engine

Documentation

Overview

Package engine holds code that drive the engine of Kusion.

Kusion Engine is a middle layer between Spec and the actual infrastructure. The major function of this engine is to parse the Spec and to turn all actual infra resources into the desired state described in the Spec and almost all operations from the command line will invoke this engine to finish their jobs.

It consists of 3 parts:

1. Operation Engine: this part is the entrypoint of the whole Kusion Engine and is responsible for kusion basic operations like Preview, Apply, Destroy, etc. The main workflow of this part is to parse resources in the Spec, figure out which resource should be modified according to specified operation type, and execute this operation to the real infra resources. During this workflow, the following two parts will be involved.

2. Runtime: it is an interface between the actual infrastructure and Kusion. All operations that trying to manipulate a resource should be delegated to one Runtime to make this operation effect in the actual infrastructure

3. State: state is a record of an operation's result. It is often used as a datasource for 3-way merge/diff in operations like Apply or Preview

Let's get operation Preview as an example to demonstrate how the three parts cooperate in an actual operation.

                 +-------------+
                 |  Operation  |
                 |  Preview    |
                 +-------------+
                        |
                        |
                 +-------------+
                 |  Operation  |
       +---------|  Engine     |----------+
       |         +-------------+          |
       |                                  |
+-------------+                    +-------------+
|   State     |                    |   Runtime   |
+-------------+                    +-------------+

1. parse resources in the Spec and convert into a DAG

2. Walk this DAG: a) get the latest state from the actual infra by the Runtime b) get last operation state from the State

3. Diff the two states(live state and prior state) and return the details of these diffs to cmd

Index

• Constants
• func BuildIDForKubernetes(apiVersion, kind, namespace, name string) string
• func ConvertKCLResult2Resources(resourceYAMLs []kcl.KCLResult) (*models.Spec, error)
• func NewRequestResourceForKubernetes(r kcl.KCLResult) (*models.Resource, string, error)

Constants

const MaxLogLength = 3751

const (
	Separator = ":"
)

Functions

func BuildIDForKubernetes

func BuildIDForKubernetes(apiVersion, kind, namespace, name string) string

func ConvertKCLResult2Resources

func ConvertKCLResult2Resources(resourceYAMLs []kcl.KCLResult) (*models.Spec, error)

func NewRequestResourceForKubernetes

func NewRequestResourceForKubernetes(r kcl.KCLResult) (*models.Resource, string, error)