Brian Ketelsen

Brian Ketelsen

I'm a cloud advocate focused on the future of distributed computing.

Bash Helpers for Quick Installs

A quick helper function and directory layout for repeatable software installs.

3 minute read

This bash setup is the latest evolution of my quest to make a new system install as fast as possible.

Speed Up Software Installs with this Bash Trick

I’ve created a bash function that enables quick software installs without being as heavy as something like ansible. The system relies on a single function in my bashrc and a directory full of bash scripts. Let’s dive in and see how it works.

Installation Scripts

In my dotfiles directory, which is stored at ~/dotfiles there’s a subdirectory called install. That directory contains a few dozen bash scripts that install the various software components and packages I might use. Some of them are needed on all the computers I use, some of them are used only infrequently for certain projects. Here’s an example that installs Go:

❯ go.sh 
#! /bin/bash
set -e
VERSION=1.15
# Delete existing Go installation
sudo rm -rf /usr/local/go
# Install Go in /usr/local
sudo mkdir -p /usr/local/go && curl -Ls https://storage.googleapis.com/golang/go$VERSION.linux-amd64.tar.gz | sudo tar xvzf - -C /usr/local/go --strip-components=1

The script declares a VERSION variable so I can change the version to be installed when there’s a new release of Go. Then it deletes the existing Go installation and replaces it with a freshly downloaded version. Because it deletes the existing install and replaces it, it can be run more than once with no unwanted side-effects. I’ve attempted to make all my scripts idempotent like this, but some of them just aren’t because my bash skills are just mediocre.

Installation Function

To use these installation scripts I’ve created a bash function that searches for scripts in the ~/dotfiles/install folder matching the first argument of the function:

inst() {
	if [ -f $HOME/dotfiles/install/$1.sh ] ; then
		echo Installing $1
		. $HOME/dotfiles/install/$1.sh	
	else
		echo $1 not found
	fi
}

To install Go using this function I would type $> inst go, which would search for a script called ~/dotfiles/install/go.sh and execute it if it exists. It’s not complicated, and only took a few minutes to write the function, but I’m getting a lot of ROI on the time I spend writing installation scripts. When I spin up a new VM somewhere, I can quickly clone my dotfiles and install just the bits I need for a particular task.

Direnv integration

I’ve been playing with direnv integrations to make the installation of required tools or commands automatic when entering a project directory. I haven’t found anything yet that doesn’t feel too “hacky”, so I haven’t finished this part.

Future Ideas

In the future I may extend the script to search for installation scripts with an arch component in the file path, like ~/dotfiles/install/linux/go.sh or ~/dotfiles/install/macos/go.sh. I don’t have a need for this right now because I’m not using my Mac for development work.

I may also consider making meta scripts that call others. It might be similar to installing a Development metapackage, where the metapackage simply calls the other packages it wants to wrap.

Recent posts

Categories

About

Hard to believe this content is free.