Common Delegate Scripts

Updated 3 weeks ago by Michael Cretzman

A Delegate INIT environment variable enables you to run a startup script on the host/container/pod for a Harness Delegate when the Delegate is installed or restarted.

For information on Delegate INIT, see Run Initialization Scripts on Delegates.

This topic provides information on script availability and some common Delegate INIT scripts.

Terraform

# Install TF
curl -O -L https://releases.hashicorp.com/terraform/0.12.25/terraform_0.12.25_linux_amd64.zip
unzip terraform_0.12.25_linux_amd64.zip
yes | mv ./terraform /usr/bin/
# Check TF install
terraform --version

Upgrade to Terraform_0.13.3

##terraform update
set +x
apt-get update
apt-get install wget
apt-get -y install git
wget https://releases.hashicorp.com/terraform/0.13.3/terraform_0.13.3_linux_amd64.zip apt-get install unzip
unzip terraform_0.13.3_linux_amd64.zip
cp terraform /usr/bin/
terraform --version

Install Terraform_0.13.3 and Terragrunt

#Terraform
curl -O -L https://releases.hashicorp.com/terraform/0.13.3/terraform_0.13.3_linux_amd64.zip
unzip terraform_0.13.3_linux_amd64.zip
yes | mv ./terraform /usr/bin/
# Check TF install
terraform --version

#Terragrunt
wget https://github.com/gruntwork-io/terragrunt/releases/download/v0.28.0/terragrunt_linux_amd64
yes | mv terragrunt_linux_amd64 terragrunt
chmod u+x terragrunt
yes | mv terragrunt /usr/local/bin/terragrunt
terragrunt --version

Helm 2

Installing Helm and Tiller in the Delegate's cluster:

If you are using remote Helm charts in your Harness Kubernetes Service, you can use the helm init --client-only option, as Tiller is not needed. See Helm charts for more information.
# Add the Helm version that you want to install
HELM_VERSION=v2.14.0
# v2.13.0
# v2.12.0
# v2.11.0

export DESIRED_VERSION=${HELM_VERSION}

echo "Installing Helm $DESIRED_VERSION ..."

curl https://raw.githubusercontent.com/kubernetes/helm/master/scripts/get | bash

# If Tiller is already installed in the cluster
helm init --client-only

# If Tiller is not installed in the cluster
# helm init
DESIRED_VERSION is used by a function in the Helm install script.

If Helm is being installed in a cluster outside of the Delegate's cluster ensure that the kubeconfig in the Delegate cluster is pointing to the correct cluster using:

kubectl config current-context cluster_name
If you are using TLS for communication between Helm and Tiller, ensure that you use the --tls parameter with your commands. For more information, see Command Flags in Helm Deploy step in the Helm Deployment guide, and see  Using SSL Between Helm and Tiller from Helm, and the section Securing your Helm Installation in that document.

Here is an example of how to add a Helm chart from a private repo using secrets repoUsername and repoPassword from Harness Secrets Management.

# Other installation method
# curl https://raw.githubusercontent.com/helm/helm/master/scripts/get > get_helm.sh
# chmod 700 get_helm.sh
# ./get_helm.sh

curl https://raw.githubusercontent.com/helm/helm/master/scripts/get | bash

helm init --client-only

helm repo add --username ${secrets.getValue("repoUsername")} --password ${secrets.getValue("repoPassword")} nginx https://charts.bitnami.com/bitnami

helm repo update

Helm 3

You do not need to add a Delegate INIT for Helm 3. Harness includes Helm 3 support in any Delegate that can connect to the target Kubernetes cluster.

For more information, see Upgrade to Helm 3 Charts in Kubernetes Services and Upgrade Native Helm 2 Deployments to Helm 3.

Pip

Ensure that you run apt-get update before running any apt-get commands.
apt-get update
# Install pip
apt-get -y install python-pip
# Check pip install
pip -v

Unzip

Ensure that you run apt-get update before running any apt-get commands.
apt-get update
# Install Unzip
apt-get install unzip

AWS CLI

The following script installs the AWS CLI version 2 on the Delegate host.

# Install AWS CLI
curl "https://awscli.amazonaws.com/awscli-exe-linux-x86_64.zip" -o "awscliv2.zip"
unzip awscliv2.zip
./awscli-bundle/install -b ~/bin/aws
# install
sudo ./aws/install
# Check AWS CLI install
aws --version

AWS Describe Instance

The following script describes the EC2 instance based on its private DNS hostname, which is also the name in the Delegate's Hostname field:

aws ec2 describe-instances --filters "Name=network-interface.private-dns-name,Values=ip-10-0-0-205.ec2.internal" --region "us-east-1"

The value for the Values parameter is simply the Hostname of the Delegate.

AWS List All Instances in a Region

The following script will list all of the EC2 instances in the region you supply:

aws ec2 describe-instances --query 'Reservations[*].Instances[*].[InstanceId,State.Name,InstanceType,PrivateIpAddress,PublicIpAddress,Tags[?Key==`Name`].Value[]]' --region "us-east-1" --output json | tr -d '\n[] "' | perl -pe 's/i-/\ni-/g' | tr ',' '\t' | sed -e 's/null/None/g' | grep '^i-' | column -t

Git CLI

Ensure that you run apt-get update before running any apt-get commands.
apt-get update
# Install Git with auto approval
yes | apt-get install git
# Check git install
git --version

Cloud Foundry CLI

Harness supports Cloud Foundry CLI version 6 only. Support for version 7 is pending.

See Install Cloud Foundry CLI Versions on the Harness Delegate.

Docker Installation

To install Docker on the Delegate, use the following script:

apt-get update
apt-get install -y apt-utils dnsutils docker
Ensure that you run apt-get update before running any apt-get commands.

PowerShell

You can run PowerShell scripts on a Harness Delegate, even though the Delegate must be run on Linux. Linux supports PowerShell using PowerShell core.

For steps on creating your script, see Installing PowerShell on Linux from Microsoft.

Whatever scripts you run must be supported by the version of PowerShell you install.

Here is an example for Ubuntu 16.04:

# Download the Microsoft repository GPG keys
wget -q https://packages.microsoft.com/config/ubuntu/16.04/packages-microsoft-prod.deb

# Register the Microsoft repository GPG keys
sudo dpkg -i packages-microsoft-prod.deb

# Update the list of products
sudo apt-get update

# Install PowerShell
sudo apt-get install -y powershell

# Start PowerShell
pwsh

If apt-get is not installed on your Delegate host, you can use snap (snap install powershell --classic). See Install PowerShell Easily via Snap in Ubuntu 18.04.

Import a Self-Signed Certificate

See Add Self-Signed Certificates for Delegate Connections.


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