- TOC {:toc}
kompose
has 3 stages: Loader, Transformer and Outputter. Each Stage should have well defined interface so it is easy to write new Loader, Transformer or Outputters and plug it in. Currently only Loader and Transformer interfaces are defined.
Loader reads input file (now kompose
supports Docker Compose v1, v2 and Docker Distributed Application Bundle file) and converts it to KomposeObject.
Loader is represented by a Loader interface:
type Loader interface {
LoadFile(file string) kobject.KomposeObject
}
Every loader “implementation” should be placed into kompose/pkg/loader
(like compose & bundle). More input formats will be supported in future. You can take a look for more details at:
KomposeObject
is Kompose internal representation of all containers loaded from input file. First version of KomposeObject
looks like this (source: kobject.go):
// KomposeObject holds the generic struct of Kompose transformation
type KomposeObject struct {
ServiceConfigs map[string]ServiceConfig
}
// ServiceConfig holds the basic struct of a container
type ServiceConfig struct {
ContainerName string
Image string
Environment []EnvVar
Port []Ports
Command []string
WorkingDir string
Args []string
Volumes []string
Network []string
Labels map[string]string
Annotations map[string]string
CPUSet string
CPUShares int64
CPUQuota int64
CapAdd []string
CapDrop []string
Entrypoint []string
Expose []string
Privileged bool
Restart string
User string
}
Transformer takes KomposeObject and converts it to target/output format (at this moment, there are sets of kubernetes/openshift objects). Similar to Loader
, Transformer is represented by a Transformer interface:
type Transformer interface {
Transform(kobject.KomposeObject, kobject.ConvertOptions) []runtime.Object
}
If you wish to add more providers which contain different kind of objects, transformer would be the place to look into. At this moment Kompose supports Kubernetes (by default) and Openshift providers. More details at:
Outputter takes Transformer result and executes given action. For example action can be displaying result to stdout or directly deploying artifacts to Kubernetes/OpenShift.