How To Set Up AWS CDK With Python

Table of Contents

What’s up, guys!

In this article, you’ll be learning how to set up AWS CDK with Python. AWS CDK is a tool by Amazon AWS which is used to create resources in the AWS cloud programmatically. This toolkit is an alternative to existing tools like Terraform, CloudFormation, etc. This is especially for programmers who want to put conditional stuff that requires programming logic in order to deploy or create certain resources.

How To Set Up AWS CDK With Python

Setup PIP and Virtualenv

First, Install the required Python dependencies:

$ python -m ensurepip --upgrade

$ python -m pip install --upgrade pip

$ python -m pip install --upgrade virtualenv

Setup NPM

If you have this set up already in your system skip to the next section.

First, we will install NPM as we will be using this to install AWS CDK tool.

# Ubuntu/Debina

$ apt install nodejs


# Mac

$ brew install nodejs


# Redhat based or later version

$ yum install nodejs

Verify NPM

$ npm --version

Output:

$ npm --version
8.5.5

Also, you might want to learn : How to setup Node.js on ubuntu through NVM.

Install AWS-CDK

Now, install AWS CDK using npm:

$ npm install -g aws-cdk

Verify AWS-CDK

Run the version command:

$ cdk --version

Output:

$ cdk --version
2.9.0 (build a69725c)

Example: Create First CDK Project

After the successful installation of CDK, we’re ready to create our first test project to start doing things with it.

$ mkdir example_app
$ cd example_app
$ cdk init app example_app --language python

Output:

Applying project template app for python

# Welcome to your CDK Python project!

...

Enjoy!

Please run 'python3 -m venv .venv'!
Executing Creating virtualenv...
✅ All done!

Inside the project directory, it initializes a virtualenv. (if you haven’t installed virtualenv, install it first)

Or, you can also initialize your own virtualenv. (by running python -m venv .venv inside the project directory.)

Check the .venv file:

$ ls -al | grep venv

Output:

ls -al | grep venv
drwxr-xr-x  5 zugger zugger 4096 Apr 25 15:36 .venv

Since it is initialized already, the first thing we need to do is activate the virtual environment. To do so run the following command:

$ source .venv/bin/activate

Now that we are inside the python virtual environment and we can install some dependencies.

Add any dependencies or requirements your project may need in the requirements.txt file and install it by running:

$ pip install -r requirements.txt

You can add needed dependencies later on also and run the same command to install.

Verify Python AWS CDK

To verify let’s enter into the python shell:

$ python

And run followings:

>>> import aws_cdk
>>> from aws_cdk import aws_ec2 as ec2
>>> ec2

The output will be:

As shown above, if everything works fine then you have successfully installed and set up AWS CDK for Python.

Initialize AWS CDK Stack

Before starting deploying stack:

Region: The default region your stack will be deployed on.
Account: Your AWS account.

Here, CDK tool has pre-created a Python file called app.py which contains these details in the init function to keep things clean.

import os

import aws_cdk as cdk

from example_app.example_app_stack import ExampleAppStack

app = cdk.App()
ExampleAppStack(app, "ExampleAppStack",
    # If you don't specify 'env', this stack will be environment-agnostic.
    # Account/Region-dependent features and context lookups will not work,
    # but a single synthesized template can be deployed anywhere.

    # Uncomment the next line to specialize this stack for the AWS Account
    # and Region that are implied by the current CLI configuration.

    #env=cdk.Environment(account=os.getenv('CDK_DEFAULT_ACCOUNT'), region=os.getenv('CDK_DEFAULT_REGION')),

    # Uncomment the next line if you know exactly what Account and Region you
    # want to deploy the stack to. */

    #env=cdk.Environment(account='123456789012', region='us-east-1'),

    # For more information, see https://docs.aws.amazon.com/cdk/latest/guide/environments.html
    )

app.synth()

If you see the lines above the account and the region is passed on your Environment function, feel in the attributes with the information you have.

Synthesize and Deploy AWS CDK Stack

A stack is basically a set of AWS resources that you can use and manipulate programmatically using your CDK.

In order to do this you simply need to run:

$ cdk synth ExampleAppStack

To deploy the changes:

$ cdk deploy ExampleAppStack

These commands will basically let you synthesize and then deploy a stack named ExampleAppStack.

That’s it!

Conclusion

In this, you have learned about how to set up AWS CDK with python with an example.

Thank you!

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