io.seldon.external.ExternalPluginServer.java Source code

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Here is the source code for io.seldon.external.ExternalPluginServer.java

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/*
 * 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.APIException;
import io.seldon.api.state.GlobalConfigHandler;
import io.seldon.api.state.GlobalConfigUpdateListener;
import io.seldon.clustering.recommender.RecommendationContext.OptionsHolder;
import io.seldon.external.ExternalPredictionServer.PredictionServerConfig;
import io.seldon.plugins.PluginService;

import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;

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.codehaus.jackson.JsonFactory;
import org.codehaus.jackson.JsonNode;
import org.codehaus.jackson.JsonParser;
import org.codehaus.jackson.map.ObjectMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

@Component
public class ExternalPluginServer implements GlobalConfigUpdateListener, PluginService {

    private static Logger logger = Logger.getLogger(ExternalPluginServer.class.getName());
    private static final String name = ExternalPluginServer.class.getName();
    private static final String URL_PROPERTY_NAME = "io.seldon.algorithm.external.url";
    private static final String ZK_CONFIG_TEMP = "plugin_server";
    private PoolingHttpClientConnectionManager cm;
    private CloseableHttpClient httpClient;

    ObjectMapper mapper = new ObjectMapper();

    public String getName() {
        return name;
    }

    public static class PluginServerConfig {
        public int maxConnections;
    }

    @Autowired
    public ExternalPluginServer(GlobalConfigHandler globalConfigHandler) {
        cm = new PoolingHttpClientConnectionManager();
        cm.setMaxTotal(150);
        cm.setDefaultMaxPerRoute(150);
        httpClient = HttpClients.custom().setConnectionManager(cm).build();
        globalConfigHandler.addSubscriber(ZK_CONFIG_TEMP, this);
    }

    @Override
    public void configUpdated(String configKey, String configValue) {
        if (configValue != null && configValue.length() > 0) {
            ObjectMapper mapper = new ObjectMapper();
            try {
                PredictionServerConfig config = mapper.readValue(configValue, PredictionServerConfig.class);
                cm = new PoolingHttpClientConnectionManager();
                cm.setMaxTotal(config.maxConnections);
                cm.setDefaultMaxPerRoute(config.maxConnections);
                httpClient = HttpClients.custom().setConnectionManager(cm).build();
                logger.info("Updated httpclient to use " + config.maxConnections + " max connections");
            } catch (Exception e) {
                throw new RuntimeException(String.format("* Error * parsing statsd configValue[%s]", configValue),
                        e);
            }
        }

    }

    @Override
    public JsonNode execute(JsonNode payload, OptionsHolder options) {
        long timeNow = System.currentTimeMillis();
        URI uri = URI.create(options.getStringOption(URL_PROPERTY_NAME));
        try {
            URIBuilder builder = new URIBuilder().setScheme("http").setHost(uri.getHost()).setPort(uri.getPort())
                    .setPath(uri.getPath()).setParameter("json", payload.toString());

            uri = builder.build();
        } catch (URISyntaxException e) {
            throw new APIException(APIException.GENERIC_ERROR);
        }
        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);
            if (resp.getStatusLine().getStatusCode() == 200) {

                JsonFactory factory = mapper.getJsonFactory();
                JsonParser parser = factory.createJsonParser(resp.getEntity().getContent());
                JsonNode actualObj = mapper.readTree(parser);
                if (logger.isDebugEnabled())
                    logger.debug(
                            "External prediction server took " + (System.currentTimeMillis() - timeNow) + "ms");
                return actualObj;
            } else {
                logger.error(
                        "Couldn't retrieve prediction from external prediction server -- bad http return code: "
                                + resp.getStatusLine().getStatusCode());
                throw new APIException(APIException.GENERIC_ERROR);
            }
        } catch (IOException e) {
            logger.error("Couldn't retrieve prediction from external prediction server - ", e);
            throw new APIException(APIException.GENERIC_ERROR);
        }

    }
}