Articles

Curl is an incredibly useful tool and has all sorts of flags and options available for every situation. I tend to use curl quite a lot for all kinds of stuff, and not just downloading large files. So I thought I would post a few of the most common things that I use the tool for. Note that most of the following URLs don't really exist, they are just for demo purposes. I have also left out the output of these commands as they vary from a few lines to many pages of output.

Basic HTTP authentication is a simple authentication mechanism that is used to prevent access to a site or directory on a server. It is by no means the most secure authentication mechanism but it is commonly used on staging sites in order to prevent unwanted access. This is a good way of preventing search engine bots from spidering the staging site, which is undesirable as it can cause staging site pages appearing in search engines results.

The usual route to set this up is to create a .htaccess that sets up the authentication and references a .htpasswd file to create the username and password details. This can mean editing the .htaccess file in order to setup the password correctly. Unfortunately, this creates a .htaccess file that shouldn't be added to the repository as it would mean that the live site would also be password protected when the code is deployed.

At the LAMP and Beyond III event (run by PHPNW) this weekend we set ourselves the task of giving PHP7 a go. Below is some nodes from that session.

This assumes that you’ve already installed PHP5.6 along with Apache and MySQL. Installing PHP5.6 via apt-get is fine as we just need some of the dependencies to be present.

To get the the code for PHP7 you need to clone from the PHP repo on Github.

git clone git@github.com:php/php-src.git php-src

Go into the php-src directory and run the ./buildconf command, this will generate a configuration file.

./buildconf

Before you run config you’ll need to install some dependencies (there are one or two).

When generating markup in Drupal you'll often want to store the output in a cache instead of regenerating it every time. This is especially important for potentially expensive rendering tasks that don't change between page requests. Drupal 7 comes with a cache system that can be taken advantage of with the cache_get() and cache_set() functions. There is also a third function called drupal_static() that also fills in gaps between these two functions.

Nearly a month has passed since my visit to London for this year's DrupalCamp and I thought I would put my thoughts down on the blog. I went down with a group of colleagues from my company Access on the Friday night before the event, having arranged a flat through Airbnb for all of us to stay in. After some beers and a burger we were ready for the main event on Saturday morning.

Varnish is a web application accelerator that helps to speed up websites. It works by sitting in front of the web server and caching web pages that are served by it.

When a request for a web page is made Varnish passes this request on to the web server, which then responds to the request as it normally would. Varnish then caches the result of this request before sending it to the user.

JSON is a very common data format, but reading it can be a little difficult, especially if the JSON contains very little white space. If you have Python 2.6 or above you have use the json.tool to format the JSON so that you can read it correctly. This is also a good way to validate JSON strings that you have had to hand edit before they cause errors upstream.

If you have a file called file.json, which contains a bunch of JSON output, you can use Python to format this into a readable structure in the following way.

python -m json.tool file.json

You can also write this output directly into a file, in this case called formatted.json.

python -m json.tool file.json > formatted.json

The most common use of this tool is to pipe JSON to it from the command line (either directly or via a script).

The annual PHPNW conference, now in it’s 7th year, was held on the 4th and 5th of October in Manchester, again in the Manchester Conference Centre. The conference was attended by over 400 people with over 30 speakers from all over the world who talked about everything from project management to the internals of PHP. I have been volunteering at PHPNW for a few years now, but this year I was able to attend as a delegate with a number of colleagues from Access. It’s been a few weeks since the event, but I haven’t had a chance to publish this review, so here it is.

When doing an audit of an existing Linux server a good first step is to find out what distribution is running and if the server is running a 32 or 64 bit architecture.

To find out what architecture a server is running you can run the uname command, which will print out certain system information. This must be supplied with the -a flag in order to print out as much information as possible.

uname -a

This will print out a line similar to the following on an Ubuntu system.

Linux vlad 3.2.0-23-generic #36-Ubuntu SMP Tue Apr 10 20:39:51 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux

This can be broken down bit by bit and will contain the following information.

Varnish is a web application accelerator that provides an easy speed increase to most web applications and Drupal is no exception. It works by creating a reverse proxy service that sits in front of your web server and caches traffic that comes through it. When the page is requested, Varnish forwards the request to the web server to complete the request, the response that comes back from the web server is then cached by Varnish. This means that the next request to the same page is served by Varnish and not the web server, which results in a large speed increase.

The upshot of using Varnish with an application like Drupal is that when a request is made there is no hit to the web server (and thus PHP) and no hit to the database. Varnish works best with Drupal with anonymous traffic, as authenticated traffic requires cookies and custom HTML. Even so, you can see massive speed increases for any anonymous traffic on the site.