InitializationFilter.java

/**
 * This Source Code Form is subject to the terms of the Mozilla Public License,
 * v. 2.0. If a copy of the MPL was not distributed with this file, You can
 * obtain one at http://mozilla.org/MPL/2.0/. OpenMRS is also distributed under
 * the terms of the Healthcare Disclaimer located at http://openmrs.org/license.
 *
 * Copyright (C) OpenMRS Inc. OpenMRS is a registered trademark and the OpenMRS
 * graphic logo is a trademark of OpenMRS Inc.
 */
package org.openmrs.web.filter.initialization;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.net.URI;
import java.nio.charset.StandardCharsets;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.Base64;
import java.util.Base64.Encoder;
import java.util.HashMap;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.Properties;
import java.util.Random;
import java.util.zip.ZipInputStream;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import liquibase.changelog.ChangeSet;
import org.apache.commons.io.IOUtils;
import org.openmrs.ImplementationId;
import org.openmrs.api.APIAuthenticationException;
import org.openmrs.api.PasswordException;
import org.openmrs.api.UserService;
import org.openmrs.api.context.Context;
import org.openmrs.api.context.ContextAuthenticationException;
import org.openmrs.liquibase.ChangeLogDetective;
import org.openmrs.liquibase.ChangeLogVersionFinder;
import org.openmrs.module.MandatoryModuleException;
import org.openmrs.module.OpenmrsCoreModuleException;
import org.openmrs.module.web.WebModuleUtil;
import org.openmrs.util.DatabaseUpdateException;
import org.openmrs.util.DatabaseUpdater;
import org.openmrs.liquibase.ChangeSetExecutorCallback;
import org.openmrs.util.DatabaseUpdaterLiquibaseProvider;
import org.openmrs.util.DatabaseUtil;
import org.openmrs.util.InputRequiredException;
import org.openmrs.util.OpenmrsConstants;
import org.openmrs.util.OpenmrsUtil;
import org.openmrs.util.PrivilegeConstants;
import org.openmrs.util.Security;
import org.openmrs.web.Listener;
import org.openmrs.web.WebConstants;
import org.openmrs.web.WebDaemon;
import org.openmrs.web.filter.StartupFilter;
import org.openmrs.web.filter.update.UpdateFilter;
import org.openmrs.web.filter.util.CustomResourceLoader;
import org.openmrs.web.filter.util.ErrorMessageConstants;
import org.openmrs.web.filter.util.FilterUtil;
import org.slf4j.LoggerFactory;
import org.springframework.util.StringUtils;
import org.springframework.web.context.ContextLoader;

/**
 * This is the first filter that is processed. It is only active when starting OpenMRS for the very
 * first time. It will redirect all requests to the {@link WebConstants#SETUP_PAGE_URL} if the
 * {@link Listener} wasn't able to find any runtime properties
 */
public class InitializationFilter extends StartupFilter {
	
	private static final org.slf4j.Logger log = LoggerFactory.getLogger(InitializationFilter.class);
	
	private static final String DATABASE_POSTGRESQL = "postgresql";
	
	private static final String DATABASE_MYSQL = "mysql";
	
	private static final String DATABASE_SQLSERVER = "sqlserver";
	
	private static final String DATABASE_H2 = "h2";
	
	private static final String LIQUIBASE_DEMO_DATA = "liquibase-demo-data.xml";
	
	/**
	 * The very first page of wizard, that asks user for select his preferred language
	 */
	private static final String CHOOSE_LANG = "chooselang.vm";
	
	/**
	 * The second page of the wizard that asks for simple or advanced installation.
	 */
	private static final String INSTALL_METHOD = "installmethod.vm";
	
	/**
	 * The simple installation setup page.
	 */
	private static final String SIMPLE_SETUP = "simplesetup.vm";
	
	/**
	 * The first page of the advanced installation of the wizard that asks for a current or past
	 * database
	 */
	private static final String DATABASE_SETUP = "databasesetup.vm";
	
	/**
	 * The page from where the user specifies the url to a remote system, username and password
	 */
	private static final String TESTING_REMOTE_DETAILS_SETUP = "remotedetails.vm";
	
	/**
	 * The velocity macro page to redirect to if an error occurs or on initial startup
	 */
	private static final String DEFAULT_PAGE = CHOOSE_LANG;
	
	/**
	 * This page asks whether database tables/demo data should be inserted and what the
	 * username/password that will be put into the runtime properties is
	 */
	private static final String DATABASE_TABLES_AND_USER = "databasetablesanduser.vm";
	
	/**
	 * This page lets the user define the admin user
	 */
	private static final String ADMIN_USER_SETUP = "adminusersetup.vm";
	
	/**
	 * This page lets the user pick an implementation id
	 */
	private static final String IMPLEMENTATION_ID_SETUP = "implementationidsetup.vm";
	
	/**
	 * This page asks for settings that will be put into the runtime properties files
	 */
	private static final String OTHER_RUNTIME_PROPS = "otherruntimeproperties.vm";
	
	/**
	 * A page that tells the user that everything is collected and will now be processed
	 */
	private static final String WIZARD_COMPLETE = "wizardcomplete.vm";
	
	/**
	 * A page that lists off what is happening while it is going on. This page has ajax that callst he
	 * {@value #PROGRESS_VM_AJAXREQUEST} page
	 */
	private static final String PROGRESS_VM = "progress.vm";
	
	/**
	 * This url is called by javascript to get the status of the install
	 */
	private static final String PROGRESS_VM_AJAXREQUEST = "progress.vm.ajaxRequest";
	
	public static final String RELEASE_TESTING_MODULE_PATH = "/module/releasetestinghelper/";
	
	/**
	 * The model object that holds all the properties that the rendered templates use. All attributes on
	 * this object are made available to all templates via reflection in the
	 * {@link org.openmrs.web.filter.StartupFilter#renderTemplate(String, Map, HttpServletResponse)} method.
	 */
	private InitializationWizardModel wizardModel = null;
	
	private InitializationCompletion initJob;
	
	/**
	 * Variable set to true as soon as the installation begins and set to false when the process ends
	 * This thread should only be accesses through the synchronized method.
	 */
	private static boolean isInstallationStarted = false;
	
	// the actual driver loaded by the DatabaseUpdater class
	private String loadedDriverString;
	
	/**
	 * Variable set at the end of the wizard when spring is being restarted
	 */
	private static boolean initializationComplete = false;
	
	protected synchronized void setInitializationComplete(boolean initializationComplete) {
		InitializationFilter.initializationComplete = initializationComplete;
	}
	
	/**
	 * Called by {@link #doFilter(ServletRequest, ServletResponse, FilterChain)} on GET requests
	 *
	 * @param httpRequest
	 * @param httpResponse
	 */
	@Override
	protected void doGet(HttpServletRequest httpRequest, HttpServletResponse httpResponse)
	        throws IOException, ServletException {
		loadInstallationScriptIfPresent();
		
		// we need to save current user language in references map since it will be used when template
		// will be rendered
		if (httpRequest.getSession().getAttribute(FilterUtil.LOCALE_ATTRIBUTE) == null) {
			checkLocaleAttributesForFirstTime(httpRequest);
		}
		
		Map<String, Object> referenceMap = new HashMap<>();
		String page = httpRequest.getParameter("page");
		
		referenceMap.put(FilterUtil.LOCALE_ATTRIBUTE, httpRequest.getSession().getAttribute(FilterUtil.LOCALE_ATTRIBUTE));
		
		httpResponse.setHeader("Cache-Control", "no-cache");
		
		// if any body has already started installation and this is not an ajax request for the progress
		if (isInstallationStarted() && !PROGRESS_VM_AJAXREQUEST.equals(page)) {
			referenceMap.put("isInstallationStarted", true);
			httpResponse.setContentType("text/html");
			renderTemplate(PROGRESS_VM, referenceMap, httpResponse);
		} else if (PROGRESS_VM_AJAXREQUEST.equals(page)) {
			httpResponse.setContentType("text/json");
			Map<String, Object> result = new HashMap<>();
			if (initJob != null) {
				result.put("hasErrors", initJob.hasErrors());
				if (initJob.hasErrors()) {
					result.put("errorPage", initJob.getErrorPage());
					errors.putAll(initJob.getErrors());
				}
				
				result.put("initializationComplete", isInitializationComplete());
				result.put("message", initJob.getMessage());
				result.put("actionCounter", initJob.getStepsComplete());
				if (!isInitializationComplete()) {
					result.put("executingTask", initJob.getExecutingTask());
					result.put("executedTasks", initJob.getExecutedTasks());
					result.put("completedPercentage", initJob.getCompletedPercentage());
				}

				addLogLinesToResponse(result);
			}
			
			PrintWriter writer = httpResponse.getWriter();
			writer.write(toJSONString(result));
			writer.close();
		} else if (InitializationWizardModel.INSTALL_METHOD_AUTO.equals(wizardModel.installMethod)
		        || httpRequest.getServletPath().equals("/" + AUTO_RUN_OPENMRS)) {
			autoRunOpenMRS(httpRequest);
			referenceMap.put("isInstallationStarted", true);
			httpResponse.setContentType("text/html");
			renderTemplate(PROGRESS_VM, referenceMap, httpResponse);
		} else if (page == null) {
			httpResponse.setContentType("text/html");// if any body has already started installation
			
			//If someone came straight here without setting the hidden page input,
			// then we need to clear out all the passwords
			clearPasswords();
			
			renderTemplate(DEFAULT_PAGE, referenceMap, httpResponse);
		} else if (INSTALL_METHOD.equals(page)) {
			// get props and render the second page
			File runtimeProperties = getRuntimePropertiesFile();
			
			if (!runtimeProperties.exists()) {
				try {
					runtimeProperties.createNewFile();
					// reset the error objects in case of refresh
					wizardModel.canCreate = true;
					wizardModel.cannotCreateErrorMessage = "";
				}
				catch (IOException io) {
					wizardModel.canCreate = false;
					wizardModel.cannotCreateErrorMessage = io.getMessage();
				}
				
				// check this before deleting the file again
				wizardModel.canWrite = runtimeProperties.canWrite();
				
				// delete the file again after testing the create/write
				// so that if the user stops the webapp before finishing
				// this wizard, they can still get back into it
				runtimeProperties.delete();
				
			} else {
				wizardModel.canWrite = runtimeProperties.canWrite();
				
				wizardModel.databaseConnection = Context.getRuntimeProperties().getProperty("connection.url",
				    wizardModel.databaseConnection);
				
				wizardModel.currentDatabaseUsername = Context.getRuntimeProperties().getProperty("connection.username",
				    wizardModel.currentDatabaseUsername);
				
				wizardModel.currentDatabasePassword = Context.getRuntimeProperties().getProperty("connection.password",
				    wizardModel.currentDatabasePassword);
			}
			
			wizardModel.runtimePropertiesPath = runtimeProperties.getAbsolutePath();
			
			// do step one of the wizard
			httpResponse.setContentType("text/html");
			renderTemplate(INSTALL_METHOD, referenceMap, httpResponse);
		}
	}
	
	private void loadInstallationScriptIfPresent() {
		Properties script = getInstallationScript();
		if (!script.isEmpty()) {
			wizardModel.installMethod = script.getProperty("install_method", wizardModel.installMethod);
			
			wizardModel.databaseConnection = script.getProperty("connection.url", wizardModel.databaseConnection);
			wizardModel.databaseDriver = script.getProperty("connection.driver_class", wizardModel.databaseDriver);
			wizardModel.currentDatabaseUsername = script.getProperty("connection.username",
			    wizardModel.currentDatabaseUsername);
			wizardModel.currentDatabasePassword = script.getProperty("connection.password",
			    wizardModel.currentDatabasePassword);
			
			String hasCurrentOpenmrsDatabase = script.getProperty("has_current_openmrs_database");
			if (hasCurrentOpenmrsDatabase != null) {
				wizardModel.hasCurrentOpenmrsDatabase = Boolean.valueOf(hasCurrentOpenmrsDatabase);
			}
			wizardModel.createDatabaseUsername = script.getProperty("create_database_username",
			    wizardModel.createDatabaseUsername);
			wizardModel.createDatabasePassword = script.getProperty("create_database_password",
			    wizardModel.createDatabasePassword);
			
			String createTables = script.getProperty("create_tables");
			if (createTables != null) {
				wizardModel.createTables = Boolean.valueOf(createTables);
			}
			
			String createDatabaseUser = script.getProperty("create_database_user");
			if (createDatabaseUser != null) {
				wizardModel.createDatabaseUser = Boolean.valueOf(createDatabaseUser);
			}
			wizardModel.createUserUsername = script.getProperty("create_user_username", wizardModel.createUserUsername);
			wizardModel.createUserPassword = script.getProperty("create_user_password", wizardModel.createUserPassword);
			
			String addDemoData = script.getProperty("add_demo_data");
			if (addDemoData != null) {
				wizardModel.addDemoData = Boolean.valueOf(addDemoData);
			}
			
			String moduleWebAdmin = script.getProperty("module_web_admin");
			if (moduleWebAdmin != null) {
				wizardModel.moduleWebAdmin = Boolean.valueOf(moduleWebAdmin);
			}
			
			String autoUpdateDatabase = script.getProperty("auto_update_database");
			if (autoUpdateDatabase != null) {
				wizardModel.autoUpdateDatabase = Boolean.valueOf(autoUpdateDatabase);
			}
			
			wizardModel.adminUserPassword = script.getProperty("admin_user_password", wizardModel.adminUserPassword);
		}
	}
	
	private void clearPasswords() {
		wizardModel.databaseRootPassword = "";
		wizardModel.createDatabasePassword = "";
		wizardModel.createUserPassword = "";
		wizardModel.currentDatabasePassword = "";
		wizardModel.remotePassword = "";
	}
	
	/**
	 * Called by {@link #doFilter(ServletRequest, ServletResponse, FilterChain)} on POST requests
	 *
	 * @param httpRequest
	 * @param httpResponse
	 */
	@Override
	protected void doPost(HttpServletRequest httpRequest, HttpServletResponse httpResponse)
	        throws IOException, ServletException {
		String page = httpRequest.getParameter("page");
		Map<String, Object> referenceMap = new HashMap<>();
		// we need to save current user language in references map since it will be used when template
		// will be rendered
		if (httpRequest.getSession().getAttribute(FilterUtil.LOCALE_ATTRIBUTE) != null) {
			referenceMap.put(FilterUtil.LOCALE_ATTRIBUTE,
			    httpRequest.getSession().getAttribute(FilterUtil.LOCALE_ATTRIBUTE));
		}
		
		// if any body has already started installation
		if (isInstallationStarted()) {
			referenceMap.put("isInstallationStarted", true);
			httpResponse.setContentType("text/html");
			renderTemplate(PROGRESS_VM, referenceMap, httpResponse);
			return;
		}
		if (DEFAULT_PAGE.equals(page)) {
			// get props and render the first page
			File runtimeProperties = getRuntimePropertiesFile();
			if (!runtimeProperties.exists()) {
				try {
					runtimeProperties.createNewFile();
					// reset the error objects in case of refresh
					wizardModel.canCreate = true;
					wizardModel.cannotCreateErrorMessage = "";
				}
				catch (IOException io) {
					wizardModel.canCreate = false;
					wizardModel.cannotCreateErrorMessage = io.getMessage();
				}
				// check this before deleting the file again
				wizardModel.canWrite = runtimeProperties.canWrite();
				
				// delete the file again after testing the create/write
				// so that if the user stops the webapp before finishing
				// this wizard, they can still get back into it
				runtimeProperties.delete();
			} else {
				wizardModel.canWrite = runtimeProperties.canWrite();
				
				wizardModel.databaseConnection = Context.getRuntimeProperties().getProperty("connection.url",
				    wizardModel.databaseConnection);
				
				wizardModel.currentDatabaseUsername = Context.getRuntimeProperties().getProperty("connection.username",
				    wizardModel.currentDatabaseUsername);
				
				wizardModel.currentDatabasePassword = Context.getRuntimeProperties().getProperty("connection.password",
				    wizardModel.currentDatabasePassword);
			}
			
			wizardModel.runtimePropertiesPath = runtimeProperties.getAbsolutePath();
			
			checkLocaleAttributes(httpRequest);
			referenceMap.put(FilterUtil.LOCALE_ATTRIBUTE,
			    httpRequest.getSession().getAttribute(FilterUtil.LOCALE_ATTRIBUTE));
			log.info("Locale stored in session is " + httpRequest.getSession().getAttribute(FilterUtil.LOCALE_ATTRIBUTE));
			
			httpResponse.setContentType("text/html");
			// otherwise do step one of the wizard
			renderTemplate(INSTALL_METHOD, referenceMap, httpResponse);
		} else if (INSTALL_METHOD.equals(page)) {
			if (goBack(httpRequest)) {
				referenceMap.put(FilterUtil.REMEMBER_ATTRIBUTE,
				    httpRequest.getSession().getAttribute(FilterUtil.REMEMBER_ATTRIBUTE) != null);
				referenceMap.put(FilterUtil.LOCALE_ATTRIBUTE,
				    httpRequest.getSession().getAttribute(FilterUtil.LOCALE_ATTRIBUTE));
				renderTemplate(CHOOSE_LANG, referenceMap, httpResponse);
				return;
			}
			wizardModel.installMethod = httpRequest.getParameter("install_method");
			if (InitializationWizardModel.INSTALL_METHOD_SIMPLE.equals(wizardModel.installMethod)) {
				page = SIMPLE_SETUP;
			} else if (InitializationWizardModel.INSTALL_METHOD_TESTING.equals(wizardModel.installMethod)) {
				page = TESTING_REMOTE_DETAILS_SETUP;
				wizardModel.currentStepNumber = 1;
				wizardModel.numberOfSteps = skipDatabaseSetupPage() ? 1 : 3;
			} else {
				page = DATABASE_SETUP;
				wizardModel.currentStepNumber = 1;
				wizardModel.numberOfSteps = 5;
			}
			renderTemplate(page, referenceMap, httpResponse);
		} // simple method
		else if (SIMPLE_SETUP.equals(page)) {
			if (goBack(httpRequest)) {
				renderTemplate(INSTALL_METHOD, referenceMap, httpResponse);
				return;
			}
			wizardModel.databaseConnection = httpRequest.getParameter("database_connection");;
			
			wizardModel.createDatabaseUsername = Context.getRuntimeProperties().getProperty("connection.username",
			    wizardModel.createDatabaseUsername);
			
			wizardModel.createUserUsername = wizardModel.createDatabaseUsername;
			
			wizardModel.databaseRootPassword = httpRequest.getParameter("database_root_password");
			checkForEmptyValue(wizardModel.databaseRootPassword, errors, ErrorMessageConstants.ERROR_DB_PSDW_REQ);
			
			wizardModel.hasCurrentOpenmrsDatabase = false;
			wizardModel.createTables = true;
			// default wizardModel.databaseName is openmrs
			// default wizardModel.createDatabaseUsername is root
			wizardModel.createDatabasePassword = wizardModel.databaseRootPassword;
			wizardModel.addDemoData = "yes".equals(httpRequest.getParameter("add_demo_data"));
			
			wizardModel.hasCurrentDatabaseUser = false;
			wizardModel.createDatabaseUser = true;
			// default wizardModel.createUserUsername is root
			wizardModel.createUserPassword = wizardModel.databaseRootPassword;
			
			wizardModel.moduleWebAdmin = true;
			wizardModel.autoUpdateDatabase = false;
			
			wizardModel.adminUserPassword = InitializationWizardModel.ADMIN_DEFAULT_PASSWORD;
			
			createSimpleSetup(httpRequest.getParameter("database_root_password"), httpRequest.getParameter("add_demo_data"));
			
			try {
				loadedDriverString = DatabaseUtil.loadDatabaseDriver(wizardModel.databaseConnection,
				    wizardModel.databaseDriver);
			}
			catch (ClassNotFoundException e) {
				errors.put(ErrorMessageConstants.ERROR_DB_DRIVER_CLASS_REQ, null);
				renderTemplate(page, referenceMap, httpResponse);
				return;
			}
			
			if (errors.isEmpty()) {
				page = WIZARD_COMPLETE;
			}
			renderTemplate(page, referenceMap, httpResponse);
		} // step one
		else if (DATABASE_SETUP.equals(page)) {
			if (goBack(httpRequest)) {
				wizardModel.currentStepNumber -= 1;
				if (InitializationWizardModel.INSTALL_METHOD_TESTING.equals(wizardModel.installMethod)) {
					renderTemplate(TESTING_REMOTE_DETAILS_SETUP, referenceMap, httpResponse);
				} else {
					renderTemplate(INSTALL_METHOD, referenceMap, httpResponse);
				}
				return;
			}
			
			wizardModel.databaseConnection = httpRequest.getParameter("database_connection");
			checkForEmptyValue(wizardModel.databaseConnection, errors, ErrorMessageConstants.ERROR_DB_CONN_REQ);
			
			wizardModel.databaseDriver = httpRequest.getParameter("database_driver");
			checkForEmptyValue(wizardModel.databaseConnection, errors, ErrorMessageConstants.ERROR_DB_DRIVER_REQ);
			
			loadedDriverString = loadDriver(wizardModel.databaseConnection, wizardModel.databaseDriver);
			if (!StringUtils.hasText(loadedDriverString)) {
				errors.put(ErrorMessageConstants.ERROR_DB_DRIVER_CLASS_REQ, null);
				renderTemplate(page, referenceMap, httpResponse);
				return;
			}
			
			//TODO make each bit of page logic a (unit testable) method
			
			// asked the user for their desired database name
			
			if ("yes".equals(httpRequest.getParameter("current_openmrs_database"))) {
				wizardModel.databaseName = httpRequest.getParameter("openmrs_current_database_name");
				checkForEmptyValue(wizardModel.databaseName, errors, ErrorMessageConstants.ERROR_DB_CURR_NAME_REQ);
				wizardModel.hasCurrentOpenmrsDatabase = true;
				// TODO check to see if this is an active database
				
			} else {
				// mark this wizard as a "to create database" (done at the end)
				wizardModel.hasCurrentOpenmrsDatabase = false;
				
				wizardModel.createTables = true;
				
				wizardModel.databaseName = httpRequest.getParameter("openmrs_new_database_name");
				checkForEmptyValue(wizardModel.databaseName, errors, ErrorMessageConstants.ERROR_DB_NEW_NAME_REQ);
				// TODO create database now to check if its possible?
				
				wizardModel.createDatabaseUsername = httpRequest.getParameter("create_database_username");
				checkForEmptyValue(wizardModel.createDatabaseUsername, errors, ErrorMessageConstants.ERROR_DB_USER_NAME_REQ);
				wizardModel.createDatabasePassword = httpRequest.getParameter("create_database_password");
				checkForEmptyValue(wizardModel.createDatabasePassword, errors, ErrorMessageConstants.ERROR_DB_USER_PSWD_REQ);
			}
			
			if (errors.isEmpty()) {
				page = DATABASE_TABLES_AND_USER;
				
				if (InitializationWizardModel.INSTALL_METHOD_TESTING.equals(wizardModel.installMethod)) {
					wizardModel.currentStepNumber = 3;
				} else {
					wizardModel.currentStepNumber = 2;
				}
			}
			
			renderTemplate(page, referenceMap, httpResponse);
			
		} // step two
		else if (DATABASE_TABLES_AND_USER.equals(page)) {
			
			if (goBack(httpRequest)) {
				wizardModel.currentStepNumber -= 1;
				renderTemplate(DATABASE_SETUP, referenceMap, httpResponse);
				return;
			}
			
			if (wizardModel.hasCurrentOpenmrsDatabase) {
				wizardModel.createTables = "yes".equals(httpRequest.getParameter("create_tables"));
			}
			
			wizardModel.addDemoData = "yes".equals(httpRequest.getParameter("add_demo_data"));
			
			if ("yes".equals(httpRequest.getParameter("current_database_user"))) {
				wizardModel.currentDatabaseUsername = httpRequest.getParameter("current_database_username");
				checkForEmptyValue(wizardModel.currentDatabaseUsername, errors,
				    ErrorMessageConstants.ERROR_DB_CUR_USER_NAME_REQ);
				wizardModel.currentDatabasePassword = httpRequest.getParameter("current_database_password");
				checkForEmptyValue(wizardModel.currentDatabasePassword, errors,
				    ErrorMessageConstants.ERROR_DB_CUR_USER_PSWD_REQ);
				wizardModel.hasCurrentDatabaseUser = true;
				wizardModel.createDatabaseUser = false;
			} else {
				wizardModel.hasCurrentDatabaseUser = false;
				wizardModel.createDatabaseUser = true;
				// asked for the root mysql username/password
				wizardModel.createUserUsername = httpRequest.getParameter("create_user_username");
				checkForEmptyValue(wizardModel.createUserUsername, errors, ErrorMessageConstants.ERROR_DB_USER_NAME_REQ);
				wizardModel.createUserPassword = httpRequest.getParameter("create_user_password");
				checkForEmptyValue(wizardModel.createUserPassword, errors, ErrorMessageConstants.ERROR_DB_USER_PSWD_REQ);
			}
			
			if (errors.isEmpty()) { // go to next page
				page = InitializationWizardModel.INSTALL_METHOD_TESTING.equals(wizardModel.installMethod) ? WIZARD_COMPLETE
				        : OTHER_RUNTIME_PROPS;
			}
			
			renderTemplate(page, referenceMap, httpResponse);
		} // step three
		else if (OTHER_RUNTIME_PROPS.equals(page)) {
			
			if (goBack(httpRequest)) {
				renderTemplate(DATABASE_TABLES_AND_USER, referenceMap, httpResponse);
				return;
			}
			
			wizardModel.moduleWebAdmin = "yes".equals(httpRequest.getParameter("module_web_admin"));
			wizardModel.autoUpdateDatabase = "yes".equals(httpRequest.getParameter("auto_update_database"));
			
			if (wizardModel.createTables) { // go to next page if they are creating tables
				page = ADMIN_USER_SETUP;
			} else { // skip a page
				page = IMPLEMENTATION_ID_SETUP;
			}
			
			renderTemplate(page, referenceMap, httpResponse);
			
		} // optional step four
		else if (ADMIN_USER_SETUP.equals(page)) {
			
			if (goBack(httpRequest)) {
				renderTemplate(OTHER_RUNTIME_PROPS, referenceMap, httpResponse);
				return;
			}
			
			wizardModel.adminUserPassword = httpRequest.getParameter("new_admin_password");
			String adminUserConfirm = httpRequest.getParameter("new_admin_password_confirm");
			
			// throw back to admin user if passwords don't match
			if (!wizardModel.adminUserPassword.equals(adminUserConfirm)) {
				errors.put(ErrorMessageConstants.ERROR_DB_ADM_PSWDS_MATCH, null);
				renderTemplate(ADMIN_USER_SETUP, referenceMap, httpResponse);
				return;
			}
			
			// throw back if the user didn't put in a password
			if ("".equals(wizardModel.adminUserPassword)) {
				errors.put(ErrorMessageConstants.ERROR_DB_ADM_PSDW_EMPTY, null);
				renderTemplate(ADMIN_USER_SETUP, referenceMap, httpResponse);
				return;
			}
			
			try {
				OpenmrsUtil.validatePassword("admin", wizardModel.adminUserPassword, "admin");
			}
			catch (PasswordException p) {
				errors.put(ErrorMessageConstants.ERROR_DB_ADM_PSDW_WEAK, null);
				renderTemplate(ADMIN_USER_SETUP, referenceMap, httpResponse);
				return;
			}
			
			if (errors.isEmpty()) { // go to next page
				page = IMPLEMENTATION_ID_SETUP;
			}
			
			renderTemplate(page, referenceMap, httpResponse);
			
		} // optional step five
		else if (IMPLEMENTATION_ID_SETUP.equals(page)) {
			
			if (goBack(httpRequest)) {
				if (wizardModel.createTables) {
					renderTemplate(ADMIN_USER_SETUP, referenceMap, httpResponse);
				} else {
					renderTemplate(OTHER_RUNTIME_PROPS, referenceMap, httpResponse);
				}
				return;
			}
			
			wizardModel.implementationIdName = httpRequest.getParameter("implementation_name");
			wizardModel.implementationId = httpRequest.getParameter("implementation_id");
			wizardModel.implementationIdPassPhrase = httpRequest.getParameter("pass_phrase");
			wizardModel.implementationIdDescription = httpRequest.getParameter("description");
			
			// throw back if the user-specified ID is invalid (contains ^ or |).
			if (wizardModel.implementationId.indexOf('^') != -1 || wizardModel.implementationId.indexOf('|') != -1) {
				errors.put(ErrorMessageConstants.ERROR_DB_IMPL_ID_REQ, null);
				renderTemplate(IMPLEMENTATION_ID_SETUP, referenceMap, httpResponse);
				return;
			}
			
			if (errors.isEmpty()) { // go to next page
				page = WIZARD_COMPLETE;
			}
			
			renderTemplate(page, referenceMap, httpResponse);
		} else if (WIZARD_COMPLETE.equals(page)) {
			
			if (goBack(httpRequest)) {
				
				if (InitializationWizardModel.INSTALL_METHOD_SIMPLE.equals(wizardModel.installMethod)) {
					page = SIMPLE_SETUP;
				} else if (InitializationWizardModel.INSTALL_METHOD_TESTING.equals(wizardModel.installMethod)) {
					if (skipDatabaseSetupPage()) {
						page = TESTING_REMOTE_DETAILS_SETUP;
					} else {
						page = DATABASE_TABLES_AND_USER;
					}
				} else {
					page = IMPLEMENTATION_ID_SETUP;
				}
				renderTemplate(page, referenceMap, httpResponse);
				return;
			}
			
			wizardModel.tasksToExecute = new ArrayList<>();
			createDatabaseTask();
			if (InitializationWizardModel.INSTALL_METHOD_TESTING.equals(wizardModel.installMethod)) {
				wizardModel.importTestData = true;
				wizardModel.createTables = false;
				wizardModel.addDemoData = false;
				//if we have a runtime properties file
				if (skipDatabaseSetupPage()) {
					wizardModel.hasCurrentOpenmrsDatabase = false;
					wizardModel.hasCurrentDatabaseUser = true;
					wizardModel.createDatabaseUser = false;
					Properties props = OpenmrsUtil.getRuntimeProperties(WebConstants.WEBAPP_NAME);
					wizardModel.currentDatabaseUsername = props.getProperty("connection.username");
					wizardModel.currentDatabasePassword = props.getProperty("connection.password");
					wizardModel.createDatabaseUsername = wizardModel.currentDatabaseUsername;
					wizardModel.createDatabasePassword = wizardModel.currentDatabasePassword;
				}
				
				wizardModel.tasksToExecute.add(WizardTask.IMPORT_TEST_DATA);
				wizardModel.tasksToExecute.add(WizardTask.ADD_MODULES);
			} else {
				createTablesTask();
				createDemoDataTask();
			}
			wizardModel.tasksToExecute.add(WizardTask.UPDATE_TO_LATEST);
			
			referenceMap.put("tasksToExecute", wizardModel.tasksToExecute);
			startInstallation();
			renderTemplate(PROGRESS_VM, referenceMap, httpResponse);
		} else if (TESTING_REMOTE_DETAILS_SETUP.equals(page)) {
			if (goBack(httpRequest)) {
				wizardModel.currentStepNumber -= 1;
				renderTemplate(INSTALL_METHOD, referenceMap, httpResponse);
				return;
			}
			
			wizardModel.remoteUrl = httpRequest.getParameter("remoteUrl");
			checkForEmptyValue(wizardModel.remoteUrl, errors, "install.testing.remote.url.required");
			if (errors.isEmpty()) {
				//Check if the remote system is running
				if (TestInstallUtil.testConnection(wizardModel.remoteUrl)) {
					//Check if the test module is installed by connecting to its setting page
					if (TestInstallUtil
					        .testConnection(wizardModel.remoteUrl.concat(RELEASE_TESTING_MODULE_PATH + "settings.htm"))) {
						
						wizardModel.remoteUsername = httpRequest.getParameter("username");
						wizardModel.remotePassword = httpRequest.getParameter("password");
						checkForEmptyValue(wizardModel.remoteUsername, errors, "install.testing.username.required");
						checkForEmptyValue(wizardModel.remotePassword, errors, "install.testing.password.required");
						
						if (errors.isEmpty()) {
							//check if the username and password are valid
							try {
								TestInstallUtil.getResourceInputStream(
								    wizardModel.remoteUrl + RELEASE_TESTING_MODULE_PATH + "verifycredentials.htm",
								    wizardModel.remoteUsername, wizardModel.remotePassword);
							}
							catch (APIAuthenticationException e) {
								log.debug("Error generated: ", e);
								page = TESTING_REMOTE_DETAILS_SETUP;
								errors.put(ErrorMessageConstants.UPDATE_ERROR_UNABLE_AUTHENTICATE, null);
								renderTemplate(page, referenceMap, httpResponse);
								return;
							}
							
							//If we have a runtime properties file, get the database setup details from it
							if (skipDatabaseSetupPage()) {
								Properties props = OpenmrsUtil.getRuntimeProperties(WebConstants.WEBAPP_NAME);
								wizardModel.databaseConnection = props.getProperty("connection.url");
								loadedDriverString = loadDriver(wizardModel.databaseConnection, wizardModel.databaseDriver);
								if (!StringUtils.hasText(loadedDriverString)) {
									page = TESTING_REMOTE_DETAILS_SETUP;
									errors.put(ErrorMessageConstants.ERROR_DB_DRIVER_CLASS_REQ, null);
									renderTemplate(page, referenceMap, httpResponse);
									return;
								}
								
								wizardModel.databaseName = InitializationWizardModel.DEFAULT_DATABASE_NAME;
								page = WIZARD_COMPLETE;
							} else {
								page = DATABASE_SETUP;
								wizardModel.currentStepNumber = 2;
							}
							msgs.put("install.testing.testingModuleFound", null);
						} else {
							renderTemplate(page, referenceMap, httpResponse);
							return;
						}
					} else {
						errors.put("install.testing.noTestingModule", null);
					}
				} else {
					errors.put("install.testing.invalidProductionUrl", new Object[] { wizardModel.remoteUrl });
				}
			}
			
			renderTemplate(page, referenceMap, httpResponse);
		}
	}
	
	private void startInstallation() {
		//if no one has run any installation
		if (!isInstallationStarted()) {
			initJob = new InitializationCompletion();
			setInstallationStarted(true);
			initJob.start();
		}
	}
	
	private void createDemoDataTask() {
		if (wizardModel.addDemoData) {
			wizardModel.tasksToExecute.add(WizardTask.ADD_DEMO_DATA);
		}
	}
	
	private void createTablesTask() {
		if (wizardModel.createTables) {
			wizardModel.tasksToExecute.add(WizardTask.CREATE_TABLES);
			wizardModel.tasksToExecute.add(WizardTask.ADD_CORE_DATA);
		}
	}
	
	private void createDatabaseTask() {
		if (!wizardModel.hasCurrentOpenmrsDatabase) {
			wizardModel.tasksToExecute.add(WizardTask.CREATE_SCHEMA);
		}
		if (wizardModel.createDatabaseUser) {
			wizardModel.tasksToExecute.add(WizardTask.CREATE_DB_USER);
		}
	}
	
	private void createSimpleSetup(String databaseRootPassword, String addDemoData) {
		setDatabaseNameIfInTestMode();
		wizardModel.databaseConnection = Context.getRuntimeProperties().getProperty("connection.url",
		    wizardModel.databaseConnection);
		
		wizardModel.createDatabaseUsername = Context.getRuntimeProperties().getProperty("connection.username",
		    wizardModel.createDatabaseUsername);
		
		wizardModel.createUserUsername = wizardModel.createDatabaseUsername;
		
		wizardModel.databaseRootPassword = databaseRootPassword;
		checkForEmptyValue(wizardModel.databaseRootPassword, errors, ErrorMessageConstants.ERROR_DB_PSDW_REQ);
		
		wizardModel.hasCurrentOpenmrsDatabase = false;
		wizardModel.createTables = true;
		// default wizardModel.databaseName is openmrs
		// default wizardModel.createDatabaseUsername is root
		wizardModel.createDatabasePassword = wizardModel.databaseRootPassword;
		wizardModel.addDemoData = "yes".equals(addDemoData);
		
		wizardModel.hasCurrentDatabaseUser = false;
		wizardModel.createDatabaseUser = true;
		// default wizardModel.createUserUsername is root
		wizardModel.createUserPassword = wizardModel.databaseRootPassword;
		
		wizardModel.moduleWebAdmin = true;
		wizardModel.autoUpdateDatabase = false;
		
		wizardModel.adminUserPassword = InitializationWizardModel.ADMIN_DEFAULT_PASSWORD;
	}
	
	private void setDatabaseNameIfInTestMode() {
		if (OpenmrsUtil.isTestMode()) {
			wizardModel.databaseName = OpenmrsUtil.getOpenMRSVersionInTestMode();
		}
	}
	
	private void autoRunOpenMRS(HttpServletRequest httpRequest) {
		File runtimeProperties = getRuntimePropertiesFile();
		wizardModel.runtimePropertiesPath = runtimeProperties.getAbsolutePath();
		
		if (!InitializationWizardModel.INSTALL_METHOD_AUTO.equals(wizardModel.installMethod)) {
			if (httpRequest.getParameter("database_user_name") != null) {
				wizardModel.createDatabaseUsername = httpRequest.getParameter("database_user_name");
			}
			
			createSimpleSetup(httpRequest.getParameter("database_root_password"), "yes");
		}
		
		checkLocaleAttributes(httpRequest);
		try {
			loadedDriverString = DatabaseUtil.loadDatabaseDriver(wizardModel.databaseConnection, wizardModel.databaseDriver);
		}
		catch (ClassNotFoundException e) {
			errors.put(ErrorMessageConstants.ERROR_DB_DRIVER_CLASS_REQ, null);
			return;
		}
		wizardModel.tasksToExecute = new ArrayList<>();
		createDatabaseTask();
		createTablesTask();
		createDemoDataTask();
		wizardModel.tasksToExecute.add(WizardTask.UPDATE_TO_LATEST);
		startInstallation();
	}
	
	/**
	 * This method should be called after the user has left wizard's first page (i.e. choose language).
	 * It checks if user has changed any of locale related parameters and makes appropriate corrections
	 * with filter's model or/and with locale attribute inside user's session.
	 *
	 * @param httpRequest the http request object
	 */
	private void checkLocaleAttributes(HttpServletRequest httpRequest) {
		String localeParameter = httpRequest.getParameter(FilterUtil.LOCALE_ATTRIBUTE);
		Boolean rememberLocale = false;
		// we need to check if user wants that system will remember his selection of language
		if (httpRequest.getParameter(FilterUtil.REMEMBER_ATTRIBUTE) != null) {
			rememberLocale = true;
		}
		if (localeParameter != null) {
			String storedLocale = null;
			if (httpRequest.getSession().getAttribute(FilterUtil.LOCALE_ATTRIBUTE) != null) {
				storedLocale = httpRequest.getSession().getAttribute(FilterUtil.LOCALE_ATTRIBUTE).toString();
			}
			// if user has changed locale parameter to new one
			// or chooses it parameter at first page loading
			if (storedLocale == null || !storedLocale.equals(localeParameter)) {
				log.info("Stored locale parameter to session " + localeParameter);
				httpRequest.getSession().setAttribute(FilterUtil.LOCALE_ATTRIBUTE, localeParameter);
			}
			if (rememberLocale) {
				httpRequest.getSession().setAttribute(FilterUtil.LOCALE_ATTRIBUTE, localeParameter);
				httpRequest.getSession().setAttribute(FilterUtil.REMEMBER_ATTRIBUTE, true);
				wizardModel.localeToSave = localeParameter;
			} else {
				// we need to reset it if it was set before
				httpRequest.getSession().setAttribute(FilterUtil.REMEMBER_ATTRIBUTE, null);
				wizardModel.localeToSave = null;
			}
		}
	}
	
	/**
	 * It sets locale parameter for current session when user is making first GET http request to
	 * application. It retrieves user locale from request object and checks if this locale is supported
	 * by application. If not, it uses {@link Locale#ENGLISH} by default
	 *
	 * @param httpRequest the http request object
	 */
	public void checkLocaleAttributesForFirstTime(HttpServletRequest httpRequest) {
		Locale locale = httpRequest.getLocale();
		if (CustomResourceLoader.getInstance(httpRequest).getAvailablelocales().contains(locale)) {
			httpRequest.getSession().setAttribute(FilterUtil.LOCALE_ATTRIBUTE, locale.toString());
		} else {
			httpRequest.getSession().setAttribute(FilterUtil.LOCALE_ATTRIBUTE, Locale.ENGLISH.toString());
		}
	}
	
	/**
	 * Verify the database connection works.
	 *
	 * @param connectionUsername
	 * @param connectionPassword
	 * @param databaseConnectionFinalUrl
	 * @return true/false whether it was verified or not
	 */
	private boolean verifyConnection(String connectionUsername, String connectionPassword,
	        String databaseConnectionFinalUrl) {
		try {
			// verify connection
			//Set Database Driver using driver String
			Class.forName(loadedDriverString).newInstance();
			Connection tempConnection = DriverManager.getConnection(databaseConnectionFinalUrl, connectionUsername,
			    connectionPassword);
			tempConnection.close();
			return true;
			
		}
		catch (Exception e) {
			errors.put("User account " + connectionUsername + " does not work. " + e.getMessage()
			        + " See the error log for more details",
			    null); // TODO internationalize this
			log.warn("Error while checking the connection user account", e);
			return false;
		}
	}
	
	/**
	 * Convenience method to load the runtime properties file.
	 *
	 * @return the runtime properties file.
	 */
	private File getRuntimePropertiesFile() {
		File file;
		
		String pathName = OpenmrsUtil.getRuntimePropertiesFilePathName(WebConstants.WEBAPP_NAME);
		if (pathName != null) {
			file = new File(pathName);
		} else {
			file = new File(OpenmrsUtil.getApplicationDataDirectory(), getRuntimePropertiesFileName());
		}
		
		log.debug("Using file: " + file.getAbsolutePath());
		
		return file;
	}
	
	private String getRuntimePropertiesFileName() {
		String fileName = OpenmrsUtil.getRuntimePropertiesFileNameInTestMode();
		if (fileName == null) {
			fileName = WebConstants.WEBAPP_NAME + "-runtime.properties";
		}
		return fileName;
	}
	
	/**
	 * @see org.openmrs.web.filter.StartupFilter#getTemplatePrefix()
	 */
	@Override
	protected String getTemplatePrefix() {
		return "org/openmrs/web/filter/initialization/";
	}
	
	/**
	 * @see org.openmrs.web.filter.StartupFilter#getUpdateFilterModel()
	 */
	@Override
	protected Object getUpdateFilterModel() {
		return wizardModel;
	}
	
	/**
	 * @see org.openmrs.web.filter.StartupFilter#skipFilter(HttpServletRequest)
	 */
	@Override
	public boolean skipFilter(HttpServletRequest httpRequest) {
		// If progress.vm makes an ajax request even immediately after initialization has completed
		// let the request pass in order to let progress.vm load the start page of OpenMRS
		// (otherwise progress.vm is displayed "forever")
		return !PROGRESS_VM_AJAXREQUEST.equals(httpRequest.getParameter("page")) && !initializationRequired();
	}
	
	/**
	 * Public method that returns true if database+runtime properties initialization is required
	 *
	 * @return true if this initialization wizard needs to run
	 */
	public static boolean initializationRequired() {
		return !isInitializationComplete();
	}
	
	/**
	 * @param isInstallationStarted the value to set
	 */
	protected static synchronized void setInstallationStarted(boolean isInstallationStarted) {
		InitializationFilter.isInstallationStarted = isInstallationStarted;
	}
	
	/**
	 * @return true if installation has been started
	 */
	protected static boolean isInstallationStarted() {
		return isInstallationStarted;
	}
	
	/**
	 * @see javax.servlet.Filter#init(javax.servlet.FilterConfig)
	 */
	@Override
	public void init(FilterConfig filterConfig) throws ServletException {
		super.init(filterConfig);
		wizardModel = new InitializationWizardModel();
		DatabaseDetective databaseDetective = new DatabaseDetective();
		//set whether need to do initialization work
		if (databaseDetective.isDatabaseEmpty(OpenmrsUtil.getRuntimeProperties(WebConstants.WEBAPP_NAME))) {
			//if runtime-properties file doesn't exist, have to do initialization work
			setInitializationComplete(false);
		} else {
			//if database is not empty, then let UpdaterFilter to judge whether need database update
			setInitializationComplete(true);
		}
	}
	
	private void importTestDataSet(InputStream in, String connectionUrl, String connectionUsername,
	        String connectionPassword) throws IOException {
		File tempFile = null;
		FileOutputStream fileOut = null;
		try {
			ZipInputStream zipIn = new ZipInputStream(in);
			zipIn.getNextEntry();
			
			tempFile = File.createTempFile("testDataSet", "dump");
			fileOut = new FileOutputStream(tempFile);
			
			IOUtils.copy(zipIn, fileOut);
			
			fileOut.close();
			zipIn.close();
			
			//Cater for the stand-alone connection url with has :mxj:
			if (connectionUrl.contains(":mxj:")) {
				connectionUrl = connectionUrl.replace(":mxj:", ":");
			}
			
			URI uri = URI.create(connectionUrl.substring(5)); //remove 'jdbc:' prefix to conform to the URI format
			String host = uri.getHost();
			int port = uri.getPort();
			
			TestInstallUtil.addTestData(host, port, wizardModel.databaseName, connectionUsername, connectionPassword,
			    tempFile.getAbsolutePath());
		}
		finally {
			IOUtils.closeQuietly(in);
			IOUtils.closeQuietly(fileOut);
			
			if (tempFile != null) {
				tempFile.delete();
			}
		}
	}
	
	private boolean isCurrentDatabase(String database) {
		return wizardModel.databaseConnection.contains(database);
	}
	
	/**
	 * @param silent if this statement fails do not display stack trace or record an error in the wizard
	 *            object.
	 * @param user username to connect with
	 * @param pw password to connect with
	 * @param sql String containing sql and question marks
	 * @param args the strings to fill into the question marks in the given sql
	 * @return result of executeUpdate or -1 for error
	 */
	private int executeStatement(boolean silent, String user, String pw, String sql, String... args) {
		
		Connection connection = null;
		Statement statement = null;
		try {
			String replacedSql = sql;
			
			// TODO how to get the driver for the other dbs...
			if (isCurrentDatabase(DATABASE_MYSQL)) {
				Class.forName("com.mysql.cj.jdbc.Driver").newInstance();
			} else if (isCurrentDatabase(DATABASE_POSTGRESQL)) {
				Class.forName("org.postgresql.Driver").newInstance();
				replacedSql = replacedSql.replaceAll("`", "\"");
			} else {
				replacedSql = replacedSql.replaceAll("`", "\"");
			}
			
			String tempDatabaseConnection;
			if (sql.contains("create database")) {
				tempDatabaseConnection = wizardModel.databaseConnection.replace("@DBNAME@", ""); // make this dbname agnostic so we can create the db
			} else {
				tempDatabaseConnection = wizardModel.databaseConnection.replace("@DBNAME@", wizardModel.databaseName);
			}
			
			connection = DriverManager.getConnection(tempDatabaseConnection, user, pw);
			
			for (String arg : args) {
				arg = arg.replace(";", "&#094"); // to prevent any sql injection
				replacedSql = replacedSql.replaceFirst("\\?", arg);
			}
			
			// run the sql statement
			statement = connection.createStatement();
			
			return statement.executeUpdate(replacedSql);
			
		}
		catch (SQLException sqlex) {
			if (!silent) {
				// log and add error
				log.warn("error executing sql: " + sql, sqlex);
				errors.put("Error executing sql: " + sql + " - " + sqlex.getMessage(), null);
			}
		}
		catch (InstantiationException | ClassNotFoundException | IllegalAccessException e) {
			log.error("Error generated", e);
		}
		finally {
			try {
				if (statement != null) {
					statement.close();
				}
			}
			catch (SQLException e) {
				log.warn("Error while closing statement");
			}
			try {
				
				if (connection != null) {
					connection.close();
				}
			}
			catch (Exception e) {
				log.warn("Error while closing connection", e);
			}
		}
		
		return -1;
	}
	
	/**
	 * Convenience variable to know if this wizard has completed successfully and that this wizard does
	 * not need to be executed again
	 *
	 * @return true if this has been run already
	 */
	private static synchronized boolean isInitializationComplete() {
		return initializationComplete;
	}
	
	/**
	 * Check if the given value is null or a zero-length String
	 *
	 * @param value the string to check
	 * @param errors the list of errors to append the errorMessage to if value is empty
	 * @param errorMessageCode the string with code of error message translation to append if value is
	 *            empty
	 * @return true if the value is non-empty
	 */
	private boolean checkForEmptyValue(String value, Map<String, Object[]> errors, String errorMessageCode) {
		if (!StringUtils.isEmpty(value)) {
			return true;
		}
		errors.put(errorMessageCode, null);
		return false;
	}
	
	/**
	 * Separate thread that will run through all tasks to complete the initialization. The database is
	 * created, user's created, etc here
	 */
	private class InitializationCompletion {
		
		private Thread thread;
		
		private int steps = 0;
		
		private String message = "";
		
		private Map<String, Object[]> errors = new HashMap<>();
		
		private String errorPage = null;
		
		private boolean erroneous = false;
		
		private int completedPercentage = 0;
		
		private WizardTask executingTask;
		
		private List<WizardTask> executedTasks = new ArrayList<>();
		
		public synchronized void reportError(String error, String errorPage, Object... params) {
			errors.put(error, params);
			this.errorPage = errorPage;
			erroneous = true;
		}
		
		public synchronized boolean hasErrors() {
			return erroneous;
		}
		
		public synchronized String getErrorPage() {
			return errorPage;
		}
		
		public synchronized Map<String, Object[]> getErrors() {
			return errors;
		}
		
		/**
		 * Start the completion stage. This fires up the thread to do all the work.
		 */
		public void start() {
			setStepsComplete(0);
			setInitializationComplete(false);
			thread.start();
		}
		
		public void waitForCompletion() {
			try {
				thread.join();
			}
			catch (InterruptedException e) {
				log.error("Error generated", e);
			}
		}
		
		protected synchronized void setStepsComplete(int steps) {
			this.steps = steps;
		}
		
		protected synchronized int getStepsComplete() {
			return steps;
		}
		
		public synchronized String getMessage() {
			return message;
		}
		
		public synchronized void setMessage(String message) {
			this.message = message;
			setStepsComplete(getStepsComplete() + 1);
		}
		
		/**
		 * @return the executingTask
		 */
		protected synchronized WizardTask getExecutingTask() {
			return executingTask;
		}
		
		/**
		 * @return the completedPercentage
		 */
		protected synchronized int getCompletedPercentage() {
			return completedPercentage;
		}
		
		/**
		 * @param completedPercentage the completedPercentage to set
		 */
		protected synchronized void setCompletedPercentage(int completedPercentage) {
			this.completedPercentage = completedPercentage;
		}
		
		/**
		 * Adds a task that has been completed to the list of executed tasks
		 *
		 * @param task
		 */
		protected synchronized void addExecutedTask(WizardTask task) {
			this.executedTasks.add(task);
		}
		
		/**
		 * @param executingTask the executingTask to set
		 */
		protected synchronized void setExecutingTask(WizardTask executingTask) {
			this.executingTask = executingTask;
		}
		
		/**
		 * @return the executedTasks
		 */
		protected synchronized List<WizardTask> getExecutedTasks() {
			return this.executedTasks;
		}
		
		/**
		 * This class does all the work of creating the desired database, user, updates, etc
		 */
		public InitializationCompletion() {
			Runnable r = new Runnable() {
				
				/**
				 * TODO split this up into multiple testable methods
				 *
				 * @see java.lang.Runnable#run()
				 */
				@Override
				public void run() {
					try {
						String connectionUsername;
						StringBuilder connectionPassword = new StringBuilder();
						ChangeLogDetective changeLogDetective = new ChangeLogDetective();
						ChangeLogVersionFinder changeLogVersionFinder = new ChangeLogVersionFinder();
						
						if (!wizardModel.hasCurrentOpenmrsDatabase) {
							setMessage("Create database");
							setExecutingTask(WizardTask.CREATE_SCHEMA);
							// connect via jdbc and create a database
							String sql;
							if (isCurrentDatabase(DATABASE_MYSQL)) {
								sql = "create database if not exists `?` default character set utf8";
							} else if (isCurrentDatabase(DATABASE_POSTGRESQL)) {
								sql = "create database `?` encoding 'utf8'";
							} else if (isCurrentDatabase(DATABASE_H2)) {
								sql = null;
							} else {
								sql = "create database `?`";
							}
							
							int result;
							if (sql != null) {
								result = executeStatement(false, wizardModel.createDatabaseUsername,
								    wizardModel.createDatabasePassword, sql, wizardModel.databaseName);
							} else {
								result = 1;
							}
							// throw the user back to the main screen if this error occurs
							if (result < 0) {
								reportError(ErrorMessageConstants.ERROR_DB_CREATE_NEW, DEFAULT_PAGE);
								return;
							} else {
								wizardModel.workLog.add("Created database " + wizardModel.databaseName);
							}
							
							addExecutedTask(WizardTask.CREATE_SCHEMA);
						}
						
						if (wizardModel.createDatabaseUser) {
							setMessage("Create database user");
							setExecutingTask(WizardTask.CREATE_DB_USER);
							connectionUsername = wizardModel.databaseName + "_user";
							if (connectionUsername.length() > 16) {
								connectionUsername = wizardModel.databaseName.substring(0, 11) + "_user"; // trim off enough to leave space for _user at the end
							}
							
							connectionPassword.append("");
							// generate random password from this subset of alphabet
							// intentionally left out these characters: ufsb$() to prevent certain words forming randomly
							String chars = "acdeghijklmnopqrtvwxyzACDEGHIJKLMNOPQRTVWXYZ0123456789.|~@#^&";
							Random r = new Random();
							StringBuilder randomStr = new StringBuilder("");
							for (int x = 0; x < 12; x++) {
								randomStr.append(chars.charAt(r.nextInt(chars.length())));
							}
							connectionPassword.append(randomStr);
							
							// connect via jdbc with root user and create an openmrs user
							String host = "'%'";
							if (wizardModel.databaseConnection.contains("localhost")
							        || wizardModel.databaseConnection.contains("127.0.0.1")) {
								host = "'localhost'";
							}
							
							String sql = "";
							if (isCurrentDatabase(DATABASE_MYSQL)) {
								sql = "drop user '?'@" + host;
							} else if (isCurrentDatabase(DATABASE_POSTGRESQL)) {
								sql = "drop user `?`";
							}
							
							executeStatement(true, wizardModel.createUserUsername, wizardModel.createUserPassword, sql,
							    connectionUsername);
							
							if (isCurrentDatabase(DATABASE_MYSQL)) {
								sql = "create user '?'@" + host + " identified by '?'";
							} else if (isCurrentDatabase(DATABASE_POSTGRESQL)) {
								sql = "create user `?` with password '?'";
							}
							
							if (-1 != executeStatement(false, wizardModel.createUserUsername, wizardModel.createUserPassword,
							    sql, connectionUsername, connectionPassword.toString())) {
								wizardModel.workLog.add("Created user " + connectionUsername);
							} else {
								// if error occurs stop
								reportError(ErrorMessageConstants.ERROR_DB_CREATE_DB_USER, DEFAULT_PAGE);
								return;
							}
							
							// grant the roles
							int result = 1;
							if (isCurrentDatabase(DATABASE_MYSQL)) {
								sql = "GRANT ALL ON `?`.* TO '?'@" + host;
								result = executeStatement(false, wizardModel.createUserUsername,
								    wizardModel.createUserPassword, sql, wizardModel.databaseName, connectionUsername);
							} else if (isCurrentDatabase(DATABASE_POSTGRESQL)) {
								sql = "ALTER USER `?` WITH SUPERUSER";
								result = executeStatement(false, wizardModel.createUserUsername,
								    wizardModel.createUserPassword, sql, connectionUsername);
							}
							
							// throw the user back to the main screen if this error occurs
							if (result < 0) {
								reportError(ErrorMessageConstants.ERROR_DB_GRANT_PRIV, DEFAULT_PAGE);
								return;
							} else {
								wizardModel.workLog.add("Granted user " + connectionUsername + " all privileges to database "
								        + wizardModel.databaseName);
							}
							
							addExecutedTask(WizardTask.CREATE_DB_USER);
						} else {
							connectionUsername = wizardModel.currentDatabaseUsername;
							connectionPassword.setLength(0);
							connectionPassword.append(wizardModel.currentDatabasePassword);
						}
						
						String finalDatabaseConnectionString = wizardModel.databaseConnection.replace("@DBNAME@",
						    wizardModel.databaseName);
						
						finalDatabaseConnectionString = finalDatabaseConnectionString.replace("@APPLICATIONDATADIR@",
						    OpenmrsUtil.getApplicationDataDirectory().replace("\\", "/"));
						
						// verify that the database connection works
						if (!verifyConnection(connectionUsername, connectionPassword.toString(),
						    finalDatabaseConnectionString)) {
							setMessage("Verify that the database connection works");
							// redirect to setup page if we got an error
							reportError("Unable to connect to database", DEFAULT_PAGE);
							return;
						}
						
						// save the properties for startup purposes
						Properties runtimeProperties = new Properties();
						
						runtimeProperties.put("connection.url", finalDatabaseConnectionString);
						runtimeProperties.put("connection.username", connectionUsername);
						runtimeProperties.put("connection.password", connectionPassword.toString());
						if (StringUtils.hasText(wizardModel.databaseDriver)) {
							runtimeProperties.put("connection.driver_class", wizardModel.databaseDriver);
						}
						if (finalDatabaseConnectionString.contains(DATABASE_POSTGRESQL)) {
							runtimeProperties.put("hibernate.dialect", "org.hibernate.dialect.PostgreSQL82Dialect");
						}
						if (finalDatabaseConnectionString.contains(DATABASE_SQLSERVER)) {
							runtimeProperties.put("hibernate.dialect", "org.hibernate.dialect.SQLServerDialect");
						}
						if (finalDatabaseConnectionString.contains(DATABASE_H2)) {
							runtimeProperties.put("hibernate.dialect", "org.hibernate.dialect.H2Dialect");
						}
						runtimeProperties.put("module.allow_web_admin", wizardModel.moduleWebAdmin.toString());
						runtimeProperties.put("auto_update_database", wizardModel.autoUpdateDatabase.toString());
						final Encoder base64 = Base64.getEncoder();
						runtimeProperties.put(OpenmrsConstants.ENCRYPTION_VECTOR_RUNTIME_PROPERTY,
						    new String(base64.encode(Security.generateNewInitVector()), StandardCharsets.UTF_8));
						runtimeProperties.put(OpenmrsConstants.ENCRYPTION_KEY_RUNTIME_PROPERTY,
						    new String(base64.encode(Security.generateNewSecretKey()), StandardCharsets.UTF_8));
						
						Properties properties = Context.getRuntimeProperties();
						properties.putAll(runtimeProperties);
						runtimeProperties = properties;
						Context.setRuntimeProperties(runtimeProperties);
						
						/**
						 * A callback class that prints out info about liquibase changesets
						 */
						class PrintingChangeSetExecutorCallback implements ChangeSetExecutorCallback {
							
							private int i = 1;
							
							private String message;
							
							public PrintingChangeSetExecutorCallback(String message) {
								this.message = message;
							}
							
							/**
							 * @see ChangeSetExecutorCallback#executing(liquibase.changelog.ChangeSet, int)
							 */
							@Override
							public void executing(ChangeSet changeSet, int numChangeSetsToRun) {
								setMessage(message + " (" + i++ + "/" + numChangeSetsToRun + "): Author: "
								        + changeSet.getAuthor() + " Comments: " + changeSet.getComments() + " Description: "
								        + changeSet.getDescription());
								float numChangeSetsToRunFloat = (float) numChangeSetsToRun;
								float j = (float) i;
								setCompletedPercentage(Math.round(j * 100 / numChangeSetsToRunFloat));
							}
							
						}
						
						if (wizardModel.createTables) {
							// use liquibase to create core data + tables
							try {
								String liquibaseSchemaFileName = changeLogVersionFinder.getLatestSchemaSnapshotFilename()
								        .get();
								String liquibaseCoreDataFileName = changeLogVersionFinder.getLatestCoreDataSnapshotFilename()
								        .get();
								
								setMessage("Executing " + liquibaseSchemaFileName);
								setExecutingTask(WizardTask.CREATE_TABLES);
								
								log.debug("executing Liquibase file '{}' ", liquibaseSchemaFileName);
								
								DatabaseUpdater.executeChangelog(liquibaseSchemaFileName,
								    new PrintingChangeSetExecutorCallback("OpenMRS schema file"));
								addExecutedTask(WizardTask.CREATE_TABLES);
								
								//reset for this task
								setCompletedPercentage(0);
								setExecutingTask(WizardTask.ADD_CORE_DATA);
								
								log.debug("executing Liquibase file '{}' ", liquibaseCoreDataFileName);
								
								DatabaseUpdater.executeChangelog(liquibaseCoreDataFileName,
								    new PrintingChangeSetExecutorCallback("OpenMRS core data file"));
								wizardModel.workLog.add("Created database tables and added core data");
								addExecutedTask(WizardTask.ADD_CORE_DATA);
								
							}
							catch (Exception e) {
								reportError(ErrorMessageConstants.ERROR_DB_CREATE_TABLES_OR_ADD_DEMO_DATA, DEFAULT_PAGE,
								    e.getMessage());
								log.warn("Error while trying to create tables and demo data", e);
							}
						}
						
						if (wizardModel.importTestData) {
							try {
								setMessage("Importing test data");
								setExecutingTask(WizardTask.IMPORT_TEST_DATA);
								setCompletedPercentage(0);
								
								try {
									InputStream inData = TestInstallUtil.getResourceInputStream(
									    wizardModel.remoteUrl + RELEASE_TESTING_MODULE_PATH + "generateTestDataSet.form",
									    wizardModel.remoteUsername, wizardModel.remotePassword);
									
									setCompletedPercentage(40);
									setMessage("Loading imported test data...");
									importTestDataSet(inData, finalDatabaseConnectionString, connectionUsername,
									    connectionPassword.toString());
									wizardModel.workLog.add("Imported test data");
									addExecutedTask(WizardTask.IMPORT_TEST_DATA);
									
									//reset the progress for the next task
									setCompletedPercentage(0);
									setMessage("Importing modules from remote server...");
									setExecutingTask(WizardTask.ADD_MODULES);
									
									InputStream inModules = TestInstallUtil.getResourceInputStream(
									    wizardModel.remoteUrl + RELEASE_TESTING_MODULE_PATH + "getModules.htm",
									    wizardModel.remoteUsername, wizardModel.remotePassword);
									
									setCompletedPercentage(90);
									setMessage("Adding imported modules...");
									if (!TestInstallUtil.addZippedTestModules(inModules)) {
										reportError(ErrorMessageConstants.ERROR_DB_UNABLE_TO_ADD_MODULES, DEFAULT_PAGE, "");
										return;
									} else {
										wizardModel.workLog.add("Added Modules");
										addExecutedTask(WizardTask.ADD_MODULES);
									}
								}
								catch (APIAuthenticationException e) {
									log.warn("Unable to authenticate as a User with the System Developer role");
									reportError(ErrorMessageConstants.UPDATE_ERROR_UNABLE_AUTHENTICATE,
									    TESTING_REMOTE_DETAILS_SETUP, "");
									return;
								}
							}
							catch (Exception e) {
								reportError(ErrorMessageConstants.ERROR_DB_IMPORT_TEST_DATA, DEFAULT_PAGE, e.getMessage());
								log.warn("Error while trying to import test data", e);
								return;
							}
						}
						
						// add demo data only if creating tables fresh and user selected the option add demo data
						if (wizardModel.createTables && wizardModel.addDemoData) {
							try {
								setMessage("Adding demo data");
								setCompletedPercentage(0);
								setExecutingTask(WizardTask.ADD_DEMO_DATA);
								
								log.debug("executing Liquibase file '{}' ", LIQUIBASE_DEMO_DATA);
								
								DatabaseUpdater.executeChangelog(LIQUIBASE_DEMO_DATA,
								    new PrintingChangeSetExecutorCallback("OpenMRS demo patients, users, and forms"));
								wizardModel.workLog.add("Added demo data");
								
								addExecutedTask(WizardTask.ADD_DEMO_DATA);
							}
							catch (Exception e) {
								reportError(ErrorMessageConstants.ERROR_DB_CREATE_TABLES_OR_ADD_DEMO_DATA, DEFAULT_PAGE,
								    e.getMessage());
								log.warn("Error while trying to add demo data", e);
							}
						}
						
						// update the database to the latest version
						try {
							setMessage("Updating the database to the latest version");
							setCompletedPercentage(0);
							setExecutingTask(WizardTask.UPDATE_TO_LATEST);
							
							String version = null;
							
							if (wizardModel.createTables) {
								version = changeLogVersionFinder.getLatestSnapshotVersion().get();
							} else {
								version = changeLogDetective.getInitialLiquibaseSnapshotVersion(DatabaseUpdater.CONTEXT,
								    new DatabaseUpdaterLiquibaseProvider());
							}
							
							log.debug(
							    "updating the database with versions of liquibase-update-to-latest files greater than '{}'",
							    version);
							
							List<String> changelogs = changeLogVersionFinder
							        .getUpdateFileNames(changeLogVersionFinder.getUpdateVersionsGreaterThan(version));
							
							for (String changelog : changelogs) {
								log.debug("applying Liquibase changelog '{}'", changelog);
								
								DatabaseUpdater.executeChangelog(changelog,
								    new PrintingChangeSetExecutorCallback("executing Liquibase changelog " + changelog));
							}
							addExecutedTask(WizardTask.UPDATE_TO_LATEST);
						}
						catch (Exception e) {
							reportError(ErrorMessageConstants.ERROR_DB_UPDATE_TO_LATEST, DEFAULT_PAGE, e.getMessage());
							log.warn("Error while trying to update to the latest database version", e);
							return;
						}
						
						setExecutingTask(null);
						setMessage("Starting OpenMRS");
						
						// start spring
						// after this point, all errors need to also call: contextLoader.closeWebApplicationContext(event.getServletContext())
						// logic copied from org.springframework.web.context.ContextLoaderListener
						ContextLoader contextLoader = new ContextLoader();
						contextLoader.initWebApplicationContext(filterConfig.getServletContext());
						
						// output properties to the openmrs runtime properties file so that this wizard is not run again
						FileOutputStream fos = null;
						try {
							fos = new FileOutputStream(getRuntimePropertiesFile());
							OpenmrsUtil.storeProperties(runtimeProperties, fos,
							    "Auto generated by OpenMRS initialization wizard");
							wizardModel.workLog.add("Saved runtime properties file " + getRuntimePropertiesFile());
							
							/*
							 * Fix file readability permissions:
							 * first revoke read permission from everyone, then set read permissions for only the user
							 * there is no function to set specific readability for only one user
							 * and revoke everyone else's, therefore this is the only way to accomplish this.
							 */
							wizardModel.workLog.add("Adjusting file posix properties to user readonly");
							if (getRuntimePropertiesFile().setReadable(false, false)
							        && getRuntimePropertiesFile().setReadable(true)) {
								wizardModel.workLog
								        .add("Successfully adjusted RuntimePropertiesFile to disallow world to read it");
							} else {
								wizardModel.workLog
								        .add("Unable to adjust RuntimePropertiesFile to disallow world to read it");
							}
							// don't need to catch errors here because we tested it at the beginning of the wizard
						}
						finally {
							if (fos != null) {
								fos.close();
							}
						}
						
						Context.openSession();
						
						if (!"".equals(wizardModel.implementationId)) {
							try {
								Context.addProxyPrivilege(PrivilegeConstants.MANAGE_GLOBAL_PROPERTIES);
								Context.addProxyPrivilege(PrivilegeConstants.MANAGE_CONCEPT_SOURCES);
								Context.addProxyPrivilege(PrivilegeConstants.GET_CONCEPT_SOURCES);
								Context.addProxyPrivilege(PrivilegeConstants.MANAGE_IMPLEMENTATION_ID);
								
								ImplementationId implId = new ImplementationId();
								implId.setName(wizardModel.implementationIdName);
								implId.setImplementationId(wizardModel.implementationId);
								implId.setPassphrase(wizardModel.implementationIdPassPhrase);
								implId.setDescription(wizardModel.implementationIdDescription);
								
								Context.getAdministrationService().setImplementationId(implId);
							}
							catch (Exception e) {
								reportError(ErrorMessageConstants.ERROR_SET_INPL_ID, DEFAULT_PAGE, e.getMessage());
								log.warn("Implementation ID could not be set.", e);
								Context.shutdown();
								WebModuleUtil.shutdownModules(filterConfig.getServletContext());
								contextLoader.closeWebApplicationContext(filterConfig.getServletContext());
								return;
							}
							finally {
								Context.removeProxyPrivilege(PrivilegeConstants.MANAGE_GLOBAL_PROPERTIES);
								Context.removeProxyPrivilege(PrivilegeConstants.MANAGE_CONCEPT_SOURCES);
								Context.removeProxyPrivilege(PrivilegeConstants.GET_CONCEPT_SOURCES);
								Context.removeProxyPrivilege(PrivilegeConstants.MANAGE_IMPLEMENTATION_ID);
							}
						}
						
						try {
							// change the admin user password from "test" to what they input above
							if (wizardModel.createTables) {
								try {
									Context.authenticate("admin", "test");
									
									Properties props = Context.getRuntimeProperties();
									String initValue = props.getProperty(UserService.ADMIN_PASSWORD_LOCKED_PROPERTY);
									props.setProperty(UserService.ADMIN_PASSWORD_LOCKED_PROPERTY, "false");
									Context.setRuntimeProperties(props);
									
									Context.getUserService().changePassword("test", wizardModel.adminUserPassword);
									
									if (initValue == null) {
										props.remove(UserService.ADMIN_PASSWORD_LOCKED_PROPERTY);
									} else {
										props.setProperty(UserService.ADMIN_PASSWORD_LOCKED_PROPERTY, initValue);
									}
									Context.setRuntimeProperties(props);
									Context.logout();
								}
								catch (ContextAuthenticationException ex) {
									log.info("No need to change admin password.", ex);
								}
							}
						}
						catch (Exception e) {
							Context.shutdown();
							WebModuleUtil.shutdownModules(filterConfig.getServletContext());
							contextLoader.closeWebApplicationContext(filterConfig.getServletContext());
							reportError(ErrorMessageConstants.ERROR_COMPLETE_STARTUP, DEFAULT_PAGE, e.getMessage());
							log.warn("Unable to complete the startup.", e);
							return;
						}
						
						try {
							// Update PostgreSQL Sequences after insertion of core data
							Context.getAdministrationService().updatePostgresSequence();
						}
						catch (Exception e) {
							log.warn("Not able to update PostgreSQL sequence. Startup failed for PostgreSQL", e);
							reportError(ErrorMessageConstants.ERROR_COMPLETE_STARTUP, DEFAULT_PAGE, e.getMessage());
							return;
						}

						
						// set this so that the wizard isn't run again on next page load
						Context.closeSession();
						
						// start openmrs
						try {
							UpdateFilter.setUpdatesRequired(false);
							WebDaemon.startOpenmrs(filterConfig.getServletContext());
						}
						catch (DatabaseUpdateException updateEx) {
							log.warn("Error while running the database update file", updateEx);
							reportError(ErrorMessageConstants.ERROR_DB_UPDATE, DEFAULT_PAGE, updateEx.getMessage());
							return;
						}
						catch (InputRequiredException inputRequiredEx) {
							// TODO display a page looping over the required input and ask the user for each.
							// 		When done and the user and put in their say, call DatabaseUpdater.update(Map);
							//		with the user's question/answer pairs
							log.warn(
							    "Unable to continue because user input is required for the db updates and we cannot do anything about that right now");
							reportError(ErrorMessageConstants.ERROR_INPUT_REQ, DEFAULT_PAGE);
							return;
						}
						catch (MandatoryModuleException mandatoryModEx) {
							log.warn(
							    "A mandatory module failed to start. Fix the error or unmark it as mandatory to continue.",
							    mandatoryModEx);
							reportError(ErrorMessageConstants.ERROR_MANDATORY_MOD_REQ, DEFAULT_PAGE,
							    mandatoryModEx.getMessage());
							return;
						}
						catch (OpenmrsCoreModuleException coreModEx) {
							log.warn(
							    "A core module failed to start. Make sure that all core modules (with the required minimum versions) are installed and starting properly.",
							    coreModEx);
							reportError(ErrorMessageConstants.ERROR_CORE_MOD_REQ, DEFAULT_PAGE, coreModEx.getMessage());
							return;
						}
						
						// TODO catch openmrs errors here and drop the user back out to the setup screen
						
					}
					catch (IOException e) {
						reportError(ErrorMessageConstants.ERROR_COMPLETE_STARTUP, DEFAULT_PAGE, e.getMessage());
					}
					finally {
						if (!hasErrors()) {
							// set this so that the wizard isn't run again on next page load
							setInitializationComplete(true);
							// we should also try to store selected by user language
							// if user wants to system will do it for him 
							FilterUtil.storeLocale(wizardModel.localeToSave);
						}
						setInstallationStarted(false);
					}
				}
			};
			
			thread = new Thread(r);
		}
	}
	
	/**
	 * Convenience method that loads the database driver
	 *
	 * @param connection the database connection string
	 * @param databaseDriver the database driver class name to load
	 * @return the loaded driver string
	 */
	public static String loadDriver(String connection, String databaseDriver) {
		String loadedDriverString = null;
		try {
			loadedDriverString = DatabaseUtil.loadDatabaseDriver(connection, databaseDriver);
			log.info("using database driver :" + loadedDriverString);
		}
		catch (ClassNotFoundException e) {
			log.error("The given database driver class was not found. "
			        + "Please ensure that the database driver jar file is on the class path "
			        + "(like in the webapp's lib folder)");
		}
		
		return loadedDriverString;
	}
	
	/**
	 * Utility method that checks if there is a runtime properties file containing database connection
	 * credentials
	 *
	 * @return
	 */
	private static boolean skipDatabaseSetupPage() {
		Properties props = OpenmrsUtil.getRuntimeProperties(WebConstants.WEBAPP_NAME);
		return (props != null && StringUtils.hasText(props.getProperty("connection.url"))
		        && StringUtils.hasText(props.getProperty("connection.username"))
		        && StringUtils.hasText(props.getProperty("connection.password")));
	}
	
	/**
	 * Utility methods that checks if the user clicked the back image
	 *
	 * @param httpRequest
	 * @return
	 */
	private static boolean goBack(HttpServletRequest httpRequest) {
		return "Back".equals(httpRequest.getParameter("back"))
		        || (httpRequest.getParameter("back.x") != null && httpRequest.getParameter("back.y") != null);
	}
	
	/**
	 * Convenience method to get custom installation script
	 *
	 * @return Properties from custom installation script or empty if none specified
	 * @throws RuntimeException if path to installation script is invalid
	 */
	private Properties getInstallationScript() {
		Properties prop = new Properties();
		
		String fileName = System.getProperty("OPENMRS_INSTALLATION_SCRIPT");
		if (fileName == null) {
			return prop;
		}
		if (fileName.startsWith("classpath:")) {
			fileName = fileName.substring(10);
			InputStream input = null;
			try {
				input = getClass().getClassLoader().getResourceAsStream(fileName);
				prop.load(input);
				log.info("Using installation script from classpath: " + fileName);
				
				input.close();
			}
			catch (IOException ex) {
				log.error("Failed to load installation script from classpath: " + fileName, ex);
				throw new RuntimeException(ex);
			}
			finally {
				IOUtils.closeQuietly(input);
			}
		} else {
			File file = new File(fileName);
			if (file.exists()) {
				InputStream input = null;
				try {
					input = new FileInputStream(fileName);
					prop.load(input);
					log.info("Using installation script from absolute path: " + file.getAbsolutePath());
					
					input.close();
				}
				catch (IOException ex) {
					log.error("Failed to load installation script from absolute path: " + file.getAbsolutePath(), ex);
					throw new RuntimeException(ex);
				}
				finally {
					IOUtils.closeQuietly(input);
				}
			}
		}
		return prop;
	}
}