Best Practices and Tips for Writing a Dockerfile
Blog post from Qovery
Dockerfiles are a key component in creating Docker images, serving as a set of instructions that dictate how an image is built, with the syntax relying on specific capitalized keywords like FROM, COPY, and RUN. Best practices for writing Dockerfiles include minimizing image size by removing unnecessary dependencies, using COPY over ADD to reduce ambiguity, and ensuring reproducibility by specifying exact package versions. Security is emphasized through active vulnerability scanning and securing credentials by injecting them at runtime rather than embedding them in the image. Additionally, running containers as non-root users enhances security by reducing the risk of exploitation, and version control helps in tracking changes to Dockerfiles. Dockerfiles should be kept stateless and reproducible, avoiding side effects during builds. Tools like Qovery can streamline deploying these Dockerfiles to cloud platforms like AWS, reducing the need for manual server maintenance.