[feature request] Support SidecarSet update strategy when pod recreate or inject

[a630140621]

What would you like to be added:

Support SidecarSet update strategy when pod recreate or inject

Why is this needed:

There are two teams under one organizational structure. Team A maintain SidecarSet. Team B maintain Application which can use Deployment.

Team A inject SidecarSet to Pod which may controlled by Team B. Now, Team A want to update SidecarSet to new version. They use a partition update strategy.

At the same time, Team B want to release a new application version which may fix an emergency bug. Unfortunately, SidecarSet is all new version now.

So, I want to apply update strategy when pod inject.

[a630140621]

Here is an example:

first,

# sidecarset.yaml
apiVersion: apps.kruise.io/v1alpha1
kind: SidecarSet
metadata:
  name: test-sidecarset
spec:
  selector:
    matchLabels:
      sidecarset: test-sidecarset
  updateStrategy:
    type: RollingUpdate
    # type: NotUpdate
    maxUnavailable: 1
    partition: 2
  containers:
    - name: sidecar1
      image: centos:6.7
      command: ["sleep", "999d"] # do nothing at all
      volumeMounts:
        - name: log-volume
          mountPath: /var/log
  volumes: # this field will be merged into pod.spec.volumes
    - name: log-volume
      emptyDir: {}

apiVersion: apps/v1
kind: Deployment
metadata:
  name: test-nginx
spec:
  replicas: 5
  selector:
    matchLabels:
      app: test-nginx
  template:
    metadata:
      labels:
        app: test-nginx
        sidecarset: test-sidecarset
    spec:
      containers:
      - name: test-nginx
        image: nginx:1.15.1
        resources:
          limits:
            memory: "256Mi"
            cpu: "500m"
        ports:
        - containerPort: 10000

now, result is

kubectl get po                                                
NAME                          READY   STATUS    RESTARTS   AGE
test-nginx-778d5db47b-95mwt   2/2     Running   0          7m59s
test-nginx-778d5db47b-9nvvk   2/2     Running   1          7m59s
test-nginx-778d5db47b-vvknk   2/2     Running   0          7m59s
test-nginx-778d5db47b-wk567   2/2     Running   0          7m59s
test-nginx-778d5db47b-x6k8d   2/2     Running   1          7m59s

then, Team A update SidecarSet.

# sidecarset.yaml
apiVersion: apps.kruise.io/v1alpha1
kind: SidecarSet
metadata:
  name: test-sidecarset
spec:
  selector:
    matchLabels:
      sidecarset: test-sidecarset
  updateStrategy:
    type: RollingUpdate
    # type: NotUpdate
    maxUnavailable: 1
    partition: 2
  containers:
    - name: sidecar1
      image: centos:7
      command: ["sleep", "999d"] # do nothing at all
      volumeMounts:
        - name: log-volume
          mountPath: /var/log
  volumes: # this field will be merged into pod.spec.volumes
    - name: log-volume
      emptyDir: {}

result

kubectl get po -o yaml | grep 'image: centos'
image: centos:6.7
image: centos:7
image: centos:6.7
image: centos:7
image: centos:7

at the same time, Team B update Deployment.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: test-nginx
spec:
  replicas: 5
  selector:
    matchLabels:
      app: test-nginx
  template:
    metadata:
      labels:
        app: test-nginx
        sidecarset: test-sidecarset
    spec:
      containers:
      - name: test-nginx
        image: nginx:1.15.1
        resources:
          limits:
            memory: "128Mi"
            cpu: "500m"
        ports:
        - containerPort: 10000

result

kubectl get po -o yaml | grep 'image: centos'
image: centos:7
image: centos:7
image: centos:7
image: centos:7
image: centos:7

expect two centos: 6.7 and three centos: 7

[veophi]

Very Good Issue!

In fact, we have noticed this problem and are solving it. The current progress about the solution is as follows:

• store history revisions for sidecarset #715 has been ready to support the storage of historical revisions of SidecarSet.

• The next plan is to enable users to inject the specified historical version of SidecarSet. (very soon)

[a630140621]

Oh, I notice this #715.

• I want is keep SidecarSet's update strategy even if Pod recreate. They are related but different.
• There are any PR now, otherwise I can contribute one.

[a630140621]

Another issue is the update strategy equal NotUpdate.

I want to apply a new version SidecarSet only if Team B update their application (risk considerations). Of course, new version SidecarSet have some update strategy.

[veophi]

Oh, I notice this #715.

• I want is keep SidecarSet's update strategy even if Pod recreate. They are related but different.
• There are any PR now, otherwise I can contribute one.

• Can you further describe your desired upgrade behavior of SidecarSet?

• We would MOSTLY WELCOME you to contribute your solutions/codes for kruise! Maybe, you can first submit a proposal to describe your solution if you have time.

[zmberg]

#1021