feat: add kubeblocks component postStart hook demo

[Y-Rookie]

all ENVs can be used in postStart hook script, including:

• the env of the pod corresponding to the component
• the custom envs defined in the postStart hook in clusterDefinition API ,
• as well as some additional envs injected by KubeBlocks, such as KB_CLUSTER_COMPONENT_LIST.

KUBERNETES_SERVICE_PORT_HTTPS=443
PIKA_PIKA_CLUSTER_CODIS_DASHBOARD_PORT=tcp://10.43.254.210:18080
KUBERNETES_SERVICE_PORT=443
PIKA_PIKA_CLUSTER_CODIS_PROXY_PORT_11080_TCP_ADDR=10.43.70.165
PIKA_PIKA_CLUSTER_PIKA_GROUP_2_PORT_9221_TCP=tcp://10.43.145.75:9221
HOSTNAME=kb-poststart-job-pika-pika-cluster-pika-group-1-52sql
PIKA_PIKA_CLUSTER_CODIS_FE_PORT_8080_TCP=tcp://10.43.151.40:8080
PIKA_PIKA_CLUSTER_CODIS_PROXY_PORT_11080_TCP=tcp://10.43.70.165:11080
KB_CLUSTER_UID_POSTFIX_8=6a685428
PIKA_PIKA_CLUSTER_ETCD_SERVICE_PORT_CLIENT=2379
PIKA_PIKA_CLUSTER_CODIS_PROXY_SERVICE_PORT=11080
KB_PODIP=10.42.0.92
PIKA_PIKA_CLUSTER_PIKA_GROUP_1_SERVICE_HOST=10.43.244.2
PIKA_PIKA_CLUSTER_CODIS_DASHBOARD_PORT_18080_TCP_PROTO=tcp
PIKA_PIKA_CLUSTER_PIKA_GROUP_1_PORT=tcp://10.43.244.2:9221
KB_POD_UID=828f2dc5-08b0-4cf1-bb63-5ee2d31c1996
KB_POD_NAME=kb-poststart-job-pika-pika-cluster-pika-group-1-52sql
PWD=/pika
PIKA_PIKA_CLUSTER_CODIS_PROXY_PORT_19000_TCP_PROTO=tcp
PIKA_PIKA_CLUSTER_CODIS_DASHBOARD_PORT_18080_TCP_ADDR=10.43.254.210
PIKA_PIKA_CLUSTER_PIKA_GROUP_1_PORT_9221_TCP_PORT=9221
PIKA_PIKA_CLUSTER_CODIS_PROXY_PORT_19000_TCP_ADDR=10.43.70.165
PIKA_PIKA_CLUSTER_PIKA_GROUP_2_SERVICE_PORT_PIKA=9221
PIKA_BUILD_DIR=/tmp/pika
PIKA_PIKA_CLUSTER_CODIS_FE_PORT_8080_TCP_PROTO=tcp
KB_POD_IPS=10.42.0.92
PIKA_PIKA_CLUSTER_CODIS_PROXY_PORT=tcp://10.43.70.165:11080
PIKA_PIKA_CLUSTER_CODIS_DASHBOARD_PORT_18080_TCP_PORT=18080
PIKA_PIKA_CLUSTER_CODIS_FE_PORT_8080_TCP_PORT=8080
HOME=/root
KB_CLUSTER_NAME=pika-pika-cluster
KUBERNETES_PORT_443_TCP=tcp://10.43.0.1:443
PIKA_PIKA_CLUSTER_ETCD_PORT=tcp://10.43.112.153:2379
PIKA_PIKA_CLUSTER_PIKA_GROUP_1_SERVICE_PORT=9221
PIKA_PIKA_CLUSTER_ETCD_SERVICE_PORT_PEER=2380
PIKA_PIKA_CLUSTER_ETCD_PORT_2380_TCP=tcp://10.43.112.153:2380
PIKA_PIKA_CLUSTER_ETCD_PORT_2379_TCP=tcp://10.43.112.153:2379
PIKA_PIKA_CLUSTER_ETCD_SERVICE_HOST=10.43.112.153
PIKA_PIKA_CLUSTER_ETCD_PORT_2379_TCP_PORT=2379
PIKA_PIKA_CLUSTER_ETCD_PORT_2379_TCP_ADDR=10.43.112.153
PIKA_PIKA_CLUSTER_ETCD_PORT_2380_TCP_PORT=2380
PIKA_PIKA_CLUSTER_CODIS_PROXY_SERVICE_PORT_PROXY=11080
KB_HOST_IP=172.24.0.3
KB_CLUSTER_COMP_NAME=pika-pika-cluster-pika-group-1
KB_SA_NAME=default
PIKA_PIKA_CLUSTER_CODIS_DASHBOARD_SERVICE_PORT_DASHBOARD=18080
KB_NAMESPACE=default
KB_POD_IP=10.42.0.92
PIKA_PIKA_CLUSTER_CODIS_PROXY_PORT_11080_TCP_PROTO=tcp
PIKA_PIKA_CLUSTER_PIKA_GROUP_2_SERVICE_PORT=9221
PIKA_PIKA_CLUSTER_CODIS_FE_SERVICE_PORT=8080
PIKA_PIKA_CLUSTER_CODIS_DASHBOARD_SERVICE_HOST=10.43.254.210
PIKA_PIKA_CLUSTER_CODIS_FE_PORT=tcp://10.43.151.40:8080
PIKA_PIKA_CLUSTER_CODIS_FE_PORT_8080_TCP_ADDR=10.43.151.40
PIKA_PIKA_CLUSTER_PIKA_GROUP_1_PORT_9221_TCP_ADDR=10.43.244.2
PIKA_PIKA_CLUSTER_CODIS_PROXY_SERVICE_HOST=10.43.70.165
PIKA_PIKA_CLUSTER_CODIS_PROXY_SERVICE_PORT_ADMIN=19000
PIKA_PIKA_CLUSTER_CODIS_PROXY_PORT_19000_TCP=tcp://10.43.70.165:19000
PIKA_PIKA_CLUSTER_CODIS_DASHBOARD_SERVICE_PORT=18080
PIKA_PIKA_CLUSTER_PIKA_GROUP_1_PORT_9221_TCP=tcp://10.43.244.2:9221
SHLVL=0
PIKA_PIKA_CLUSTER_ETCD_PORT_2380_TCP_PROTO=tcp
PIKA=/pika
KUBERNETES_PORT_443_TCP_PROTO=tcp
PIKA_PIKA_CLUSTER_CODIS_FE_SERVICE_HOST=10.43.151.40
PIKA_PIKA_CLUSTER_CODIS_PROXY_PORT_11080_TCP_PORT=11080
KUBERNETES_PORT_443_TCP_ADDR=10.43.0.1
PIKA_PIKA_CLUSTER_ETCD_PORT_2379_TCP_PROTO=tcp
PIKA_PIKA_CLUSTER_PIKA_GROUP_2_SERVICE_HOST=10.43.145.75
KB_POD_FQDN=kb-poststart-job-pika-pika-cluster-pika-group-1-52sql.pika-pika-cluster-pika-group-1-headless.default.svc
PIKA_PIKA_CLUSTER_PIKA_GROUP_2_PORT_9221_TCP_PORT=9221
PIKA_PIKA_CLUSTER_CODIS_PROXY_PORT_19000_TCP_PORT=19000
KUBERNETES_SERVICE_HOST=10.43.0.1
KUBERNETES_PORT=tcp://10.43.0.1:443
KB_COMP_NAME=pika-group-1
KUBERNETES_PORT_443_TCP_PORT=443
PIKA_PIKA_CLUSTER_PIKA_GROUP_2_PORT_9221_TCP_PROTO=tcp
PATH=:/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
PIKA_PIKA_CLUSTER_CODIS_DASHBOARD_PORT_18080_TCP=tcp://10.43.254.210:18080
PIKA_PIKA_CLUSTER_ETCD_SERVICE_PORT=2379
PIKA_PIKA_CLUSTER_PIKA_GROUP_2_PORT_9221_TCP_ADDR=10.43.145.75
PIKA_PIKA_CLUSTER_ETCD_PORT_2380_TCP_ADDR=10.43.112.153
KB_PODIPS=10.42.0.92
PIKA_PIKA_CLUSTER_PIKA_GROUP_2_PORT=tcp://10.43.145.75:9221
PIKA_PIKA_CLUSTER_PIKA_GROUP_1_PORT_9221_TCP_PROTO=tcp
PIKA_PIKA_CLUSTER_CODIS_FE_SERVICE_PORT_FE=8080
KB_HOSTIP=172.24.0.3
KB_NODENAME=k3d-pika-server-0
PIKA_PIKA_CLUSTER_PIKA_GROUP_1_SERVICE_PORT_PIKA=9221
_=/bin/env

KB_CLUSTER_COMPONENT_LIST=pika-group-1,pika-group-2,etcd,codis-proxy,codis-fe,codis-dashboard

[machinly]

A new pull request has been submitted, referring to this. #2121