How to type a degree symbol in Linux

Today, I came across a document where I had to type a degree symbol in Linux. Thanks to this post at Arch Linux Forums, it was painless to find out how. So here it is:

In windows, apparently you hold down Alt+0176.

Linux is different and to achieve the same, hold down Ctrl+Shift and type u+00b0, though if you are writing for html, the correct symbol is

°

Alternatively you can copy and paste it from this table on wikipedia, which includes other useful symbols like Pound, Registered and Copyright.

It will actually type the u00b0 until you complete and then it will form the degree symbol like so: °

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Pluf – A PHP5 Port of Django

Pluf is a PHP Framework developed as a port of Django to PHP. It claims to be simple, elegant and easy for people used to Django but in PHP5 so easy to deploy all over the world.

After reading the documentation, the file layout and concepts are all quite similar to django, though a downside is that we lose much of the beauty of the Python language and it doesn’t seem to have the Admin interface that makes django so delightful to work with.

Here is a sample of a helloworld, which would exist in a file called “Hello/Views.php”


< ?php
class Hello_Views
{
    public function hello($request, $match)
    {
        return new Pluf_HTTP_Response('Hello World!');
    }
}

as you can see, it is reasonably similar to (though more verbose than) Django’s equivalent “/hello/views.py” which would look like this:


from django.http import HttpResponse
def index(request): 
    return HttpResponse("Hello world")

Check out the full helloworld tutorial of Pluf

ORM

Pluf has an ORM that applies similar concepts and ideas as Django’s ORM, though as with the helloworld, it is slightly more verbose. The rest of the framework follows the same patterns, urls.php has a more verbose PHP regex patterns than django’s urls.py

Caching

Pluf runs it’s own caching system as well as being able to utilise APC and Memcached

Django vs Pluf

So what exactly does Pluf offer in ways of advantages over Django and why would you choose to use it instead? The obvious reasons are if you are well setup as a PHP developer. You work with tools and ide’s setup specifically for PHP, you have hosting infrastructure setup for PHP and you work with developers who are well versed in PHP. The other advantage of Pluf is that it comes with a migration framework out of the box, whereas django doesn’t and you need to use one of the available database schema migration, the most promising currently looks like South

Of course, Django deployment is becoming much simpler recently by leveraging the tutorials and tools like virtualenv, pip and most recently modrails has begun supporting python wsgi services. I recently performed some benchmarks with modrails vs fastcgi against a django blogging application called byteflow and modrails provided approx 1.8x speedup. More to come on that later.

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How to compress css & javascript: An alternative to mod_deflate or mod_gzip

So, you have used Website Optimization Analyzer or you installed Yslow for Firefox or you discovered somewhere else that compressing your files (html, javascript & css) is a good thing to do. Unfortunately, it’s not always as easy as it looks to do this.

In Apache web hosting environments, there is a module called mod_deflate (for 2.x versions) or mod_gzip (for 1.3) versions. This is generally the easiest way to get content compressed. As in my last post about Magento, you should normally be able to enable this safely with the following lines inside your .htaccess file in your www root of your website:



# Insert filter
SetOutputFilter DEFLATE
# Netscape 4.x has some problems...
BrowserMatch ^Mozilla/4 gzip-only-text/html
# Netscape 4.06-4.08 have some more problems
BrowserMatch ^Mozilla/4\.0[678] no-gzip
# MSIE masquerades as Netscape, but it is fine
BrowserMatch \bMSIE !no-gzip !gzip-only-text/html
# Don't compress images
SetEnvIfNoCase Request_URI \.(?:gif|jpe?g|png)$ no-gzip dont-vary
# Make sure proxies don't deliver the wrong content
Header append Vary User-Agent env=!dont-vary

Then visit your website and in your browser right-click on the web page and choose “View Source”. In the source code, try and find a line that contains your stylesheet, then we go to whatsmyip compression checker and we enter the whole URL to your stylesheet there. To test, enter my css url.

http://www.opensourcetutor.com/wp-content/themes/hemingwayEx/style.css

You should see a big green tick and the site will say the CSS is compressed. Now, if you don’t, you either haven’t applied my above .htaccess settings yet or mod_deflate is not enabled on your server for you to access.

Alternative #1 – requires Apache mod_rewrite

This method is probably the best method I have seen to overcome the mod_deflate issue and we are only concerned about javascript and css files for now. PHP has an easy method to compress php files on the fly. What we need to do is gzip all our javascript & css files.

If you have shell access, you can run this command to take of the job for you. It will find each and every javascript file and css file and create a gzip copy.

find . -regex ".*\(css\|js\)$" -exec bash -c 'echo Compressing "{}" && gzip -c --best "{}" > "{}.gz"' \;

The line above searches the current directory and any subdirectories for files with extensions .js or .css, then prints out that it is being compressed, then compresses with the highest compression in that directory leaving the original file as is.

Now, we need to tell our browser to access the gzip version *IF* it supports gzip encoding. To do this, we use the following in our .htaccess file. Make sure you have removed the above code if it wasn’t successful.



  AddType "text/javascript" .gz
  AddEncoding gzip .gz


  AddType "text/css" .gz
  AddEncoding gzip .gz

RewriteEngine on
#Check to see if browser can accept gzip files.
ReWriteCond %{HTTP:accept-encoding} gzip
RewriteCond %{HTTP_USER_AGENT} !Safari
#make sure there's no trailing .gz on the url
ReWriteCond %{REQUEST_FILENAME} !^.+\.gz$
#check to see if a .gz version of the file exists.
RewriteCond %{REQUEST_FILENAME}.gz -f
#All conditions met so add .gz to URL filename (invisibly)
RewriteRule ^(.+) $1.gz [QSA,L] 

The advantage of this Alternative is that our server doesn’t have to gzip / compress the javascript and css each time it is called. This eases the load up on the server as we already do the compression one time and then just call the compressed version from then after. The other advantage is that we don’t need to load up mod_deflate each time. This could be advantages if you are running a VPS with very low memory available.

If you have a static website, you could apply the same technique for all your html files. To do so, you would instead use this line:

find . -regex ".*\(html\|css\|js\)$" -exec bash -c 'echo Compressing "{}" && gzip -c --best "{}" > "{}.gz"' \;

and then add this into your .htaccess also



  AddType "text/html" .gz
  AddEncoding gzip .gz


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suhosin causing grief on Joomsuite component


Hopefully this helps me or someone else with the same issue in the future

suhosin[25917]: ALERT – configured POST variable limit exceeded – dropped variable ‘task_com_morfeoshow[]’ (attacker ‘xxx.xxx.xx.xxx’, file ‘/home/user/public_html/administrator/index.php’)

in your php.ini (or suhosin.ini depending on your setup)

[suhosin]
suhosin.post.max_vars = 2000
suhosin.request.max_vars = 1000

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How to Speed up Magento

Having implemented a number of websites now in Magento and being the web hosting provider for them also, it’s been both challenging and rewarding trying to get Magento running at an acceptable speed.People generally don’t understand what’s happening when they say “my website is slow”. So, for those of you unfamiliar with benchmarking / understanding what factors to consider when a page loads from a server, we have quite a number of variables.

  1. Your URL you type into a browser, translates to an IP address – this check should take a very, very short time
  2. Your browser then begins to access the web server where your website is hosted to ask for the page you want, this can cause some delay, typically 40-200ms (bottleneck 1.)
  3. In the case of Magento,it uses PHP as the software language that runs the site, so the php begins to execute (bottleneck 2.)
  4. PHP then reaches a part of it’s code it needs to access the database to retrieve website data and sometimes insert information about who you are. (bottleneck 3.)
  5. The PHP code retrieves the information, does a bit more computing on it (for simplicity, this is still bottleneck 2) and then sends it to your web server
  6. Your webserver can then send it or compress it and then send it to you (bottlneck 4)
  7. The data is sent over the internet to your browser (bottlneck 5)
  8. Your browser must ‘render’ the data it receives into an actual web page (bottleneck 6)

I will assume you are here specifically for Magento issues, so let’s get started with the basics. I will make the assumption that your web server is running Apache and you have very little control over that.

Preparation – the “before”

  1. If you are familiar with the, use Firefox and the Firebug extension and the Yslow extension. Take a screenshot of your statistics.
  2. Alternatively, what I suggest is to go to WebsiteOptimization if you’re fairly new to this. You basically enter your URL and click. Print out the page, preferably to PDF before we begin.

Check Magento Caching is turned on (if not developing still)

  1. Login to your Magento Admin
  2. go to System -> Cache Management
  3. in the dropdown box, choose “enable” and tick all the boxes, then save settings.

Let’s start simple – .htaccess and gzip/deflate

  1. Go to mod_gzip tester and enter your magento site address. If it comes back with a big green tick and says http://yourmagentosite.com is gzipped, then you’re in business and skip step 2. If not..go to step 2
  2. Using ftp or ssh, however you access your magento website, go to the root of the site and find your .htaccess file. Scroll down until you see something like:


  3. # Insert filter
    SetOutputFilter DEFLATE
    # Netscape 4.x has some problems...
    #BrowserMatch ^Mozilla/4 gzip-only-text/html
    # Netscape 4.06-4.08 have some more problems
    BrowserMatch ^Mozilla/4\.0[678] no-gzip
    # MSIE masquerades as Netscape, but it is fine
    BrowserMatch \bMSIE !no-gzip !gzip-only-text/html
    # Don't compress images
    SetEnvIfNoCase Request_URI \.(?:gif|jpe?g|png)$ no-gzip dont-vary
    # Make sure proxies don't deliver the wrong content
    Header append Vary User-Agent env=!dont-vary

  4. Make sure it looks like above. A hash in front of the line means it’s commented out. If your .htaccess file does look like this AND mod_gzip tester is still not showing enabled, you need to talk to your web hosting provider. They may not allow overrides or may not have the deflate module installed or enabled. If it doesn’t look like the above, remove the hashes from your lines so that it reflects what is above, then retest with mod_gzip tester
  5. Take a screenshot / pdf printout of Yslow / websiteoptimizer results. ;)

Let’s shrink our javascript

  1. Magento uses A LOT of LARGE javascript libraries and depending on your template, it’s a good chance that these make up for 50% of your website page size. This should only affect the first page load but it’s often the first impressions that count, so let’s shrink it.
  2. For this, we will use the Fooman Speedster Extension from magentoconnect. Click on the “get extension key” and then copy the key to your clipboard.
  3. Now go to your magento store admin interface and click on “System -> Magento Connect -> Magento Connect Manager”. Enter your admin user/pass to access magento connect manager.
  4. *Warning – once you install the extension until you fix your .htaccess, it may break your website*
  5. Paste the extension key to install the extension
  6. Now go to your .htaccess and under the line: #RewriteBase /magento/ add this line

    RewriteRule ^(index.php/)?minify/([^/]+)(/.*.(js|css))$ lib/minify/m.php?f=$3&d=$2

  7. Save your .htaccess and access your site (it may take a while to load the first time as it minifies and creates it’s cache.
  8. **Test your site is working properly**
  9. Take a screenshot / pdf printout of Yslow / websiteoptimizer results. ;)

Let’s check our php settings

  1. Create a file called phpinfo.php and enter this information into it.
  2. Check for the following: memory_limit
  3. If it’s less than 128M, try and add an entry into your .htaccess like so:
  4. php_value memory_limit 128M

Finally, MySQL – for experienced users.

  1. If you’re a mysql hero, you don’t need me to tell you how but we want to try and get the following settings in your my.cnf
  2. query_cache_type = 1
    query_cache_size = 32M
    query_cache_limit=2M

  3. If you don’t have root access to check /etc/my.cnf (or /etc/mysql/my.cnf) variables, then login to mysql or use phpmyadmin to show variables.

  4. $ mysql -u mysqluser -p magento_database_name
    $ mysql> SHOW VARIABLES;

  5. If you don’t have control over your mysql configuration, go knocking on your Web Host’s support tickets to get them to modify it to suit you or if you’re in Australia, check us out

**If you want someone to do this all for you, lodge a support ticket at Yourwebhostingsupport with the Subject “Magento Optimisation”

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Getting and Managing Free Fonts for Linux – aimed at Ubuntu

One area sadly lacking in most Linux installs is the availability of really nice fonts useful for design and great fonts are not cheap, circa $150 for a font set. Best all in one location for getting great free fonts, I think is www.fawnt.com

If Ubuntu really wants to have a go at competing with the Mac, this is certainly an area that needs improving.

You can install fonts system wide by dropping them (or folders of font families) into /usr/share/fonts or alternatively, kfontviewer a KDE application will give you a nice gui for installing fonts.

Need to manage large amounts of fonts on Linux? Try Fontmatrix

sudo apt-get install fontmatrix

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DimDim – Open source Web conferencing and Meetings


For my future reference. DimDim is an open source web conferencing and meeting software with the following features:

  • No Install to Host/Join meetings
  • Easy Share Screens&Webpages
  • Audio & Video Conferencing
  • Present PowerPoint and PDFs
  • Private & Public Chat
  • Whiteboard & Annotations
  • Record and Playback Meetings
  • Open Source and open APIs
  • SynchroLive Co-Browsing
  • Free Recording & Archiving
  • Mac & PC Screen Sharing (no Linux??)
  • Multiple Presenters
  • Free Teleconferencing Calls
  • Secure, Private Meetings
  • Faster and Easier than ever
  • No Install to Host meetings

It’s available as a vmware virtual appliance or for those of you using Qemu / KVM / Xen, you should be able to convert the image using:

qemu-img convert -f vmdk -O qcow

Solar, Steam & Open Source Farming Technology

While searching around for parabolic trough’s yesterday, I stumbled upon this site.

We are building the world’s first replicable, open source, modern off-grid global village – to transcend survival and evolve to freedom. We are farmer scientists – working to develop a world class research center for decentralization technologies using open source permaculture and technology to work together for providing basic needs and self replicating the entire operation at the cost of scrap metal. This is a stepping stone to transcending survival and evolving to freedom. Factor e Farm is the land-based facility where we put this theory, Open Source Ecology, into practice. Visit the site

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Quick Lightbox effect for any content in Joomla 1.5


Joomla 1.5’s use of Squeezebox in the backend makes for easy use in the frontend. Thanks to this article at Dvector.com I was able to mash up a lightbox style feedback form for category listing in sobi directory component.

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