Running Jaxer with MySQL

Changing the Database Configuration Settings

To run Jaxer with the mysql database it is just a matter of making a very simple change, to a single file
<INSTALL FOLDER>/local_jaxer/config.js

As shipped this file contains a set of common configuration overrides, but they are all commented out. The file is a simple JS function that updates a set of property values on the Config object. The source for this file is shown below

uncomment lines 33-43 if you only want to use MYSQL for your application data

uncomment lines 44-54 if you only want to use MYSQL for the jaxer server metadata

uncomment lines 33-54 if you want to use MYSQL for both application data and server metadata

Once you have uncommented the lines you need to provide the connection parameters for your MYSQL instance.

The Config.DB_CONNECTION_PARAMS / Config.DB_FRAMEWORK_CONNECTION_PARAMS objects have properties for

HOST : the ip address or uri for the server
PORT : the port the server is running on (typically 3306 for MYSQL)
NAME : the name of the database to use
USER : user name
PASS : password

Set these value to match your database. Then restart Jaxer to load the changes, your Jaxer instance will now be running with MYSQL

After the changes the config file will look something like this.

/* 
 * Use this file to override the default configuration settings.
 * This file is read right after the default config.js is read
 * but before anything else is done, so you can override anything you need.
 * Since these only gets read at server startup, you'll need to restart Jaxer
 * after modifying this file for those modifications to have an effect.
 */
(function(){

// Use the following to override where some of your local overrides are located:
//	Config.LOCAL_CONFIG_LOG = 		"../local_jaxer/conf/configLog.js";
//	Config.LOCAL_CONFIG_ROUTES = 	"../local_jaxer/conf/configRoutes.js";
//	Config.LOCAL_EXTENSIONS_DIR = 	"../local_jaxer/extensions";
	
	// Use the following to override some of the default error-handling settings:
//	Config.UNCAUGHT_ERRORS_ARE_RESPONSE_ERRORS = true;
//	Config.INCLUDE_ERRORS_ARE_RESPONSE_ERRORS = true;
//	Config.RESPONSE_ERROR_PAGE = "resource:///content/responseError.html"; 
//	Config.FATAL_ERROR_PAGE = "resource:///content/fatalError.html";
//	Config.CALLBACK_ERROR_MESSAGE = "Error on server during callback - further information has been logged";
//	Config.CALLBACK_FATAL_ERROR_MESSAGE = "Callback could not be processed due to server error - further information has been logged";
//	Config.DISPLAY_ERRORS = true; // set to true only in development/debug stage: some error messages may be displayed within the served page or in callbacks
//	Config.ALERT_CALLBACK_ERRORS = true; // whether to popup a window.alert(...) when a callback returns an error
	
	// To include scripts and access files and so on, Jaxer may need to get that content from the web server.
	// If your web server needs to be reached via a different domain/port than the incoming request,
	// uncomment and change the following to replace the protocol://domain:port with this value
//	Config.REWRITE_RELATIVE_URL = "http://192.168.0.1:8082"; // If your web server is reachable at IP 192.168.0.1 on port 8082
//	Config.REWRITE_RELATIVE_URL_REGEX = "^http\\:\\/\\/my.domain.com"; // Optional -- if e.g. you only want to replace URLs that start with this

// To have Jaxer use MySQL rather than SQLite, for its own needs or your applications or both,
	// use settings similar to the following:
	Config.DB_IMPLEMENTATION = "MySQL";
	Config.DB_CONNECTION_PARAMS =
	{
		HOST: "127.0.0.1",
		PORT: 4417,        // This uses a port different than the default of 3306, to minimize conflicts with existing installs
		NAME: "myApplicationDB",
		USER: "root",
		PASS: "",
		CLOSE_AFTER_EXECUTE: false,
		CLOSE_AFTER_REQUEST: true
	};
	Config.DB_FRAMEWORK_IMPLEMENTATION = "MySQL";
	Config.DB_FRAMEWORK_CONNECTION_PARAMS =
	{
		HOST: "127.0.0.1",
		PORT: 4417,        // This uses a port different than the default of 3306, to minimize conflicts with existing installs
		NAME: "jaxerFrameworkDB",
		USER: "root",
		PASS: "",
		CLOSE_AFTER_EXECUTE: false,
		CLOSE_AFTER_REQUEST: true
	};

// To embed the client part of the Jaxer framework in the web page, 
	// specify its location in EMBEDDED_CLIENT_FRAMEWORK_SRC
	// Alternatively, to have the web server serve its contents, 
	// 1) comment out EMBEDDED_CLIENT_FRAMEWORK_SRC,
	// 2) copy the client framework to somewhere the web server can reach it, and
	// 3) use CLIENT_FRAMEWORK_SRC to specify the src of the <SCRIPT> element that will be inserted into the page
//	Config.EMBEDDED_CLIENT_FRAMEWORK_SRC = "resource:///framework/clientFramework_compressed.js";
//	// Config.CLIENT_FRAMEWORK_SRC = "/aptana/clientFramework.js";
	
	// If you are modifying the Jaxer framework, you may want to use the modified copy, so you
	// can quickly test out your modifications. Here's how (replace <...> with the right values:
//	var depotDir = "file:///C:/Documents and Settings/<username>/My Documents/Aptana Studio/<framework_project>";
//	var depotConfigPath = depotDir + "/config.js";
//	// Get the latest config settings from the local depot copy, not the install directory
//	Jaxer.include(depotConfigPath);
//	// But the depot's config will point back to the install directory, so override that explicitly
//	Config.FRAMEWORK_DIR = depotDir;

})();

Creating a Connection to a MySQL db.

For many applications you wont want to use the built-in jaxer DB instance definitions and will require a dedicated connection to another instance or perhaps a separate database on the same instance.

The code below is an example of how to create and use a connection to a database.

/*
 * The following example shows how to connect to MySQL DB and how to run a query against it
 */

// First we need to create a connection object
 	var myConnection = new Jaxer.DB.MySQL.Connection({
    	'HOST': 'localhost',
    	'PORT': 3306,
    	'USER': 'root',
    	'PASS': 'mySQL',
    	'NAME': 'users',
    	'CLOSE_AFTER_EXECUTE': false //this parameter is optional, default value is false
	});
	
// define a query and execute
	var query = "select * from table_name";
	var queryResult = myConnection.execute(query);
	
// query result is an object type of Jaxer.DB.ResultSet

/*
 * The following example demonstrates how to extract data from Jaxer.DB.ResultSet object
 * based on the given columns
 * 
 */

//Let's assume we have a table in the database, which contains user information, i.e. first
//and last names, SSN, DOB, address and so on. 
  
//Using sample that describes how to connect to DB and run query against it, let's run
//the follwing query

var myQueryResultSet = myConnection.execute("SELECT * FROM users");

//Result of the query is stored in object myQueryResultSet, which is type of Jaxer.DB.ResultSet
//Now we need to extract data based on the given columns, for instance, first and last names.
//In order to do so, we need to build an array of columns to be extracted, which will be used
//as an input parameter for extractColumns() method

var columnsToExtract = ["FirstName", "LastName"];
 
//In this array, each element is the column name, for which we want to extract data
//If you need to extract data for all columns ycan get array of the columns using following 
//propery:
//var tableColumns = myQueryResultSet.columns;
//Now we can call extractColumns() method

var extractedColumnsData = myQueryResultSet.extractColumns(columnsToExtract);

//The return value of this method is an array of objects, one per row, that only have properties 
//corresponding to the given columns.
//Here is how we can access specific cell from returned array

//var cellValue = extractedColumnsData[<nRow>].<colName>

//where nRow is a row number and colName is name of the column
//So if I need to get first and last names from first row than here is what I need to do

var fName = extractedColumnsData[0].FirstName;
 var lName = extractedColumnsData[0].LastName;
 
 // print values to the log file
 Jaxer.Log.info("First Name is: " + fName);
 Jaxer.Log.info("Last Name is: " + lName);

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