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Posts tagged PHP
Simple Zend Framework and Ajax Tutorial
Mar 3rd
I love the Zend Framework. I’ve been using it since version 1.5 (currently at 1.10 as of this writing). It has so many features and can do so many things–sometimes it’s just not immediately clear how to implement those great features.
One feature that took me awhile to figure out was AJAX context switching. The documentation contains various pieces of information about implementing AJAX, but it just wasn’t clear how to put those pieces together. To help make this more clear, I’m going to go through a simple example of how to add very basic AJAX to the Zend Framework QuickStart project. I’m going to be using jQuery because I prefer that to Dojo and the rest of the JavaScript frameworks.
This tutorial assumes you already have a development server set up, Zend Framework installed, and the Zend Framework QuickStart project up and running.
Modify IndexController.php
First we need to set up Ajax context switching in the main controller. Add the following init() function to the index controller found in controllers/IndexController.php
public function init()
{
$ajaxContext = $this->_helper->getHelper('AjaxContext');
$ajaxContext->addActionContext('list', 'html')
->addActionContext('modify', 'html')
->initContext();
}
The html parameter is the type of Ajax request. You can also use JSON or XML.
Note: The modify context is not used in this tutorial but is merely there to demonstrate that you can have as many action contexts as you want.
Now we need to add the list action that we specified above in the addActionContext call to the IndexController.php.
public function listAction() {
// pretend this is a sophisticated database query
$data = array('red','green','blue','yellow');
$this->view->data = $data;
}
Create the list view scripts
By default, Zend Framework tries to render view scripts with the same name as the action. If our action’s name is list and is controlled by the controller named index, then Zend will try to render a view script located at view/scripts/index/list.phtml. Since we are using Ajax context switching, Zend Framework attempts to render view/scripts/index/list.ajax.phtml instead.
For testing my Ajax actions I usually create a normal view helper as well as the Ajax helper but then just include the Ajax view helper.
Create the following view scripts. The second script list.phtml is optional but might aid in troubleshooting.
views/scripts/index/list.ajax.phtml
<!-- views/scripts/list.ajax.phtml should contain something like the following --> <ul> <?php foreach ($this->data as $color) : ?> <li><?= $color ?></li> <?php endforeach; ?> </ul>
views/scripts/index/list.phtml
<?php
include('list.ajax.phtml');
jQuery time
The last thing we need to do is to add some HTML and JavaScript to our index.phtml view script to test everything out.
Add the following to the bottom of views/scripts/index/index.phtml
<div id="container">
</div>
<script type="text/javascript">
$(document).ready(function() {
$('#container').load('/default/index/list/format/html');
});
</script>
The most important part of that jQuery code is the content of the URL you specify. This is one of those cases when you need to specify the module and controller and action even if they are set to the default value.
‘/module/controller/action/format/html’
You must also not forget the format/html part. If you forget it, you’ll notice that Zend is rendering your layout too instead of just rendering the view script.
That’s it. You should now have a list of colours on the first page of your site.
UPDATE: there was an error in the jQuery code on the index.phtml view script. The code is correct now. I have also added a working project to my Google Code repository. Thanks to the commenters for pointing this out.
Configuring Zend Server CE in Ubuntu 9.10 on a Rackspace Cloud Server
Feb 15th
Overview
This guide will help you set up the following:
- Zend Server CE (Apache/PHP)
- Iptables
- SSH
- MySQL
- Postfix (for outgoing mail)
Some of these steps are taken from the Rackspace Cloud Server Knowledgebase.
Create a new server instance
Log in to http://manage.rackspacecloud.com and create a new server instance with Ubuntu 9.10. Any instance size is great. I’d recommend naming your server with your FQDN as it saves a few changes later on.
Securing the server
The Rackspace Cloud Server comes with the root account enabled and no firewall setup. This is not a good thing for a public server. So the first thing we will do is create a new administrator account which we will use to log in via SSH, and then we will set up Iptables as our firewall.
Rackspace will email you the IP address and password of your new server instance.
Log in over SSH to your server instance. If you have a Mac just open a terminal window and enter something like the following:
ssh root@your_server_ip
If you use windows download putty, enter the IP address in the host box and click connect.
You should now be logged in to your new Cloud Server.
The first thing we are going to do is change the root password.
Change the password by using:
passwd
Since we don’t want to log in as root anymore, we need to create a new user.
adduser admin
We want the admin user to be able to become a super user so we need to add admin to the visudo file by entering this:
visudo
Nano will open a file; add the following to the bottom of the file.
admin ALL=(ALL) ALL
Next we will make some changes to the SSH configuration file. It is also a good idea to change the port SSH uses for security. We will also disable root logins and enable admin to log in via SSH.
nano /etc/ssh/sshd_config
Port 54321 PermitRootLogin no X11Forwarding no UsePAM no UseDNS no AllowUsers admin
To make those changes take effect, restart SSH. You will not be disconnected, but if you do disconnect, you will need to reconnect using your new username and new port.
/etc/init.d/ssh restart
Firewall Configuration
This server will be a web host so very few ports will be opened.
- HTTP 80
- HTTPS 443
- HTTP 10081 (Zend Server CE)
- SSH 54321
All other ports are dropped.
Create a file named iptables.test.rules in /etc and open it using nano.
nano /etc/iptables.test.rules
Add the file lines to that file. Make changes where required.
* filter :INPUT DROP [1:48] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [129:20352] # Allows all loopback (lo0) traffic and drop all traffic to 127/8 that doesn't -A INPUT -i lo -j ACCEPT -A INPUT -i ! lo -d 127.0.0.0/8 -j REJECT #Accept SSH connections -A INPUT -p tcp -m state --state NEW --dport 54321 -j ACCEPT #Accept Established connections -A INPUT -m state --state RELATED,ESTABLISH -j ACCEPT #Accept HTTP connections -A INPUT -p tcp -m tcp --dport 80 -j ACCEPT -A INPUT -p tcp -m tcp --dport 443 -j ACCEPT -A INPUT -p tcp -m tcp --dport 10081 -j ACCEPT #Accept all PING requests on ICMP -A INPUT -p icmp -m icmp --icmp-type 8 -j ACCEPT # Reject all other inbound - default deny unless explicitly allowed policy -A INPUT -j REJECT -A FORWARD -j REJECT COMMIT
Now we are going to load the file to check for errors and to ensure the configuration is valid and our firewall works as expected.
iptables-restore < /etc/iptables.test.rules
You can view the active firewall rules by running this command.
iptables -L
If everything is satisfactory, save the rules into a new file which we will then configure to be automatically loaded upon boot.
iptables-save > /etc/iptables.up.rules
Now we need to add a line to the network interface’s initialization script so that our firewall rules will be loaded upon boot.
nano /etc/network/interfaces
Add the following line after ‘iface lo inet loopback’:
pre-up iptables-restore < /etc/iptables.up.rules
Now before we do anything else, we need to test the configuration. We don’t want to inadvertently lock ourselves out of the server, so we will test the firewall by opening a new SSH connection in a new window. As long as we don’t close our currently active connection we can still make changes if our new SSH connection fails.
If you can successfully connect to the server with the new account on the new port with the firewall rules enabled, then you should reboot the server and verify that iptables loads your configuration file on boot.
sudo reboot
You will be disconnected from both your SSH sessions.
Try reconnecting after 20 or 30 seconds, log in and then check your firewall configuration.
iptables -L
If the rules load successfully then we can move onto the next step.
Time Synchronization Setup
Run the timezone package configuration wizard selecting your time zone.
sudo dpkg-reconfigure tzdata
Create a cron job script:
sudo nano /etc/cron.daily/ntpdate
Enter the following in the /etc/cron.daily/ntpdate file:
sudo ntpdate ntp.ubuntu.com
Change permissions of the cron job script:
sudo chmod 755 /etc/cron.daily/ntpdate
Configure User Locales:
sudo locale-gen en_US.UTF-8
Configure local time zone:
sudo ln -sf /usr/share/zoneinfo/America/Toronto /etc/localtime
Outgoing Mail Server Setup
Install postfix and mail tools:
sudo apt-get install postfix mailx
MySQL Installation
Run the following command to install MySQL:
sudo apt-get install mysql-server
Zend Server CE Setup
I prefer the manual installation method. Instructions can be found here on Zend’s site.
I use a portion of those instructions in my setup.
Define a new package repository by opening the following file: /etc/apt/sources.list and adding the line:
deb http://repos.zend.com/zend-server/deb server non-free
Now download the GPG key:
sudo wget http://repos.zend.com/deb/zend.key -O- |sudo apt-key add -
Update the package list:
sudo apt-get update
Install Zend Server with PHP 5.3. Note: Zend does provide Zend Server with PHP 5.2 packages. View the Zend Server CE documentation for more information.
sudo apt-get install zend-server-ce-php-5.3
I like to install phpmyadmin but it is optional:
sudo apt-get install phpmyadmin-zend-server