com.boundary.sdk.event.esper.EsperRouteBuilder.java Source code

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Here is the source code for com.boundary.sdk.event.esper.EsperRouteBuilder.java

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// Copyright 2014-2015 Boundary, Inc.
//
// 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 com.boundary.sdk.event.esper;

import static org.apache.camel.LoggingLevel.DEBUG;

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

import org.apache.camel.Exchange;
import org.apache.camel.Message;
import org.apache.camel.Processor;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.boundary.sdk.event.BoundaryRouteBuilder;
import com.espertech.esper.client.EventBean;
import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper;

/**
 * Implementation of a Esper streaming route
 */
public class EsperRouteBuilder extends BoundaryRouteBuilder {

    private static Logger LOG = LoggerFactory.getLogger(EsperRouteBuilder.class);

    private String configuration;
    private String instance;
    private QueryList queryList;

    public EsperRouteBuilder() {
    }

    public String getConfiguration() {
        return configuration;
    }

    public void setConfiguration(String configuration) {
        this.configuration = configuration;
    }

    public String getInstance() {
        return instance;
    }

    public void setInstance(String instance) {
        this.instance = instance;
    }

    protected QueryList getQueryList() {
        return this.queryList;
    }

    private QueryList load(URI uri) {
        ObjectMapper mapper = new ObjectMapper();
        QueryList queryList = null;
        LOG.info("Loading queries from {}", uri);
        File file = new File(uri);

        try {
            queryList = mapper.readValue(file, QueryList.class);
        } catch (JsonParseException e) {
            e.printStackTrace();
        } catch (JsonMappingException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        return queryList;
    }

    /**
     * TODO: Proper handling of exception
     * @throws URISyntaxException {@link URISyntaxException}
     */
    protected void loadConfiguration() throws URISyntaxException {
        ClassLoader classLoader = this.getClass().getClassLoader();
        URL url = classLoader.getResource(this.configuration);
        this.queryList = load(url.toURI());
    }

    public void configure() throws Exception {
        String inputUri = String.format("esper://%s?configured=true", this.getInstance());

        from(this.getFromUri()).startupOrder(this.getStartUpOrder()).routeId(this.getRouteId() + "-INPUT")
                .unmarshal().serialization()
                .log(DEBUG, "headers: ${headers} body; ${body}, class: ${body.getClass.toString}").to(inputUri);

        addQueriesToRoute();
    }

    private void addQueriesToRoute() throws URISyntaxException {
        loadConfiguration();
        QueryList list = this.getQueryList();

        for (Query query : list.getQueries()) {
            if (query.isEnabled()) {
                addQuery(query.getName(), query.getQuery());
            }
        }
    }

    private void addQuery(String name, String query) {
        String queryUri = String.format("esper://%s?configured=true&eql=%s", this.getInstance(), query);
        this.startUpOrder++;

        LOG.info("Adding query \"{}\": \"{}\"", name, query);

        from(queryUri).startupOrder(this.getStartUpOrder())
                .routeId(String.format("%s-QUERY: %s", this.getRouteId(), name)).process(new Processor() {
                    public void process(Exchange exchange) throws Exception {
                        Message in = exchange.getIn();
                        EventBean event = in.getBody(EventBean.class);
                        Object e = event.getUnderlying();
                        in.setBody(e);
                    }
                }).log(DEBUG, "headers: ${headers} body; ${body}, class: ${body.getClass.toString}").marshal()
                .serialization().to(this.toUri);
    }
}