Abstraction Layers
|
|
|
|
<?PHP
/*************************
Author: Simon Johnson
Date: 01/07/2002
**************************/
/*************************
This class was written specifically for my needs, acts as an abstraction,
to separate database connectivity from application logic, returns very little in the way of output,
unless specified in the query method - Nice formatted table(Easy reference), Do not use as output, just
a guide, the table is poor for large datasets!
I didnt want textual output everywhere,so have used logs to display relavent info,
alot more graceful! PLEASE REMEBER TO SET REQUIRED FILE PERMISSIONS ON SERVER FOR LOGS.
YOU MUST HAVE ROOT ACCESS TO ALLOW AUTO CREATE OF LOGS
*************************/
/*************************
PRIVATE: Private attributes not supported in php, so
leave out get accessors where this key word is. You cen enforce change using
set if required
**************************/
/*TODO: Create separate file writer object for error handling*/
/*TODO: Support transactions and pointers.+better rows handlers*/
class Dbase
{
//CLASS ATTRIBUTES
/*************
If you want to explicitly set connection details do so below
************/
var $hostname;
var $username;
var $password;
var $dbname;
/*****************************************
To turn error and action reporting on, set to one, else leave blank.
If it is set on, create a directory /logs, in the same filesystem as the class.
Create two files, action_log.txt and dbase_log.txt.
*******************************************/
var $err_rep=1;
var $dbtype;
var $qryrows;
var $qryfields;
var $tblname;
var $error;
var $conn; //PRIVATE
var $action;
var $querystring;
var $qryresult;
var $try; //PRIVATE
/*******************************************
FULL SET OF ACCESSOR METHODS TO ENCOURAGE ENCAPSULATION AND DATA HIDING
********************************************/
/*******
SETTERS
********/
function setDbname($newdbname)
{
$this->dbname=$newdbname;
}
function setTry($newtry)
{
$this->try=$newtry;
}
function setDbtype($newdbtype)
{
$this->dbtype=$newdbtype;
}
function setHostname($newhostname)
{
$this->hostname=$newhostname;
}
function setUsername($newusername)
{
$this->username=$newusername;
}
function setPassword($newpassword)
{
$this->password=$newpassword;
}
function setQryrows($newqryrows)
{
$this->qryrows=$newqryrows;
}
function setQryfields($newqryfields)
{
$this->qryfields=$newqryfields;
}
function setTblname($newtblname)
{
$this->tblname=$newtblname;
}
function setError($newerror)
{
$this->error=$newerror;
$date = date("j m Y");
if ($this->err_rep=="1")
{
$filelocation="dbase_log.txt";
$newfile = fopen($filelocation,"a+");
$add = "n"."$this->error: $date";
fwrite($newfile, $add);
fclose($newfile);
}
else
{
//Do nothing
}
}
function setConn($newconn)
{
$this->conn=$newconn;
}
function setAction($newaction)
{
$this->action=$newaction;
$date = date("G:i : j m Y");
if ($this->err_rep=="1")
{
$filelocation="action_log.txt";
$newfile = fopen($filelocation,"a+");
$add = "n"."$this->action: $date";
fwrite($newfile, $add);
fclose($newfile);
}
else
{
//Do nothing - This needs addressing, not brilliant coding!
}
}
function setQuerystring($newquerystring)
{
$this->querystring=$newquerystring;
}
function setQryresult($newqryresult)
{
$this->qryresult=$newqryresult;
}
function setErr_rep($newerr_rep)
{
$this->err_rep=$newerr_rep;
}
/********
GETTERS
********/
function getDbname()
{
return $this->dbname;
}
function getDbtype()
{
return $this->dbtype;
}
function getHostname()
{
return $this->hostname;
}
function getUsername()
{
return $this->username;
}
function getPassword()
{
return $this->password;
}
function getQryrows()
{
return $this->qryrows;
}
function getQryfields()
{
return $this->qryfields;
}
function getTblname()
{
return $this->tblname;
}
function getError()
{
return $this->error;
}
function getAction()
{
return $this->action;
}
function getQuerystring()
{
return $this->querystring;
}
function getQryresult()
{
return $this->qryresult;
}
function getErr_rep()
{
return $this->err_rep;
}
/******************************
OPERATOR FUNCTIONS
******************************/
function SetUp($hostname,$username,$password,$dbname)
{
/*******************************
INCASE SOMETHING GOES WRONG WITH FILE WRITER, CHECK LOG SET-UP
********************************/
if ($this->err_rep==1)
{
if (file_exists("action_log.txt"))
{
$this->setAction("NEW INSTANCE");
}
else
{
echo"No files Found, first run detected, attempting to create log files, re-instantiate object for populated firstrun logs";
}
}
else
{}
$this->setHostname($hostname);
$this->setUsername($username);
$this->setPassword($password);
$this->setDbname($dbname);
}
function Connect($type)//THIS PARAMETRE IS REQUIRED!! EITHER 1 or 0
/*****************
Will return a message if theres an error, get the message in the child
like so: '$message=$con->Connect()'
Or use the accessor '$message=$con->GetError()', or just check the log!
********************/
{
if(($this->username=="")||($this->password=="")||($this->hostname==""))
{
$this->setError("You have failed to insert either your' username, hostname or password");
}
else
{
switch($type)
{
case "1":
$this->conn = @mysql_pconnect($this->hostname,$this->username,$this->password);
break;
default:
$this->conn = @mysql_connect($this->hostname,$this->username,$this->password);
break;
}
if ($this->conn)
{
$this->setAction("Connection Made to Database on $this->hostname");
$this->setTry(mysql_select_db($this->dbname));
if($this->try)
{
$this->setAction("Successfully communicating with database: $this->dbname");
}
else
{
$this->setAction("Connection made but cannot talk to database");
$this->setError("This certainly shouldn't happen!!");
}
}
else
{
$this->setAction("Database Connection Attempt Failed See Error log");
$this->setError("Database Connection Error,reason: Connection remains in scope");
}
}return $this->error;
}
function Disconnect()
{
if($this->conn)
{
$this->try=mysql_close($this->conn);
$this->setConn(mysql_free_result($this->qryresult));
if($this->try)
{
$this->setAction("Database Connection closed");
}
else
{
$this->setAction("Attempted to close Database Connection however it is Persistant");
$this->setError("Database Remains Open");
}
}
else
{
$this->setAction("Database connection could not be made, so disconnection is irrelavent");
$this->setError("Database Remains Closed");
}
}
function Query($string, $display)
{
if($this->conn)
{
$this->setQuerystring($string);
$this->setQryresult(mysql_db_query($this->dbname, $this->querystring));
$this->setQryrows(mysql_num_rows($this->qryresult));
$this->setQryfields(mysql_num_fields($this->qryresult));
if($this->qryresult)
{
$this->setAction("Query Execution Success");
if ($display=="1")
{
$this->setAction("Attempting to display query results");
$c=$this->qryfields;
$r=$this->qryrows;
echo"<table border=1><tr>";
for ($i = 0; $i < $c; $i++)
{
$cols = mysql_field_name($this->qryresult, $i);
$cols=strtoupper($cols);
echo "<td border=1><b><font face=arial size=1>$cols</b><br>";
for ($g = 0; $g < $r; $g++)
{
$rows = mysql_result($this->qryresult, $g, $cols);
echo "<font face=arial size=1><br>$rows<br><br>";
}
}
echo"</font></table>";
}
else
{
$this->setAction("No Display of query requested, populating result resource");
}
}
else
{
$this->setAction("Query Execution Failure");
$this->setError("Query Execution Error");
}
}
else
{
$this->setAction("Credentials could not be verified or connection instance not called");
$this->setError("Bad credentials or connection instance not called");
}
}
}
?>
|
|
|
Usage Example
|
<?
require("dbase.class.php");
$con = new Dbase();
$con -> SetUp("Localhost","Username","password","shop");
$con -> Connect();
$string= "select * from shop";
/*Adding the 1 as the second parameter,
automatically returns a formatted table.
*/
$con -> Query($string,1);
$result=$con->getQryresult();
$numOfRows=$con->getQryrows();
$con->Disconnect();
?>
|
|
|
Rate This Script
|
|
|
|
Store
Your email: