Welcome to my Reusable Bicep Modules pages!

This project is an effort to create reusable Bicep modules. Focus lies on researching reuse, not on actually creating a library.

Abstract

This is a collection of ideas on how to create reusable Bicep modules. Currently, these are the basic concepts:

use two layers: assemblers and core modules
expose template fragments as parameters instead of single values
during assembly of a resource:
- use Bicep’s union() function to inject references to other resources
- use Bicep’s ternary operator ? to deal with optional assignments of other resources
use the Azure resource types and namespace hierarchy to shape the modules

Background and Motivation

Bicep is a big improvement compared to directly deploying ARM templates. Apart from being much more readable, it wants us to reuse stuff by introducing modules. But as it turned out during the last 2 years, real reuse still is quite hard to achieve.

I think that reusability cannot be achieved by specifying parameters as primitive values.

Why is this not a good idea:

there will be too many of them
they are out of context
adding one, changes the module’s signature and causes breaking changes

The last point is the most important one as it is the death of reuse.

The solution described here exposes template fragments as parameters. Maybe this is also not ideal for other reasons. Nevertheless, I gave this a try and share the results here.

The repository on which this site is based, contains the current state of the implementation.

design decisions describes the approach
deployment describes how the deployment to Azure works
implementations goes into implementation details of selected modules

Currently, the NIC assembler is the most complex one as it assembles a lot of resources and solves the problem of optionally assigning resources. It also lets you choose between assigning existing or newly created resources for assignment. A detailed description of its code is here. Other assemblers still habe to be leveled up.

Currently Available Modules

Here’s a list of the currently available modules and their reuse by parent-modules:

public IP address (pip)
network security group (nsg)
- child: security rules (nsgsr)
network interface card (nic)
- reference: virtual network (vnet)
- reference: subnet (snet)
- reference: public IP address (pip)
- reference: network security group (nsg)
virtual network (vnet)
- child: subnet (snet)
virtual network peering (vnet-peer)
virtual machine (vm)
- reference: network interface card (nic)
storage account (st)
- child: blob services/containers

Valuable Links

A small collection of links on Bicep that I found very helpful:

Alex Chzhen’s blog posts on IaC
- if he explains a topic, you will be hard pressed to find better explanations elsewhere
Eduard Keilholz’s post on creating a bicep library
- this post triggert me into thinking more about reusing Bicep
Getting Started with Azure Bicep (Step-by-Step)
- “Adam the Author” - I love this site
John Savill - Understanding and Using Project Bicep
- John Savill’s introduction to the Bicep project on YouTube

This is only a small and very personal selection. The Microsoft documentation is very good and there are a number of great books on Bicep available by now.

Utility commands

// What is my current tenant:
az account show

// list all my accouts
az account list
// attach a default subscription to an account
az account set --subscription <my subscription>

Disclaimer

Things to notice:

I am by no means a Bicep-professional (experience comes from 2 years of Bicep in a large, real-life project)
My company MT-itsolutions favors Terraform over Bicep for reasons I will not discuss here
- That’s one reason why I’m posting this in a personal repo
My company MT-itsolutions is not to blame for my follies
- I am to blame for any nonsense and all errors published on this site
You are using this repo at your own risk
- I take no responsibility for any damage caused by code published here
This is my first take on GitHub Pages, and I’m not a frontend guy - have mercy