A URL Shortener API built with Go, Gin, MongoDB, and Redis. This API allows users to create, retrieve, update, delete, and track statistics of shortened URLs. Short URLs are essential in today’s digital landscape as they simplify sharing, improve readability, and save space in character-limited platforms like social media. They also enable better tracking and analytics, making it easier to monitor user engagement. For high availability and fault tolerance, I deployed the service on Google Cloud Run.

The project was implemented based on the roadmap requirements roadmap.sh.

• Create short URLs with a unique code
• Retrieve original URLs from short codes
• Update existing short URLs
• Delete short URLs
• Track access statistics
• Dockerized for easy deployment
• CI/CD with GitHub Actions

• Language: Go
• Framework: Gin
• Database: MongoDB
• Containerization: Docker
• Caching: Redis
• CI/CD: GitHub Actions
• Deployment: Google Cloud Run
• Artifact Registry: Google Artifact Registry

• Go (>=1.18)
• Docker & Docker Compose
• MongoDB

git clone https://github.com/mjthecoder65/url-shortener.git
cd url-shortener

Create a .env file in the root directory and populate it with the required variables:

touch .env

Example .env File:

APP_ENV=dev # prod, staging
MONGODB_URI=mongodb://localhost:27017/main
MONGODB_PASSWORD=your_mongodb_password
SERVER_ADDRESS=:8080
ALLOWED_CHARS=abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789
SHORT_CODE_LENGTH=6

Ensure MongoDB is running locally on port 27017 before starting the application.

docker-compose up -d --build --remove-orphans

make test

Request:

POST /api/v1/shorten
Content-Type: application/json

{
  "url": "https://www.example.com/some/long/url"
}

Response:

201 Created
{
  "id": "1",
  "url": "https://www.example.com/some/long/url",
  "shortCode": "abc123",
  "createdAt": "2021-09-01T12:00:00Z",
  "updatedAt": "2021-09-01T12:00:00Z"
}

Request:

GET /api/v1/shorten/abc123

Response:

200 OK
{
  "id": "1",
  "url": "https://www.example.com/some/long/url",
  "shortCode": "abc123",
  "createdAt": "2021-09-01T12:00:00Z",
  "updatedAt": "2021-09-01T12:00:00Z"
}

Request:

PUT /api/v1/shorten/abc123
Content-Type: application/json

{
  "url": "https://www.example.com/some/updated/url"
}

Response:

200 OK
{
  "id": "1",
  "url": "https://www.example.com/some/updated/url",
  "shortCode": "abc123",
  "createdAt": "2021-09-01T12:00:00Z",
  "updatedAt": "2021-09-01T12:30:00Z"
}

Request:

DELETE /api/v1/shorten/abc123

Response:

204 No Content

Request:

GET /api/v1/shorten/abc123/stats

Response:

200 OK
{
  "id": "1",
  "url": "https://www.example.com/some/long/url",
  "shortCode": "abc123",
  "createdAt": "2021-09-01T12:00:00Z",
  "updatedAt": "2021-09-01T12:00:00Z",
  "accessCount": 10
}

To ensure your CI/CD pipeline runs smoothly, you need to set up secrets and variables in GitHub Actions.

Go to your GitHub repository → Settings → Secrets and variables → Actions → Secrets → New repository secret

Add the following secrets:

• MONGODB_PASSWORD → Your MongoDB password
• MONGODB_URI → The connection string for MongoDB
• GCP_CREDENTIALS → JSON credentials for your Google Cloud service account

Go to Settings → Secrets and variables → Actions → Variables → New repository variable

Add the following variables:

• APP_ENV → production (or development)
• SERVER_ADDRESS → :8080
• ALLOWED_CHARS → abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789
• SHORT_CODE_LENGTH → 6
• ARTIFACT_REGISTRY_REGION → Your Google Cloud region (e.g., us-central1)
• GCP_PROJECT_ID → Your Google Cloud project ID
• ARTIFACT_REGISTRY_REPO → Name of your Google Artifact Registry repo
• CLOUD_RUN_SERVICE_ACCOUNT → Email of the service account with Cloud Run deployment permissions

This project uses Terraform to provision and manage the infrastructure required for deploying the URL Shortener API on Google Cloud Platform (GCP). The Terraform configuration automates the creation of networking resources, a Redis instance, an Artifact Registry repository, and a service account for CI/CD deployment via GitHub Actions.

The Terraform configuration provisions the following resources:

• Terraform: Install Terraform (>=1.0) on your local machine.
• Google Cloud SDK: Install and authenticate gcloud with your GCP account.
• GCP Project: A Google Cloud project with billing enabled.
• Service Account: A GCP service account with permissions to manage resources (e.g., Owner or specific IAM roles).

# Set the following environment variables in your terminal. Replace the placeholders
# with your own values
export REGION=asia-northeast3
export ARTIFACT_REPOSITORY_NAME=url-shortener
export GOOGLE_PROJECT_ID=rock-elevator-453623-f5
export IMAGE_TAG=v1
export IMAGE_NAME="${REGION}-docker.pkg.dev/${GOOGLE_PROJECT_ID}/${ARTIFACT_REPOSITORY_NAME}/url-shortener:$IMAGE_TAG"

# Create Artifact repository
gcloud artifacts repositories create "$ARTIFACT_REPOSITORY_NAME" \
  --repository-format=docker \
  --location=$REGION

# Authenticate Docker to push images to Artifact Registry
gcloud auth configure-docker

# Build the Docker Image
docker build -t "$IMAGE_NAME" .

# Push Docker Image to Artifact Registry
docker push "$IMAGE_NAME"

gcloud run deploy url-shortener \
  --image="$IMAGE_NAME" \
  --platform=managed \
  --region="$REGION" \
  --allow-unauthenticated

This project is licensed under the MIT License.

Michael Jordan