Ecosyste.ms: Awesome

An open API service indexing awesome lists of open source software.

Awesome Lists | Featured Topics | Projects

https://github.com/msakrejda/pegasus

An ActionScript 3 driver for PostgreSQL.
https://github.com/msakrejda/pegasus

Last synced: 11 days ago
JSON representation

An ActionScript 3 driver for PostgreSQL.

Awesome Lists containing this project

README 

        
Pegasus

^^^^^^^



An ActionScript 3 driver for the PostgreSQL open source database.



Overview

~~~~~~~~



Pegasus currently supports both the simple and extended query

protocols, clear-text, md5 hashed, and trust authentication, and the

PostgreSQL notification mechanism (LISTEN/NOTIFY). It has an

extensible data type handling system with built-in support for the

most common types (Date, Number, int, Boolean, and String in

ActionScript, and their PostgreSQL equivalents).



The pegasus core library can be used in plain Flash stand-alone

applications, Flash web applications, and Flex or AIR applications

(albeit the Flash cross-domain policies will prevent you from doing

anything too colorful from a web app).



The pegasus repository includes pgconsole, a simple AIR application

which can connect to a PostgreSQL server, issue queries, and display

results. It also supports notifications (i.e., you can issue a LISTEN

and get notifications of the corresponding NOTIFY events).



Example

~~~~~~~



Here is an example of pegasus usage:: 



    // Create a ConnectionFactory

    var connFactory:ConnectionFactory = new ConnectionFactory();



    // Pegasus uses jdbc-like URLs for configuring host, port, and target database

    // as well as for connection properties (not shown)

    var url:String = 'asdbc:postgresql://localhost:5432/postgres';

    var user:String = 'postgres';

    var password:String = 'postgres';

    var conn:IConnection = connFactory.createConnection(url, user, password);



    // Add event listeners. The actual functions are omitted; they are fairly

    // straightforward event handlers. Note that the NoticEvent.ERROR handler

    // is the mechanism for communicating query errors, so be sure to listen

    // for at least these events

    conn.addEventListener(NoticeEvent.NOTICE, handleNotice);

    conn.addEventListener(NoticeEvent.ERROR, handleError);

    conn.addEventListener(ParameterChangeEvent.PARAMETER_CHANGE, handleParamChange);

    conn.addEventListener(NotificationEvent.NOTIFICATION, handleNotification);

    conn.addEventListener(ConnectionEvent.CONNECTED, handleConnected);

    conn.addEventListener(ConnectionErrorEvent.CONNECTIVITY_ERROR, handleConnectivityError);

    conn.addEventListener(ConnectionErrorEvent.PROTOCOL_ERROR, handleProtocolError);

    conn.addEventListener(ConnectionErrorEvent.CODEC_ERROR, handleCodecError);



    // Each query needs a result handler. Pegasus comes with two types of result handlers,

    // or you can write your own. A result handler needs to respond to results from

    // the query (if any) and to successful query completion. The EventResultHandler dispatches

    // events when results are available and when the query completes.

    var handler:IResultHandler = new EventResultHandler();

    // Add a handler for query results; you can often ignore completion

    IEventDispatcher(handler).addEventListener(QueryResultEvent.RESULT, handleResult);

    // Parameter markers use standard PostgreSQL syntax. Parameter input

    // mappings (from ActionScript data types to PostgreSQL types) are

    // configurable, but defaults are sensible for simple use cases.

    conn.execute(handler, "select 'hello ' || $1", [ 'world' ]);



This is a sample result handler::



    function handleResult(event:QueryResultEvent):void {

    	trace("Columns are:");

        for (var col:IColumn in event.columns) {

	    trace('Column', col.name, col.type);

	}

	trace("Data is:");

	// PostgreSQL data types are automatically mapped to corresponding

	// ActionScript data types (the mappings can be reconfigured, but

	// again, the defaults are sensible for simple uses)

	for (var row:Object in event.data) {

	    for (var col:IColumn in event.columns) {

	    	trace("Value for column", col.name, "is", row[col.name]);

	    }

	}

    }



A more extensive example is available in `pgconsole`. Asdoc API

documentation is also available.