Category: Programming

A big part of my work has to do with code. I’ve worked as system administrator – installing, patching, and configuring someone else’s code. I’ve worked as independent programmer, writing code on my own. I also programmed as part of the team. And on top of that, I worked as Team Leader and Project Manager, where I had to interact a lot with programmers. Programming world on its own is as huge as the universe. There is always something to learn. When I find something worthy or something that I understand enough to write about, I share it in this category.

termtosvg – record terminal sessions as SVG animations

termtosvg (GitHub repo) is a handy little tool that makes recording animated sessions in the terminal as simple as humanly possible. Instead of generating heavy graphics or video animations, this tool creates SVG files, which are a lot smaller and easier. There is also a selection of themes to choose from.

Th resulting SVG files can be used as quick demos and guides in READMEs on GitHub, or as tutorials for your application’s website.

How HTTPS Works in 10 Minutes

“How HTTPS Works in 10 Minutes” is a simple, high-level overview of how HTTPS works. It doesn’t dive into too much detail or heavy math. But it does cover the main stages of how the connection is established, verified, and encrypted. These are the stages that are covered:

  1. You go to an HTTPS website via your browser
  2. The Client says “Hello”
  3. The Server says “Hello”
  4. The Client makes sure the SSL certificate is legitimate
  5. The Client gets the public key from the SSL certificate
  6. The Client uses the public key to make more random bytes
  7. The Client and Server make session keys
  8. The Client and Server compare session keys
  9. If the session keys match, game on

Calculating distance using MySQL

“Calculating distance using MySQL” is a very useful blog post for everyone who works with geographical location data and MySQL. It shows a simple example of how to calculate the distance between two coordinates on a sphere (Earth in particular) within the MySQL itself.

SELECT ST_Distance_Sphere(
    point(-87.6770458, 41.9631174),
    point(-73.9898293, 40.7628267)
);

The above will return 1148978.6738241839, which is the distance between the two points in meters.

This functionality is available since MySQL 5.7. Have a look at the documentation of the spacial convenience functions.

MariaDB has similar functionality, but with a slightly different function names. Use ST_DISTANCE() instead of ST_Distance_Sphere(). Have a look at this blog post for more details.

GDPR cookie scanner

I came across the GDPR Expert service via this HackerNews thread. It is a service that helps website owners with the GDPR compliance. Behind the scenes, there is this open source tool, which scans for cookies and provides the details about the vendor and purpose of each identified cookie. The database includes more than 10,000 known cookies.

Very handy.