sidecar-injector

Need to update the license file

Prerequisites

1. Ensure that the kubernetes cluster has at least 1.9 or above.
2. Ensure that MutatingAdmissionWebhook controllers are enabled
3. Ensure that the admissionregistration.k8s.io/v1beta1 API is enabled

Verification:

kubectl api-versions | grep admissionregistration.k8s.io/v1beta1

The output should be:

admissionregistration.k8s.io/v1beta1

OR

ps -ef | grep kube-apiserver | grep admission-control

Output should be:

--admission-control=NamespaceLifecycle,LimitRanger,ServiceAccount,DefaultStorageClass,DefaultTolerationSeconds,NodeRestriction,MutatingAdmissionWebhook,ValidatingAdmissionWebhook,ResourceQuota

Build

1. Setup dependency

   The repo uses gvt as the dependency management tool for its Go codebase. Install gvt by the following command:

go get -u github.com/FiloSottile/gvt

2. Build binary, image and push to docker hub

1. setup a GOPATH

2. bash -x build.sh

Deploy

bash -x deploy.sh

Verify

1. The sidecar injector webhook should be running

[root@mstnode ~]# kubectl get pods -n mutation
NAME                                                          READY     STATUS    RESTARTS   AGE
sidecar-injector-webhook-mesher-deployment-8576646db8-x6f56   1/1       Running   0          20s

[root@mstnode ~]# kubectl get deployment -n mutation
NAME                                         DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
sidecar-injector-webhook-mesher-deployment   1         1         1            1           1m

2. Label the mutation namespace with sidecar-injector=enabled

kubectl label namespace mutation sidecar-injector=enabled
[root@mstnode ~]# kubectl get namespace -L sidecar-injector
NAME          STATUS    AGE       SIDECAR-INJECTOR
default       Active    18h
kube-public   Active    18h
kube-system   Active    18h
mutation      Active    3m        enabled

3. Deploy an app in Kubernetes cluster, take client app as an example

[root@mstnode ~]# cat <<EOF | kubectl create -f -
apiVersion: v1
kind: Pod
metadata:
  name: client
  namespace: mutation
  annotations:
    sidecar-injector-mesher.io/inject: "yes"
  labels:
    app: client
    version: 0.0.1
spec:
  containers:
    - name: client
      image: xiaoliang/client-go
      env:
        - name: TARGET
          value: http://server-mesher/
        - name: http_proxy
          value: http://127.0.0.1:30101/
      ports:
        - containerPort: 9000
EOF

4. Verify sidecar container injected

[root@mstnode ~]# kubectl get pods -n mutation
NAME                                                          READY     STATUS    RESTARTS   AGE
client                                                        2/2       Running   0          12s

Clean

bash -x clean.sh