PHP N-tier: Introduction N-Tier Strategy
PHP N-Tier Strategy Step By Step
Tutorial - Part 1: May be you face complicated situation in your client's
architecture. They use many technology for solve their complicated business
process. If it happen, n-tier may be possible one solution you can choice. It
this post, we begin to understanding possible N-Tier architecture.
General principle that we must
consider if wants to build N-tier application:
- Every layer must be independent physically. It doesn't
mean every layer have to exist in separated computer. But, every layer can
be distributed every where (separated computer or not).
- Each layer must transfer information only to/from
previous/next layer.
- You can change technology used in every layer without
change entire system. Example, - you want to change database layer- from
mySql to PostgreSQL.
Following sample architecture design
use 5-tier:
- Presentation GUI, do parse HTML, XHTML, WML.
- Presentation Logic do rendering process HTML, XHTML to
send using HTTP to browser. It accepts data from business logic and tie to
HTML. This process run at php at web server.
- Business Logic, manipulate and transform data. Simple,
task of this layer is fetch data from data access tier and prepare before
send to presentation logic. This process run at server that utilize XML.
- Data access tier have task to connect and retrieve data
from database.
- Data tier is aplication database such as mySQL,
PostGreSQL, and others.
PHP N-tier: Possible n-tier Application Use PHP
PHP N-Tier Strategy Step By Step
Tutorial - Part 2: In this post, we will try to design n-tier application use
PHP. This is my 5-tier design:
- Presentation GUI: Using smarty template to generate
HTML.
- Presentation Logic: PHP.
- Business Logic: Use NuSOAP.
- Data Access Tier: Using ADOdb.
- Data tier: Using mySQL.
We ever
talked about nusoap, adodb, and mysql. If you still understand about them,
please read posts about them.
PHP N-tier: Database Layer Using MySQL
PHP N-Tier Strategy Step By Step
Tutorial - Part 3: For practice, we will build simple application to show
5-tier design. We will begin from database layer. At the database layer, we use
MySQL.
Create a database, for example
"test". Then create table. This is the query:
“CREATE TABLE `books` (
`id`
INT( 11 ) NOT NULL AUTO_INCREMENT PRIMARY KEY ,`title`
VARCHAR( 255 ) NOT NULL ,`author`
VARCHAR( 60 ) NOT NULL)
ENGINE = MYISAM ;”
Next, try to insert sample data, such as:
“INSERT INTO `test`.`books` (
`id` ,
`title` ,
`author`
)
VALUES (
NULL , 'PHP Undercover', 'Wiwit Siswoutomo'
), (
NULL , 'PHP Enterprise', 'Wiwit Siswoutomo'
);
”
Ok, next post we will try how to connect database use PHP
ADOdb as data access tier.
PHP N-tier: Data Access Tier Using PHP ADOdb
PHP N-Tier Strategy Step By Step
Tutorial - Part 4: In this post, we will build data access tier. We use PHP
Adodb. About PHP Adodb, you can read at here.
For this practice, create a folder
named "ntier" within www/test. Place your all PHP ADOdb folder at
here. Thus, you have www/test/ntier/adodb.
Then create a file named
"dataaccess.php" within www/test/ntier. Enter following code
include('adodb/adodb.inc.php');
$databasetype = 'mysql';
$server = 'localhost';
$user = 'root';
$password = 'admin';
$database = 'test';
$db = ADONewConnection($databasetype);
$db->debug = false;
$db->Connect($server, $user, $password, $database);
$recordSet = &$db->Execute('select * from books');
if (!$recordSet)
print $conn->ErrorMsg();
else
while (!$recordSet->EOF) {
print $recordSet->fields[0].' '.$recordSet->fields[1].' '.$recordSet->fields[2].'
';
$recordSet->MoveNext();
}
$recordSet->Close(); # optional
$db->Close();
?>
Test it. Open your browser. point to
http://localhost/test/ntier/dataacces.php.
PHP N-tier: Building Business Logic
PHP N-Tier Strategy Step By Step
Tutorial - Part 5: After create connection to database at this
post, we will process this data. We
prepare this data in order to can to send using webservices. We named this:
business logic layer.
This practice only work well for php
4. In php 5, we will talk next serial post. Because there is embedded function
in php 5. First, copy library of nusoap within www/test/ntier/lib. If you don't
understant to place nusoap, please read this
post.
Open again file dataacces.php within
www/test/ntier. Update like following:
// call library
require_once ( './lib/nusoap.php' ); //nusoap
require_once ('adodb/adodb.inc.php');//adodb
// create instance
$server = new soap_server();
// initialize WSDL support
$server->configureWSDL( 'hello' , 'urn:hellowsdl' );
// place schema at namespace with prefix tns
$server->wsdl->schemaTargetNamespace = 'urn:hellowsdl';
// register method
$server->register('books', // method name
array(), // input parameter
array('return'=>'xsd:array'),
'urn:hellowsdl' , // namespace
'urn:hellowsdl#hello', // soapaction
'rpc', // style
'encoded', // use
'Load list of book to the caller' // documentation
);
// configuration database
define(__databasetype__,'mysql');
define(__server__,'localhost');
define(__user__,'root');
define(__password__,'admin');
define(__database__,'test');
// method
function books(){
$db = ADONewConnection(__databasetype__);
$db->debug = false;
$db->Connect(__server__, __user__, __password__, __database__);
$recordSet = &$db->Execute('select * from books');
if (!$recordSet){
return new soap_fault('Server','',$conn->ErrorMsg());
} else {
while (!$recordSet->EOF) {
$books[] = array('id'=>$recordSet->fields[0],
'title'=>$recordSet->fields[1],
'author'=>$recordSet->fields[2]
);
$recordSet->MoveNext();
}
$recordSet->Close(); #optional
$db->Close();
}
// return value to client
$obj = new soapval('return','array',$books);
return $obj->serialize();
}
$HTTP_RAW_POST_DATA = isset($HTTP_RAW_POST_DATA) ? $HTTP_RAW_POST_DATA : '';
$server->service($HTTP_RAW_POST_DATA);
?>
Then, test it. Open your browser. Point to
http://localhost/test/ntier/dataacces.php. You will get like this:
PHP N-tier: Building Presentation Logic
PHP N-Tier Strategy Step By Step Tutorial - Part 6: After create business
logic, now we try to catch the data. We called this: presentation logic layer.
We still use nusoap to do this job.
Just for practice, we will create
client same folder/location with server function. Create a file named
"client_book.php" within www/test/ntier. Enter following code:
require_once ('lib/nusoap.php');
$client = new soapclient('http://localhost/test/ntier/dataacces.php');
$response = $client->call('books');
if($client->fault)
{
echo "FAULT: Code: (".$client->faultcode.")
";
echo "String: ".$client->faultstring;
}
else
{
$r = $response[0];
$count = count($r);
?>
Id |
Title |
Author |
|---|
for($i=0;$i<=$count-1;$i++){
?>
|
|
|
}
?>
}
?>
PHP N-tier: Building Presentation GUI
PHP N-Tier Strategy Step By Step
Tutorial - Part 7: We have grabbed data from server at presentation logic. And
we tie data to html at previous post. It will give us more flexible if we you
template system. So, we can change any layout without change all. for this job,
we use smarty template.
Exactly, what is smarty template? I
rewrite from their readme: Smarty is a template engine for PHP. Many other
template engines for PHP provide basic variable substitution and dynamic block
functionality. Smarty takes a step further to be a "smart" template
engine, adding features such as configuration files, template functions, and
variable modifiers, and making all of this functionality as easy as possible to
use for both programmers and template designers.
First, please download smarty
template at smarty.php.net. Extract compressed file to www/test/ntier. You will
get folder named like "smarty-2.6.xx". Rename, for simply, become:
"smarty".
Then, create folders named
"templates" and "templates_c" within www/test/ntier.
Open again your client_book.php,
rewrite with this code:
// call library
require_once ('./lib/nusoap.php');
require_once ('./smarty/libs/smarty.class.php');
// retrieve data from server
// use webservice by nusoap
$client = new soapclient('http://localhost:8048/test/ntier/dataacces.php');
$response = $client->call('books');
if($client->fault)
{
echo "FAULT: Code: (".$client->faultcode.")
";
echo "String: ".$client->faultstring;
die();
}
else
{
// start using smarty
$smarty = new Smarty;
// assign parameters
$smarty->assign("title","Books Collection");
$smarty->assign("books",$response[0]);
//load template
$smarty->display('template.tpl');
}
?>
Now, you can see. Your code be more
clean. No html tag over there. All html tag will be place at template.
Create a file named
"template.tpl" within www/test/ntier/templates. Then enter following
code:
{$title}
Id |
Title |
Author |
|---|
{foreach key=key item=item from=$books}
{foreach key=key item=item from=$item}
{$item} |
{/foreach}
{/foreach}
Congrat! you have understand how to build 5-tier use php.
You can expand this tutorial as you need.
