ComputeServer.java

package org.drip.service.engine;

/*
 * -*- mode: java; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 */

/*!
 * Copyright (C) 2020 Lakshmi Krishnamurthy
 * Copyright (C) 2019 Lakshmi Krishnamurthy
 * Copyright (C) 2018 Lakshmi Krishnamurthy
 * Copyright (C) 2017 Lakshmi Krishnamurthy
 * Copyright (C) 2016 Lakshmi Krishnamurthy
 * 
 *  This file is part of DROP, an open-source library targeting analytics/risk, transaction cost analytics,
 *      asset liability management analytics, capital, exposure, and margin analytics, valuation adjustment
 *      analytics, and portfolio construction analytics within and across fixed income, credit, commodity,
 *      equity, FX, and structured products. It also includes auxiliary libraries for algorithm support,
 *      numerical analysis, numerical optimization, spline builder, model validation, statistical learning,
 *      and computational support.
 *  
 *      https://lakshmidrip.github.io/DROP/
 *  
 *  DROP is composed of three modules:
 *  
 *  - DROP Product Core - https://lakshmidrip.github.io/DROP-Product-Core/
 *  - DROP Portfolio Core - https://lakshmidrip.github.io/DROP-Portfolio-Core/
 *  - DROP Computational Core - https://lakshmidrip.github.io/DROP-Computational-Core/
 * 
 *  DROP Product Core implements libraries for the following:
 *  - Fixed Income Analytics
 *  - Loan Analytics
 *  - Transaction Cost Analytics
 * 
 *  DROP Portfolio Core implements libraries for the following:
 *  - Asset Allocation Analytics
 *  - Asset Liability Management Analytics
 *  - Capital Estimation Analytics
 *  - Exposure Analytics
 *  - Margin Analytics
 *  - XVA Analytics
 * 
 *  DROP Computational Core implements libraries for the following:
 *  - Algorithm Support
 *  - Computation Support
 *  - Function Analysis
 *  - Model Validation
 *  - Numerical Analysis
 *  - Numerical Optimizer
 *  - Spline Builder
 *  - Statistical Learning
 * 
 *  Documentation for DROP is Spread Over:
 * 
 *  - Main                     => https://lakshmidrip.github.io/DROP/
 *  - Wiki                     => https://github.com/lakshmiDRIP/DROP/wiki
 *  - GitHub                   => https://github.com/lakshmiDRIP/DROP
 *  - Repo Layout Taxonomy     => https://github.com/lakshmiDRIP/DROP/blob/master/Taxonomy.md
 *  - Javadoc                  => https://lakshmidrip.github.io/DROP/Javadoc/index.html
 *  - Technical Specifications => https://github.com/lakshmiDRIP/DROP/tree/master/Docs/Internal
 *  - Release Versions         => https://lakshmidrip.github.io/DROP/version.html
 *  - Community Credits        => https://lakshmidrip.github.io/DROP/credits.html
 *  - Issues Catalog           => https://github.com/lakshmiDRIP/DROP/issues
 *  - JUnit                    => https://lakshmidrip.github.io/DROP/junit/index.html
 *  - Jacoco                   => https://lakshmidrip.github.io/DROP/jacoco/index.html
 * 
 *  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.
 */

/**
 * <i>ComputeServer</i> contains the Functionality behind the DROP API Compute Service Engine.
 * 
 * <br><br>
 *  <ul>
 *      <li><b>Module </b> = <a href = "https://github.com/lakshmiDRIP/DROP/tree/master/ComputationalCore.md">Computational Core Module</a></li>
 *      <li><b>Library</b> = <a href = "https://github.com/lakshmiDRIP/DROP/tree/master/ComputationSupportLibrary.md">Computation Support</a></li>
 *      <li><b>Project</b> = <a href = "https://github.com/lakshmiDRIP/DROP/tree/master/src/main/java/org/drip/service/README.md">Environment, Product/Definition Containers, and Scenario/State Manipulation APIs</a></li>
 *      <li><b>Package</b> = <a href = "https://github.com/lakshmiDRIP/DROP/tree/master/src/main/java/org/drip/service/engine/README.md">Compute Engine Request-Response Thunker</a></li>
 *  </ul>
 * <br><br>
 *
 * @author Lakshmi Krishnamurthy
 */

public class ComputeServer {

    /**
     * The DRIP compute Service Engine Port
     */

    public static final int DRIP_COMPUTE_ENGINE_PORT = 9090;

    private int _iListenerPort = -1;
    private java.net.ServerSocket _socketListener = null;

    /**
     * Create a Standard Instance of the ComputeServer
     * 
     * @return The Standard ComputeServer Instance
     */

    public static final ComputeServer Standard()
    {
        try {
            ComputeServer cs = new ComputeServer (DRIP_COMPUTE_ENGINE_PORT);

            return cs.initialize() ? cs : null;
        } catch (java.lang.Exception e) {
            e.printStackTrace();
        }

        return null;
    }

    /**
     * ComputServer Constructor
     * 
     * @param iListenerPort The Listener Port
     * 
     * @throws java.lang.Exception Thrown if the Inputs are Invalid
     */

    public ComputeServer (
        final int iListenerPort)
        throws java.lang.Exception
    {
        if (0 >= (_iListenerPort = iListenerPort))
            throw new java.lang.Exception ("ComputeServer Constructor => Invalid Inputs");
    }

    /**
     * Initialize the Compute Server Engine Listener Setup
     * 
     * @return TRUE - The Compute Server Engine Listener Setup
     */

    public boolean initialize()
    {
        try {
            _socketListener = new java.net.ServerSocket (_iListenerPort);

            return true;
        } catch (java.lang.Exception e) {
            e.printStackTrace();
        }

        return false;
    }

    /**
     * Spin on the Listener Loop
     * 
     * @return FALSE - Spinning Terminated
     */

    public boolean spin()
    {
        while (true) {
            try {
                java.net.Socket s = _socketListener.accept();

                if (null == s) return false;

                java.lang.String strJSONRequest = new java.io.BufferedReader (new java.io.InputStreamReader
                    (s.getInputStream())).readLine();

                System.out.println (strJSONRequest);

                java.lang.Object objRequest = org.drip.json.simple.JSONValue.parse (strJSONRequest);

                if (null == objRequest || !(objRequest instanceof org.drip.json.simple.JSONObject))
                    return false;

                org.drip.json.simple.JSONObject jsonRequest = (org.drip.json.simple.JSONObject) objRequest;

                java.lang.Object objResponse = org.drip.json.simple.JSONValue.parse
                    (org.drip.service.json.KeyHoleSkeleton.Thunker (strJSONRequest));

                if (null == objResponse) return false;

                org.drip.json.simple.JSONObject jsonResponse = (org.drip.json.simple.JSONObject) objResponse;

                if (!org.drip.service.engine.RequestResponseDecorator.AffixResponseHeaders (jsonResponse,
                    jsonRequest))
                    return false;

                System.out.println ("\n\n" + jsonResponse.toJSONString());

                java.io.PrintWriter pw = new java.io.PrintWriter (s.getOutputStream(), true);

                pw.write (jsonResponse.toJSONString() + "\n");

                pw.flush();
            } catch (java.lang.Exception e) {
                e.printStackTrace();

                return false;
            }
        }
    }

    public static final void main (
        final java.lang.String[] astrArgs)
        throws java.lang.Exception
    {
        org.drip.service.env.EnvManager.InitEnv ("");

        ComputeServer cs = ComputeServer.Standard();

        cs.spin();
    }
}