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();
	}
}