Deis consists of a number of components that combine to create a distributed PaaS. Each Deis component is deployed as a container or set of containers.
The controller component is an HTTP API server. Among other functions, the
controller contains the scheduler, which decides
where to run app containers.
deis command-line client interacts with this component.
Caching can cause problems for
deis pull, but may speed up access to small
files when using a remote storage backend such as S3. The
tool does not install or start the cache by default.
- Receives incoming
git pushrequests over SSH
- Authenticates the user via SSH key fingerprint
- Authorizes the user’s access to write to the Git repository
- Builds a new Docker image from the updated git repository
- Adds the latest Config to the resulting Docker image
- Pushes the new Docker image to the platform’s Registry
- Triggers a new Release through the Controller
The builder component does not incorporate Config directly into the images it produces. A Release is a pairing of an application image with application configuration maintained separately in the Deis Database.
Once a new Release is generated, a new set of containers is deployed across the platform automatically.
The logspout component is a customized version of progrium’s logspout that runs on all CoreOS hosts in the cluster and collects logs from running containers. It sends the logs to the Logger component.
The publisher component is a microservice written in Go that publishes containers to etcd so they can be exposed by the platform Router.