python-urlshortener-cdk

A Python Based URL Shorter deployed to AWS via CDK.

Based on the url-shortner example from the aws-cdk-samples repo.

Shortening Logic

There are 3 different URL shorteners defined in lambda/shortner.py which increase in complexity. All of these shorteners implement the Abstract Class AbstractShortner which defines the base interface for a URL Shortner with functions to shorten a long URL into a slug and expand a slug into a long URL.

The first shortener uses a UUID generator to generate a random string of letters and numbers, which is a fine solution. However, the second shortener builds on this and uses an alphabet of non-ambiguous, lowercase characters to improve readability and increase input speed for users. The third shortener uses a custom Amazon DynamoDB Dictionary to add stateful storage, which will be necessary when we deploy this code to Lambda where we cannot rely on the memory of the function to be persisted.

AWS Deployment

Setup

Create and source a Python virtualenv on MacOS and Linux, and install python dependencies:

python3 -m venv venv
source venv/bin/activate
pip install -r requirements.txt

Install the latest version of the AWS CDK CLI:

npm i -g aws-cdk

Configuration

Configure the account id, Region, Hosted Zone Name, and Hosted Zone ID at the top of app.py to the values correct for your account.

Deployment

If this is the first time you are running CDK in this account, you will need to bootstrap your account, which can be done via:

cdk bootstrap aws://ACCOUNT-ID/REGION

At this point, you should be able to deploy the stack in this app using:

cdk deploy

If you want to clean everything up after you are done:

cdk destroy