Authentication

Authentication on the web often feels confusing not because it is complicated, but because its core ideas are rarely explained in a clean order. This post builds that order. We will start from the nature of the web itself, explain cookies and server-side sessions as a single coherent model, then expand outward to JWT and why it fits modern distributed systems. The goal is not to overwhelm you, but to give you a mental model you can reuse. ...

If you build your own container manage system when integrating docker client library, you may also encounter issues with credential resolution. If you system maintain the registry credential, it is easy to assume that authentication will “just work” once credentials are configured in your platform. But behind the scenes, Docker follows a specific and sometimes confusing logic for how it locates and uses credentials. This post explains that behavior in depth and highlights one of the most common causes of authentication issues developers face when using the Docker client as part of a backend or automation workflow. ...

The Problem I’m building a container management tool using the Docker Compose SDK (link) and the Docker CLI library (link). One feature is the ability to deploy Docker Compose YAML files that reference images from private registries. To handle authentication, I added private registry credentials into my tool and injected them into the Docker client using the authConfig field during Compose service initialization. I expected Docker Compose to use these credentials when pulling images. ...