Common Delegate Scripts

You can use the delegate INIT_SCRIPT environment variable to run startup scripts on the host, container, or pod on installation or restart.

For information on using the INIT_SCRIPT environment variable to run scripts, go to Run Initialization Scripts on Delegates.

This topic provides information on script availability and some common delegate scripts you can declare in the INIT_SCRIPT environment variable.

Utilities

The delegate ships with tar and cURL. To use other utilities you'll need to add them to the beginning of your scripts.

For example, for unzip and wget:

microdnf install unzip  
microdnf install wget  
...

Terraform

# Install TF  
microdnf install unzip
curl -O -L https://releases.hashicorp.com/terraform/1.3.5/terraform_1.3.5_darwin_amd64.zip
unzip terraform_1.3.5_darwin_amd64.zip
mv ./terraform /usr/bin/
# Check TF install
terraform --version

Upgrade Terraform

##terraform update  
microdnf install unzip  
microdnf install wget  
set +x  
apt-get update  
apt-get install wget  
apt-get -y install git  
wget https://releases.hashicorp.com/terraform/1.1.9/terraform_1.3.5_darwin_amd64.zip apt-get install unzip  
unzip terraform_1.3.5_darwin_amd64.zip  
cp terraform /usr/bin/  
terraform --version

Install Terraform and Terragrunt

#Terraform  
microdnf install unzip
curl -O -L https://releases.hashicorp.com/terraform/1.3.5/terraform_1.3.5_darwin_amd64.zip
unzip terraform_1.3.5_darwin_amd64.zip
mv ./terraform /usr/bin/
# Check TF install
terraform --version 
  
#Terragrunt  
microdnf install unzip  
microdnf install wget  
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 3

You do not need to use the INIT_SCRIPT environment variable for Helm 3. Harness provides support for Helm 3 for delegates that connect to the target Kubernetes cluster.

For more information, go to 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  
microdnf install unzip  
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 7 only. Go to 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, go to 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). Go to Install PowerShell Easily via Snap in Ubuntu 18.04.

Import a Self-Signed Certificate

Go to Add Self-Signed Certificates for Delegate Connections.