Juan Valencia's website

I originally wrote this piece a few years back, but I believe that the principles still apply nowadays.

During my career I worked in different companies that are dedicated to the design and development of websites. On several occasions I was requested to add different features to commercial websites that even though I knew that they would be counterproductive, I had to add them anyway, as that was my job. Once I started freelancing, the truth is that things didn't change, only now the requests were being made directly to me by my clients, and even though I pointed out some of my concerns to clients with whom I had a good relationship, more often than not I had to do it anyway, after all it is the clients decision.

However, if you are reading this article, it's because you already have an interest to learn about common errors made in commercial websites. If you intend to turn your website into a good marketing tool, then here are some things that you should be aware of while having your website design.

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Categories: Thoughts

In the previous post, we created scaled thumbnails of images that maintained their aspect ratio. In this post we will see how to crop and scale the image to fill the thumbnail area.

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Categories: PHP, Programming

It's always a good idea to generate as many different sizes of thumbnails as are required in a web based system, right after an image is uploaded. Some of the advantages of generating and storing the thumbnails are that you can reduce the processing time that your server needs to use if you generate the thumbnails on demand, and of course you can reduce the consumed bandwidth by not sending the full size image when this is not necessary.

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Categories: PHP, Programming

As I have previously posted in this website, I believe it is a good idea to standardize in one character encoding across all parts of a system, and as my preferred character encoding is UTF-8, when I create a PHP system I check the following things:

• That the browser receives and interprets the output of my PHP scripts as UTF-8.
• That the (X)HTML forms accept UTF-8.
• That PHP treats the data received from a MySQL database as UTF-8.

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Categories: (X)HTML, Apache, FOSS, MySQL, PHP

Sometimes that we need to connect via SSH into another computer, we find out that this computer that we intend to SSH into (which we are going to call "destiny") may be utilizing NAT and therefore it doesn't count with a public IP address that we could use to connect to it, or it may be behind a firewall that won't allow access from the outside.

If "destiny" can successfully establish a SSH connection to another computer that is accessible, we can utilize this second computer to establish a reverse SSH tunnel to our "destiny" computer, we are going to call this second computer "origin" (even if it is not actually the computer that we are going to use to manage "target" remotely, but only a bridge).

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Categories: Commands, FOSS, Linux, SSH

Since I didn't find any lecture that I liked for KTouch, at least not one that allowed me to simply practice typing with a large number of random words, I thought it would be useful to create one based in random words taken from one of the lists of words usually located in /usr/share/dict, although this very same procedure can be use with any list of words. It didn't take to long to do it, but nevertheless it was interesting.

I include at the end the lecture that results from this procedure, as well as a lecture based in the words from the book The Adventures of Sherlock Holmes.

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Categories: Commands, FOSS, KDE, Linux, Text manipulation