Inject Sidecar Container

 1apiVersion: kyverno.io/v1
 2kind: ClusterPolicy
 3metadata:
 4  name: inject-sidecar
 5  annotations:
 6    policies.kyverno.io/title: Inject Sidecar Container
 7    policies.kyverno.io/category: Sample
 8    policies.kyverno.io/subject: Deployment,Volume
 9    policies.kyverno.io/minversion: 1.6.0
10    policies.kyverno.io/description: >-
11      The sidecar pattern is very common in Kubernetes whereby other applications can
12      insert components via tacit modification of a submitted resource. This is, for example,
13      often how service meshes and secrets applications are able to function transparently.
14      This policy injects a sidecar container, initContainer, and volume into Pods that match
15      an annotation called `vault.hashicorp.com/agent-inject: true`.
16spec:
17  rules:
18  - name: inject-sidecar
19    match:
20      any:
21      - resources:
22          kinds:
23          - Deployment
24    mutate:
25      patchStrategicMerge:
26        spec:
27          template:
28            metadata:
29              annotations:
30                (vault.hashicorp.com/agent-inject): "true"
31            spec:
32              containers:
33              - name: vault-agent
34                image: vault:1.5.4
35                imagePullPolicy: IfNotPresent
36                volumeMounts:
37                - mountPath: /vault/secrets
38                  name: vault-secret
39              initContainers:
40              - name: vault-agent-init
41                image: vault:1.5.4
42                imagePullPolicy: IfNotPresent
43                volumeMounts:
44                - mountPath: /vault/secrets
45                  name: vault-secret
46              volumes:
47              - name: vault-secret
48                emptyDir:
49                  medium: Memory