WIP Add ANP upgrade doc

cmd/cluster-proxy/main.go

@@ -21,6 +21,7 @@ import (
 )
 
 func main() {
+	fmt.Println("cluster-proxy")
 	rand.Seed(time.Now().UTC().UnixNano())
 
 	klog.InitFlags(nil)

dependencymagnet/apiserver-network-proxy/how-to-update-anp.md

@@ -0,0 +1,49 @@
+The cluster-proxy-addon is using a customized version apiserver-network-proxy. The repo(https://github.com/stolostron/apiserver-network-proxy) is forked from the upstream repo: [apiserver-network-proxy](https://github.com/kubernetes-sigs/apiserver-network-proxy/tree/v0.1.10).
+
+And the ANP repo is depending on the repo(https://github.com/stolostron/grpc-go/blob/master/go.mod)
+
+If you need to update the apiserver-network-proxy version, you can follow the steps below:
+
+### 1. git clone the forked repos
+```bash
+git clone [email protected]:stolostron/apiserver-network-proxy.git
+git clone [email protected]:stolostron/dependency-magnet.git
+```
+
+### 2. When need to update the dependencies
+
+When we need to upgrade the go version, the too old version of go will cause the some build jobs failed.
+
+The commit id of the customized code can be found in:
+* https://github.com/kubernetes-sigs/apiserver-network-proxy/commit/d562699c78201daef7dec97cd1847e5abffbe2ab
+* https://github.com/grpc/grpc-go/commit/72dd3e65ac56e8d6b1c6a7ad25404022f1cc7a0a
+
+First under anp project, run:
+
+```
+git fetch upstream
+git branch -r
+git tag -l
+```
+
+Choose the appropriate tag and branch to update. For example, tag `v0.31.1`.
+
+```
+git checkout v0.31.1
+```
+
+The find which version of grpc-go is using in the anp project, in the following file, the version of grpc-go is `v1.67.1`.
+
+```
+➜  apiserver-network-proxy git:(konnectivity-client/v0.31.1) cat go.mod | grep grpc
+        google.golang.org/grpc v1.67.1
+```
+
+Then go to grpc-go project, and checkout the tag `v1.67.1`.
+
+```
+git fetch upstream
+git branch -r
+git tag -l
+git checkout v1.67.1
+```