Coinbase DevOps Engineer Coding Questions

Coinbase aims to maintain lightweight Docker images for faster deployment and reduced bandwidth usage.
Problem Statement: Your task is to optimize a given Dockerfile used to build a service image. The goal is to minimize the image size while ensuring that all dependencies are available and the application runs as expected.
Method Signatures:
- def optimize_dockerfile(base_image: str, packages: List[str]) -> str: - Returns an optimized Dockerfile as a string.Example 1:
Input: optimize_dockerfile('python:3.9-slim', ['flask', 'requests'])
Output: "FROM python:3.9-slim\nRUN pip install --no-cache-dir flask requests"
Explanation: Returns an optimized Dockerfile using slim image and no-cache for pip installations.Example 2:
Input: optimize_dockerfile('node:14', ['express', 'body-parser'])
Output: "FROM node:14\nRUN npm install --production"
Explanation: This avoids dev dependencies to keep the image size smaller.Constraints:
- 1 <= base_image.length <= 50
- 1 <= packages.length <= 20 and each package name is at most 30 characters long.

Coinbase relies on efficiently managing deployment pipelines for its microservices architecture to ensure rapid delivery of new features and fixes.
Problem Statement: You are tasked to create a script that automates the CI/CD pipeline for a microservice application. The script should handle tasks such as building Docker images, running tests, and deploying to a specified environment. You should also ensure the script can roll back to the previous version in case of failure.
Method Signatures:
- def build_image(service_name: str) -> None: - Builds the Docker image for the service.
- def run_tests(service_name: str) -> bool: - Runs tests for the service and returns True if all tests pass.
- def deploy(service_name: str, environment: str) -> None: - Deploys the service to the specified environment.
- def rollback(service_name: str) -> None: - Rolls back the deployment to the previous version.Example 1:
Input: build_image('auth_service')
Output: None
Explanation: This should build the Docker image for the auth service.Example 2:
Input: run_tests('auth_service')
Output: True
Explanation: This indicates that all tests for the auth service passed.Constraints:
- 1 <= service_name.length <= 100
- environment must be one of the strings: 'staging', 'production', 'development'.