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Computing

What to do when gitignore doesn't work

How to fix .gitignore not working on your repository

If you’re using a Git-based source control, you might be familiar with the use of a .gitignore file to list files which Git is supposed to ignore when tracking files and making commits. This can be particularly useful when using Git (if you’re using GitHub Desktop, you’re also using Git) as a source control tool for projects that generate temporary or user-specific files at every run, such as Unity, as these files cannot be shared across different users of the project.

User-generated files in Unity
User-generated files in Unity that don’t need to be tracked by Git.

Sometimes, when setting up the repository, because of a .gitignore that is not properly set up, files that you intend to be ignored can actually get committed into the repository. If that happens, retroactively applying the .gitignore list will not help.

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A primer on Base 64 strings — Part 1

A primer on Base 64 strings — Part 1: Introduction

If you have been around the web for awhile, you will notice that sometimes, you will find a series of gibberish alphabets appearing, most often in your browser address bar as part of a website’s URL:

The blue highlighted portions in the GIF above are the aforementioned gibberish alphabets.

These are Base 64 characters, and a large portion of the web uses these characters for a multitude of purposes.

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Setting up a virtual Postfix mail server — Part 3

Setting up a virtual Postfix mail server — Part 3: Implementing DKIM, DMARC and rDNS

In the previous part of this tutorial series, we set up a mail server that could accept connections from mail clients like Gmail. This allowed us to send out domain emails using a mail client, instead of having to implement a mailbox on our server.

With our mail server’s basic functionality properly set up, we can now turn our attention to another problem — email deliverability. Spam email is a really big problem online, so many email providers have some kind of system in place to assess whether an incoming email is spam and either flag it, or reject it. Hence, after setting up our mail server, one thing we need to do is to ensure that our mail server conforms to certain email security standards, policies and protocols. This goes a long way to help us communicate to other mail servers that we are trustworthy, so that our emails will be deliverable.

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Setting up a virtual Postfix mail server — Part 2

Setting up a virtual Postfix mail server — Part 2: Sending emails with SASL

In the first part of this series, we set up a basic virtual mail server with Postfix that received emails for our domain and forwarded it to a mailbox of our choice. To round off the basic set of features for our mail server, we will be setting up Simple Authentication and Security Layer (SASL) to work with Postfix, so that we can access our mail server with a mailbox client (like Gmail) and send out emails from our domain.

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Setting up a virtual Postfix mail server — Part 1

Setting up a virtual Postfix mail server — Part 1: Receiving emails with mail forwarding

If you own a domain, and are looking to set up email hosting for it, you have a couple of options. You can either:

  1. Get a generic web hosting service that comes with a cPanel-based email hosting service, or;
  2. Use services like Google Workspace or Microsoft’s Enterprise Email Service.

The former option is cheap, but can be clunky to use and ineffective with blocking spam. The latter option — being specialised services — are generally much more accessible and effective with spam, but cost more.

There’s actually also a third option, and that is:

  1. Running your own mail server on a cloud server.

This means that you have to set up the server and maintain it, but it also means that you can have a cheap and effective mail server, instead of having to choose between one or the other.

In this series of articles, we are going to explore how we can set up a virtual mail server using a Mail Transfer Agent (MTA) called Postfix. This will be a fully-featured mail server, meaning that over the course of these articles, we will be building a mail server that can:

  1. Send and receive emails,
  2. Filter incoming emails for spam, and;
  3. Pass email policy checks, so that the emails it sends out are not flagged as spam.
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Importing CSV files into a MySQL table

Importing a CSV file into an SQL table

CSV stands for Comma-Separated Values, and CSV files are text files that look something like this:

example.csv

Username,Email,Address,Contact
johndoe,john@example.com,"71 Pickering Street, Singapore, Singapore",+65-91234567
janedoe,jane@website.com,"24 Raffles Lane, Singapore, Singapore",+65-81234567
marysmith,mary@smith.com,"83 Riveting Road, Singapore, Singapore",+65-97654321
bobsmith,bob@smith.com,"84 Riveting Road, Singapore, Singapore",+65-87654321

Essentially, the CSV file format is meant to represent tabular data. The above CSV file represents the following table:

UsernameEmailAddressContact
johndoejohn@example.com71 Pickering Street, Singapore, Singapore+65-91234567
janedoejane@website.com24 Raffles Lane, Singapore, Singapore+65-81234567
marysmith mary@smith.com 83 Riveting Road, Singapore, Singapore +65-97654321
bobsmith bob@smith.com 84 Riveting Road, Singapore, Singapore +65-87654321

Due to their tabular nature, data in a CSV file can very easily be imported into and stored in an SQL table. The commands to do that, however, are not very well-documented online.

If a CSV file does not open as a text file on your computer, that’s because your computer is opening the file with a spreadsheet program such as Microsoft Excel. In such a case, to see the file as text, you will want to open these files on a text editing software such as Notepad.

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Creating a farming RPG in Unity - Part 3: Farmland Interaction

Creating a Farming RPG (like Harvest Moon) in Unity — Part 3: Farmland Interaction

Correction: In the video, we made a reference to the PlayerController component in the PlayerInteraction class. However, we later found that we didn’t make use of it at least in this part, so you can choose to skip that bit in the video for now, as it is redundant. They are highlighted in red in the finalised codes below.

Ever wanted to create a game like Harvest Moon in Unity? This is Part 3 of our guide, where we go through how to set up farmland elements that our player character will interact with. You can also find Part 2 of our guide here, where we went through how to set up our player camera.

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Pretty Computer Chips
Image by Jonas Svidras at https://stocksnap.io/photo/intel-8008-LBYK1XTHFC.

Passing a variable by value vs. reference

In programming, a concept that usually creates a lot of confusion among those new to it is the concept of passing a variable by value, versus passing a variable by reference. The 2 examples below illustrate the difference between these two ways variables can be passed in Java:

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