add post-install snippet

Author: nicolaven

README.md

@@ -47,7 +47,30 @@ Note: *while almost all components are under the Apache2 license, only **[Promet
 
 ## How to install it
 
-You can simply use the post-install script that you can find [here](https://github.com/aws-samples/aws-parallelcluster-monitoring/blob/main/post-install.sh) as it is, or customize it as you need. For instance, you might want to change your [Grafana password](https://github.com/aws-samples/aws-parallelcluster-monitoring/blob/main/docker-compose/docker-compose.master.yml#L43) to something more secure and meaningful for you, or you might want to customize some dashboards by adding additional components to monitor. 
+You can simply use the post-install script that you can find [here](https://github.com/aws-samples/aws-parallelcluster-monitoring/blob/main/post-install.sh) as it is, or customize it as you need. For instance, you might want to change your [Grafana password](https://github.com/aws-samples/aws-parallelcluster-monitoring/blob/main/docker-compose/docker-compose.master.yml#L43) to something more secure and meaningful for you, or you might want to customize some dashboards by adding additional components to monitor.
+```
+#Load AWS Parallelcluster environment variables
+. /etc/parallelcluster/cfnconfig
+
+#get git-hib repo to clone and the installation script
+github_repo=$(echo ${cfn_postinstall_args}| cut -d ',' -f 1 )
+setup_command=$(echo ${cfn_postinstall_args}| cut -d ',' -f 2 )
+monitoring_dir_name=$(basename -s .git ${github_repo})
+
+case ${cfn_node_type} in
+    MasterServer)
+        cd /home/$cfn_cluster_user/
+        git clone ${github_repo}
+    ;;
+    ComputeFleet)
+    
+    ;;
+esac
+
+#Execute the monitoring installation script
+bash -x "/home/${cfn_cluster_user}/${monitoring_dir_name}/parallelcluster-setup/${setup_command}" >/tmp/monitoring-setup.log 2>&1
+exit $?
+``` 
 The proposed post-install script will take care of installing and configuring everything for you through the [install-monitoring.sh](https://github.com/aws-samples/aws-parallelcluster-monitoring/blob/main/parallelcluster-setup/install-monitoring.sh) script. Though, few additional parameters are needed in the AWS ParallelCluster config file: the post_install_args, additional IAM policies, security group, and a tag. You can find an AWS ParallelCluster template [here](https://github.com/aws-samples/aws-parallelcluster-monitoring/blob/main/parallelcluster-setup/pcluster-template.config). Please note that, at the moment, the installation script has only been tested using [Amazon Linux 2](https://aws.amazon.com/amazon-linux-2/).
 
 ```