Built-in Policy Type

This documentation will walk through the built-in policies.

apply-once

Overview

Allow configuration drift for applied resources.

Parameter

Name	Type	Description
enable	bool	If true, allow configuration drift.

Example

apiVersion: core.oam.dev/v1beta1

kind: Application

metadata:

name: apply-once-app

spec:

components:

- name: hello-world

type: webservice

properties:

image: oamdev/hello-world

traits:

- type: scaler

properties:

replicas: 1

policies:

- name: apply-once

type: apply-once

properties:

enable: true

garbage-collect

Overview

Configure the garbage collection behaviour for the application.

Parameter

Name	Type	Description
keepLegacyResource	bool	If true, outdated versioned resourcetracker will not be recycled automatically. Outdated resources will be kept until resourcetracker be deleted manually.
rules	[]GarbageCollectPolicyRule	A list of rules to control gc strategy at resource level, if one resource is controlled by multiple rules, first rule will be used.

GarbageCollectPolicyRule

Name	Type	Description
selector	GarbageCollectPolicyRuleSelector	Select the target resources of the rule.
strategy	String	The strategy for target resources to recycle. Available values: never, onAppDelete, onAppUpdate.

GarbageCollectPolicyRuleSelector

Name	Type	Description
componentNames	[]String	Select target resources by component names.
componentTypes	[]String	Select target resources by component types.
traitTypes	[]String	Select target resources by trait types.

Example

apiVersion: core.oam.dev/v1beta1

kind: Application

metadata:

name: first-vela-app

spec:

components:

- name: express-server

type: webservice

properties:

image: oamdev/hello-world

port: 8000

traits:

- type: ingress-1-20

properties:

domain: testsvc.example.com

http:

"/": 8000

policies:

- name: keep-legacy-resource

type: garbage-collect

properties:

keepLegacyResource: true

apiVersion: core.oam.dev/v1beta1

kind: Application

metadata:

name: garbage-collect-app

spec:

components:

- name: hello-world-new

type: webservice

properties:

image: oamdev/hello-world

traits:

- type: expose

properties:

port: [8000]

policies:

- name: garbage-collect

type: garbage-collect

properties:

rules:

- selector:

traitTypes:

- expose

strategy: onAppDelete

Override

Overview

Describe the configuration to override when deploying resources.

Parameter

Name	Type	Description
components	[]ComponentPatch	A list of component configurations to override.
selector	[]String	A list of component names to use. If not set, all components will be used.

ComponentPatch

Name	Type	Description
name	string	The name of the component to override. If not set, it will match all components with the specified type. Can be used with wildcard * for fuzzy match.
type	String	The type of the component to override. If not set, all component types will be matched.
properties	Object	The component properties to merge.
traits	[]TraitPatch	A list of trait configurations to override.

TraitPatch

Name	Type	Description
type	String	The type of the trait to override.
properties	Object	The trait properties to merge.
disable	bool	If true, this trait will be removed.

Examples

apiVersion: core.oam.dev/v1beta1

kind: Application

metadata:

name: deploy-with-override

namespace: examples

spec:

components:

- name: nginx-with-override

type: webservice

properties:

image: nginx

policies:

- name: topology-hangzhou-clusters

type: topology

properties:

clusterLabelSelector:

region: hangzhou

- name: topology-local

type: topology

properties:

clusters: ["local"]

namespace: examples-alternative

- name: override-nginx-legacy-image

type: override

properties:

components:

- name: nginx-with-override

properties:

image: nginx:1.20

- name: override-high-availability

type: override

properties:

components:

- type: webservice

traits:

- type: scaler

properties:

replicas: 3

workflow:

steps:

- type: deploy

name: deploy-local

properties:

policies: ["topology-local"]

- type: deploy

name: deploy-hangzhou

properties:

policies: ["topology-hangzhou-clusters", "override-nginx-legacy-image", "override-high-availability"]

apiVersion: core.oam.dev/v1beta1

kind: Application

metadata:

name: advance-override

namespace: examples

spec:

components:

- name: nginx-advance-override-legacy

type: webservice

properties:

image: nginx:1.20

- name: nginx-advance-override-latest

type: webservice

properties:

image: nginx

policies:

- name: topology-hangzhou-clusters

type: topology

properties:

clusterLabelSelector:

region: hangzhou

- name: topology-local

type: topology

properties:

clusters: ["local"]

namespace: examples-alternative

- name: override-nginx-legacy

type: override

properties:

selector: ["nginx-advance-override-legacy"]

- name: override-nginx-latest

type: override

properties:

selector: ["nginx-advance-override-latest", "nginx-advance-override-stable"]

components:

- name: nginx-advance-override-stable

type: webservice

properties:

image: nginx:stable

workflow:

steps:

- type: deploy

name: deploy-local

properties:

policies: ["topology-local", "override-nginx-legacy"]

- type: deploy

name: deploy-hangzhou

properties:

policies: ["topology-hangzhou-clusters", "override-nginx-latest"]

topology

Overview

Describe the destination where components should be deployed to.

Parameter

Name	Type	Description
clusters	[]string	The names of the clusters to select.
clusterLabelSelector	mpa[string]string	The label selector for clusters. Exclusive to "clusters"
namespace	string	The target namespace to deploy in the selected clusters. If not set, components will inherit the original namespace.

Example

apiVersion: core.oam.dev/v1beta1

kind: Application

metadata:

name: basic-topology

namespace: examples

spec:

components:

- name: nginx-basic

type: webservice

properties:

image: nginx

policies:

- name: topology-hangzhou-clusters

type: topology

properties:

clusters: ["hangzhou-1", "hangzhou-2"]

apiVersion: core.oam.dev/v1beta1

kind: Application

metadata:

name: label-selector-topology

namespace: examples

spec:

components:

- name: nginx-label-selector

type: webservice

properties:

image: nginx

policies:

- name: topology-hangzhou-clusters

type: topology

properties:

clusterLabelSelector:

region: hangzhou

apiVersion: core.oam.dev/v1beta1

kind: Application

metadata:

name: local-ns-topology

namespace: examples

spec:

components:

- name: nginx-local-ns

type: webservice

properties:

image: nginx

policies:

- name: topology-local

type: topology

properties:

clusters: ["local"]

namespace: examples-alternative