternalItemRecommendationAlgorithm.class.getName());
private static final String URL_PROPERTY_NAME="io.seldon.algorithm.external.url";
private static final String ALG_NAME_PROPERTY_NAME ="io.seldon.algorithm.external.name";
private final PoolingHttpClientConnectionManager cm;
private final CloseableHttpClient httpClient;
ObjectMapper mapper = new ObjectMapper();
private static final int DEFAULT_REQ_TIMEOUT = 200;
private static final int DEFAULT_CON_TIMEOUT = 500;
private static final int DEFAULT_SOCKET_TIMEOUT = 2000;
ItemService itemService;
@Autowired
public ExternalItemRecommendationAlgorithm(ItemService itemService){
cm = new PoolingHttpClientConnectionManager();
cm.setMaxTotal(100);
cm.setDefaultMaxPerRoute(20);
RequestConfig requestConfig = RequestConfig.custom()
.setConnectionRequestTimeout(DEFAULT_REQ_TIMEOUT)
.setConnectTimeout(DEFAULT_CON_TIMEOUT)
.setSocketTimeout(DEFAULT_SOCKET_TIMEOUT).build();
httpClient = HttpClients.custom()
.setConnectionManager(cm)
.setDefaultRequestConfig(requestConfig)
.build();
this.itemService = itemService;
}
@Override
public ItemRecommendationResultSet recommend(String client, Long user, Set<Integer> dimensions, int maxRecsCount,
RecommendationContext ctxt, List<Long> recentItemInteractions) {
long timeNow = System.currentTimeMillis();
String recommenderName = ctxt.getOptsHolder().getStringOption(ALG_NAME_PROPERTY_NAME);
String baseUrl = ctxt.getOptsHolder().getStringOption(URL_PROPERTY_NAME);
if (ctxt.getInclusionKeys().isEmpty()){
logger.warn("Cannot get external recommendations are no includers were used. Returning 0 results");
return new ItemRecommendationResultSet(recommenderName);
}
URI uri = URI.create(baseUrl);
try {
URIBuilder builder = new URIBuilder().setScheme("http")
.setHost(uri.getHost())
.setPort(uri.getPort())
.setPath(uri.getPath())
.setParameter("client", client)
.setParameter("user_id", user.toString())
.setParameter("recent_interactions",StringUtils.join(recentItemInteractions,","))
.setParameter("dimensions", StringUtils.join(dimensions, ","))
.setParameter("exclusion_items", StringUtils.join(ctxt.getExclusionItems(),","))
.setParameter("data_key", StringUtils.join(ctxt.getInclusionKeys(),","))
.setParameter("limit", String.valueOf(maxRecsCount));
if (ctxt.getCurrentItem() != null)
builder.setParameter("item_id", ctxt.getCurrentItem().toString());
uri = builder.build();
} catch (URISyntaxException e) {
logger.error("Couldn't create URI for external recommender with name " + recommenderName, e);
return new ItemRecommendationResultSet(recommenderName);
}
HttpContext context = HttpClientContext.create();
HttpGet httpGet = new HttpGet(uri);
try {
if (logger.isDebugEnabled())
logger.debug("Requesting " + httpGet.getURI().toString());
CloseableHttpResponse resp = httpClient.execute(httpGet, context);
try
{
if(resp.getStatusLine().getStatusCode() == 200)
{
ConsumerBean c = new ConsumerBean(client);
ObjectReader reader = mapper.reader(AlgsResult.class);
AlgsResult recs = reader.readValue(resp.getEntity().getContent());
List<ItemRecommendationResultSet.ItemRecommendationResult> results = new ArrayList<>(recs.recommended.size());
for (AlgResult rec : recs.recommended) {
Map<String,Integer> attrDimsCandidate = itemService.getDimensionIdsForItem(c, rec.item);
if (CollectionUtils.containsAny(dimensions, attrDimsCandidate.values()) || dimensions.contains(Constants.DEFAULT_DIMENSION))
{
if (logger.isDebugEnabled())
logger.debug("Adding item "+rec.item);
results.add(new ItemRecommendationResultSet.ItemRecommendationResult(rec.item, rec.score));
}
else
{
if (logger.isDebugEnabled())
logger.debug("Rejecting item "+rec.item+" as not in dimensions "+dimensions);
}
}
if (logger.isDebugEnabled())
logger.debug("External recommender took "+(System.currentTimeMillis()-timeNow) + "ms");
return new ItemRecommendationResultSet(results,recommenderName);
} else {
logger.error("Couldn't retrieve recommendations from external recommender -- bad http return code: " + resp.getStatusLine().getStatusCode());
}
}
finally
{
if (resp != null)
resp.close();
}
} catch (IOException e) {
logger.error("Couldn't retrieve recommendations from external recommender - ", e);
}
catch (Exception e)
{
logger.error("Couldn't retrieve recommendations from external recommender - ", e);
}
return new ItemRecommendationResultSet(recommenderName);
}
@Override
public String name() {
return null;
}
public static class AlgsResult {
public List<AlgResult> recommended;
}
public static class AlgResult {
public Long item;
public Float score;
}
}