node-proc/index.js

Module to access Linux /proc information

#!/usr/bin/env node
/**
 * Node Proc Pseudo-Filesystem Reader
 *
 * @package     Node-Proc
 * @subpackage  Index
 *
 * @author James Cunningham <tetrauk@gmail.com>
 * @copyright Copyright 2013 James Cunningham.
 */

/*	--- Dependencies ---
	-------------------------------------------------- */

	var FS = require( 'fs' );



/*	--- Filesystem Access Functions ---
	-------------------------------------------------- */

	/**
	 * Read Proc File
	 *
	 * @param   string    filename  Proc Filename (excluding /proc)
	 * @param   function  callback  Callback( object err, string filedata )
	 * @return  void
	 */
	function readProcFile( filename, callback )
	{
		FS.readFile( '/proc/'+filename, function( err, filedata )
		{
			if ( err ) return callback( err );

			return callback( null, filedata.toString() );
		});
	}

	// Export Function
	exports.read = readProcFile;


	/**
	 * Read KeyValue String
	 *
	 * @param   string  input  Input String
	 * @param   stirng  sep    Seperator (default ":")
	 */
	function readKeyValue( input, sep )
	{
		if ( !sep ) sep = ":";

		input = input.trim().split( "\n" );

		var r = {};

		for( key in input )
		{
			line = input[ key ].trim().split( sep );

			if ( line.length != 2 ) continue;

			line[0] = line[0].trim();
			line[1] = line[1].trim();

			// Convert kB values to bytes
			if ( line[1].slice( -3 ) == ' kB' || line[1].slice( -3 ) == ' KB' )
				line[1] = parseInt( line[1].substr( 0, line[1].length -3 ) ) * 1024;

			// Append To Response
			r[ line[0] ] = line[1];
		}

		return r;
	}



/*	--- Memory Information ---
	-------------------------------------------------- */

	/**
	 * Memory Info
	 *
	 * @param   function  callback( object err, array meminfo )
	 * @return  void
	 */
	exports.meminfo = function( callback )
	{
		readProcFile( 'meminfo', function( err, meminfo )
		{
			if ( err ) return callback( err );

			meminfo = readKeyValue( meminfo );

			return callback( null, meminfo );
		});
	};


/*	--- CPU Information ---
	-------------------------------------------------- */

	/**
	 * CPU Info
	 *
	 * @param   function  callback( object err, array cpuinfo )
	 * @return  void
	 */
	exports.cpuinfo = function( callback )
	{
		readProcFile( 'cpuinfo', function( err, cpuinfo )
		{
			if ( err ) return callback( err );

			// Split Multiple Processors
			var procs = cpuinfo.split("\n\n");

			var r = [];

			// Format Each Processor
			for( p in procs )
			{
				if ( procs[p].length < 1 ) continue;

				// Parse and append to response
				r.push( readKeyValue( procs[p] ) );
			}

			return callback( null, r );
		});
	};



/*	--- Network Functions ---
	-------------------------------------------------- */

	/**
	 * Network Devices Transfer
	 *
	 * @param   function  callback( object err, array netdev )
	 * @return  void
	 */
	exports.netdev = function( callback )
	{
		readProcFile( 'net/dev', function( err, netdev )
		{
			if ( err ) return callback( err );

			netdev = netdev.trim().split( "\n" );

			// Remove Headers
			netdev.shift(); netdev.shift();

			var r = [];

			for( dev in netdev )
			{
				// Split Line by whitespace
				line = netdev[dev].trim().match( /\S+/g );

				// Append To Response
				r.push({
					device: line[0].substr( 0, line[0].length - 1 ),
					Rx: {
						bytes: line[1],
						packets: line[2]
					},
					Tx: {
						bytes: line[9],
						packets: line[10]
					}
				});
			}

			return callback( null, r );
		});
	};



/*	--- System Time ---
	-------------------------------------------------- */

	/**
	 * Uptime
	 *
	 * @param   function  callback( object err, integer uptime, integer startTime )
	 * @return  void
	 */
	exports.uptime = function( callback )
	{
		readProcFile( 'uptime', function( err, uptime )
		{
			if ( err ) return callback( err );

			uptime = uptime.split( ' ' );
			uptime = parseInt( uptime[0].split('.')[0] );

			var startTime = Math.floor(new Date().getTime() / 1000) - uptime;

			return callback( null, uptime, startTime );
		});
	};