Crypto Price Aggregator Service Development

Tonko Knez

Completed work

Software Engineer

Docker

Terraform

Cryptocurrency & Blockchain

Crypto Price Aggregator Service

A minimal microservice written in C language that fetches live Bitcoin price from Kraken API and serves it over HTTP API. It also provides a Prometheus /metrics endpoint for monitoring.

Features

Simple HTTP API (/) → returns BTC price.

Dockerized microservice

Unit tests

Static analysis via cppcheck

CI/CD with GitHub Actions

Terraform (AWS deploy)

Prometheus metrics endpoint:

requests_total → count of HTTP requests.

btc_price_usd → current BTC price (updated on request).

Build & Run

Local Development

To build and run locally, you need the following dependencies installed on your host:

libprom

libpromhttpd

libmicrohttpd-dev

libcjson-dev

libcurl4-openssl-dev

build-essential

Then you can build and run:

make run
./crypto_service
# Service runs at http://localhost:8080 and http://localhost:8080/metrics

Run static analysis

make static-check

Run unit tests

make test

Buid & run in container (Docker/Podman)

podman build -t crypto-service .
podman run -p 8080:8080 crypto-service

# Static check
podman build -f Dockerfile.test -t crypto-service:test .
podman run --rm crypto-service:test make static-check

# Unit tests
podman build -f Dockerfile.test -t crypto-service:test .
podman run --rm crypto-service-sqr:test make test

Deployment

Prerequisites

AWS credentials with permissions for ECS, ECR, IAM, and VPC.

Terraform CLI installed.

Deploying manually

Set environment variables on your Linux terminal or via GitHub secrets (CI/CD):

export AWS_ACCESS_KEY_ID="your_access_key"
export AWS_SECRET_ACCESS_KEY="your_secret_key"
export AWS_REGION="us-east-1"

Initialize Terraform:

cd terraform
terraform init

Apply Terraform configuration:

terraform apply -auto-approve

Once deployed, find the service IP in AWS ECS Console and test::

curl http://<TASK_PUBLIC_IP>:8080

Cleanup:

cd terraform
terraform destroy -auto-approve

CI/CD

CI/CD microservice build, test and deployment to AWS ECS is automated via GitHub Actions with pipeline definition stored in ci-cd.yml file.

Note

Requires an IAM User created in AWS for CI/CD with restricted permissions and AWS Credentials added to GitHub.

🔍 Monitoring & Metrics

This project includes a /metrics endpoint (Prometheus format) exposed by the crypto service.

Run Monitoring Stack

# Build service (Podman or Docker)
podman-compose build --no-cache crypto-service
podman-compose up -d

# Test API
curl -s http://localhost:8080/
# {"BTC_USD": 109749.80}

# Test Metrics
curl http://localhost:8080/metrics | grep crypto
# crypto_requests_total 1
# crypto_btc_usd 109749.80

# Go to Prometheus UI → http://localhost:9090/targets and check that crypto-service target is UP.