Building a QR Code Generator: A Simple SDK You Can Create Today

In a digital world swamped with complexity, there's something simple about QR codes. QR codes are used everywhere. A square grid of black modules on a white background, and yet it holds the potential to share complex data in a scan-friendly manner. What if I told you that you could build your own QR Code Generator SDK from scratch, and in under an hour? Not only will this equip you with a highly useful tool for your dev arsenal ⚒️, but it's also a simple and great project that provides a deeper understanding of how QR codes work.

In today's post, I will walk you through the entire process of building your own QR Code Generator SDK. Whether you're new to coding or a seasoned developer, this is a project that promises to be as educational as it is practical. So, if you're ready to go beyond being a user of QR codes to becoming a creator, read on!

Tools You'll Need

Before we start, make sure you have:

• A code editor like VS Code

• Python installed on your computer

Step 1: Create Your Project Folder

First, create a new folder for your project. Name it something clear and easy to remember. For this project, I named mine "QRCodeGeneratorSDK."

mkdir QRCodeGeneratorSDK
cd QRCodeGeneratorSDK

Virtual Environment

In your terminal, navigate to the project folder and run the following command to create a virtual environment:

python3 -m venv myenv

Activate the Virtual Environment

Now activate it. You can do this by running:

• Mac/Linux:

source myenv/bin/activate

• Windows:

myenv\Scripts\activate

Step 2: Install the Packages

You’ll need a specific package to help generate QR codes. Run the following command:

pip install qrcode[pil]

Or if you're using zsh and face an issue with brackets, try:

pip install qrcode\[pil\]

About the Package

The qrcode library makes it easy to create QR codes. The pil part is for the Pillow library, which helps us work with images.

Step 3: Write the Code

Create a new Python file in your project folder and name it qr_code_sdk.py.

Function Signature

First, let's define our function. Open qr_code_sdk.py and add:

def generate_qr(data, file_name):
    pass

Initialize the QR Code Object

Now let's add code to initialize a QR code object. Inside your generate_qr function, add:

    qr = qrcode.QRCode(
        version=1,
        error_correction=qrcode.constants.ERROR_CORRECT_L,
        box_size=10,
        border=4,
    )

Add Data to QR Code

Next, let's add data to the QR code object. Inside the function, add:

    qr.add_data(data)
    qr.make(fit=True)

Generate and Save the Image

Finally, let's generate the QR code image and save it. Inside the function, add:

    img = qr.make_image(fill='black', back_color='white')
    img.save(file_name)

Your final generate_qr function should look like this:

def generate_qr(data, file_name):
    qr = qrcode.QRCode(
        version=1,
        error_correction=qrcode.constants.ERROR_CORRECT_L,
        box_size=10,
        border=4,
    )
    qr.add_data(data)
    qr.make(fit=True)
    img = qr.make_image(fill='black', back_color='white')
    img.save(file_name)

Step 4: Test Your Code

Create a new Python file named test_sdk.py. Import your generate_qr function and test it:

from qr_code_sdk import generate_qr

generate_qr("Hello, World!", "hello_world.png")

Run test_sdk.py and check your project folder. You should see a new QR code image.

Wrapping Up

You did it! You built your own QR Code Generator SDK. Now you can customize it or add new features like custom colors or different sizes.

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That is it for this article, thanks for reading! ⚒️

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