K8s/Deployment: Update cluster

[caoxianfei1]

Is your feature request related to a problem? (你需要的功能是否与某个问题有关?)

For the way we use Kubernetes API objects, we generally write YAML files corresponding to API objects and hand them over to Kubernetes, which is called declarative API. For declarative APIs, we can change the definition of yaml objects to modify CRD.

Now curve-operator does not support updating Cluster. For example, when we want to add a disk device to the cluster, we will modify the yaml configuration, and then kubectl apply -f cluster.yaml, but it does not support it now. Our operation for apply is in the program will return directly, do not process.

Of course, when other daemon processes change, such as modifying the deployment node of MDS, you need to delete the service on the previous node and restart an MDS process on the new node.

There are several specific scenarios to consider：
1. Cluster image upgrade (image update).
2. Add Disk or delete disk(Add one Chunkserver service or delete one Chunkserver service).
For new drive letters, in this case, all existing services do not need to be processed, only additional chunkserver nodes
need to be added, and for deleting nodes, only the corresponding chunkserver services need to be deleted.
3. Consider adding a new node to deal with ETCD, MDS SnapshotServer offline.

Describe the solution you'd like (描述你期望的解决方法)

We want the operator to have the ability to update the cluster and you can handle it when API Server detects configuration yaml file changed instead of leaving it alone.

Requirement(要求)

1. A design document is needed then to development phase.
2. Code implementation.

[zhanghuidinah]

• This issue has been chosen for community developer activities. Welcome to feel free to try it. After the PR is merged, you will receive a gift package and a certificate as a community contributor.

• Developer Activities Registration Steps please ref [2023 Q2 Developer Activities]: Call For Participation！ curve#2334 (comment)

[MateSousa]

can i try??

[caoxianfei1]

can i try??

ok, we will have a Summer Coding Camp, and you can choose the issue

[peaceLT]

can i try?

[caoxianfei1]

can i try?

All right.

[peaceLT]

hello,I am currently a third-year graduate student majoring in computer technology at the School of Information, Shanghai Ocean University. My main technology stack includes Golang, Kubernetes and Docker. I am very interested in the cloud native field. I chose this topic because it is related to technology and can help improve my technical skills. please assign this issue to me, thanks

[caoxianfei1]

hello,I am currently a third-year graduate student majoring in computer technology at the School of Information, Shanghai Ocean University. My main technology stack includes Golang, Kubernetes and Docker. I am very interested in the cloud native field. I chose this topic because it is related to technology and can help improve my technical skills. please assign this issue to me, thanks

welcome!