OpenTofu Registry Guide: Tips, Examples, and Ways to Contribute

In December 2023, alongside the 1.6 beta release of OpenTofu, we launched the initial version of its public registry, inspired by  Homebrew to provide easy access to all Terraform/OpenTofu-compatible providers and modules.

The initial registry version was well-received and quickly adopted. However, we had a bigger vision for its future, including a graphic UI layer to enhance the developer experience and provide easy access to information, to support implementing Infrastructure as Code with OpenTofu.

This week, that vision became a reality with the launch of search.OpenTofu.org, bringing the user-friendly UI we had envisioned in the earlier days of the project. And we are happy to report that it looks great!

The registry UI release is a key milestone in OpenTofu's journey, and you are welcome to check out the official post to learn more about it and the road ahead. 

To mark this occasion, we’ll use the rest of this post to provide a brief guide to the new OpenTofu Registry UI, explore its use cases, highlight key features, and give an example of how it can be used.

Why Do We Need a Registry UI?

The primary motivation for having a UI for a registry is, of course, to enhance the experience for developers building with OpenTofu, particularly those new to the OpenTofu/Terraform ecosystem.

The registry is, in essence, a huge centralized hub for all module and provider information. A huge ‘phonebook’ if you will, where developers can easily find details about each component and quickly start using it, leveraging quick access to documentation, examples, and guidance.

With this in mind, let’s quickly go over the key registry features, each designed to give OpenTofu users easy access to the most relevant, curated information they need to build with confidence.

Search Functionality 

The search experience is at the core of the registry, serving as a delivery mechanism for the information you’ll need, which covers the following types of assets:

• Providers: The plugins used to make API calls by OpenTofu to interact with major cloud providers, such as GCP, AWS, and Azure.
• Resources: The infrastructure components, such as compute servers and networking.  
• Modules: The reusable bundles of configurations and resources in Terraform that follow the DRY (Don’t Repeat Yourself) principle.

Using the search function puts you just a few clicks away from the information you need to start using the above components correctly.

Provider Documentation 

Next, let’s look at the provider documentation page, taking the example of the official AWS provider shown in the screenshot below:

As you can see, the page provides an abundance of information, presented concisely and efficiently. Let’s zoom in on a few key sections. 

• 'Overview' on the left is a collection of various resources, data sources, and functions to help you write IaC code for configuring and deploying AWS services.
• ‘Versions’ links, on the right, act as a quick way to browse through previous provider iterations. As you do, please note the changes in ‘Overview’, which will auto-update to hold information relevant to the specific version you’ve selected. 
• ‘Repository’ and ‘License’ sections below provide additional important information and a shortcut to the official Github repo. 
• The center of the page shows the documentation itself, provided by the official maintainer. 

Module Documentation 

Next, let's take a quick look at the other type of documentation in the registry: OpenTofu-compatible modules.

For this, we'll use the example of the ‘cloudposse/s3-bucket’, which, as the name suggests, is a module used for deploying S3 buckets and maintained by CloudPosse.

Again, let’s break down the various sections on the page. On the left, you’ll see links to several sub-sections:

• ‘Readme’ provides general information and some usage examples.
• ‘Inputs‘ details the mandatory and optional input arguments used to configure the module.
• ‘Outputs‘ shows the outputs, such as [.code]bucket_arn[.code], which are generated after the bucket is created and can be referenced by other resources and modules (learn more about output piping in env0).
• ‘Dependencies‘ describes the resources or modules on which this module depends, such as the S3 user for the bucket.
• ‘Resources‘ lists the resources that might be deployed with the module, each having a unique address based on the inputs. For instance, the 's3-bucket' module will deploy resources like aws_s3_bucket.default.

The sections on the right are similar to those found in the provider documentation pages. Here, once again, it's important to note the version and license information.

Example: Using OpenTofu Registry with env0 Provider

To quickly demonstrate how registry information could be useful, here’s a step-by-step guide to using the env0 OpenTofu/Terraform provider:

Step 1: Search env0 Provider

Open the search, type in “env0” and choose the first option. Note the maintainer here is env0, which means that this is the official version.

Clicking on the result will get you to the documentation page, where you can copy the “How to use” code snippet, shown here:

Step 2: Initialize the Provider

Using the example snippet and other documentation, configure the provider in your .tf file, like so:

terraform {
  required_providers {
    env0 = {
      source = "env0/env0"
    }
  }
}
provider "env0" {
}

Run the [.code]tofu init[.code] command in your terminal to receive this output:

(base) ➜  env0 git:(main) ✗ tofu init
Initializing the backend...
Initializing provider plugins...
- Finding latest version of env0/env0...
- Installing env0/env0 v1.20.9...
- Installed env0/env0 v1.20.9 (signed, key ID 14177437C817FE73)
…
OpenTofu has been successfully initialized!

Step 3: Deploy AWS Resources

Now, with the env0 provider initialized, select a resource you want to deploy using the env0 provider.

For example, to create ‘aws_credentials’, select that resource in the left sidebar:

Inside you will find the documentation with three sections:

• ‘Example Usage’  shows a pre-configured resource block for [.code]aws_credentials[.code].
• ‘Schema’ displays the input arguments for a resource, which could be mandatory (required), optional, or read-only.
• ‘Import’ provides you with the import commands that help you bring your existing [.code]aws_credentials[.code] resource, which was created manually, under your OpenTofu state.

Use the ‘Example Usage’ code and configure your resource, updating the example with actual fields (e.g., replacing the “your arn” below). Run the [.code]tofu apply[.code] command to deploy your resources within your infrastructure.
The output you should see is:

(base) ➜  env0 git:(main) ✗ tofu plan
…
  + resource "env0_aws_credentials" "credentials" {
      + arn  = "your arn"
      + id   = (known after apply)
      + name = "env0"
    }
Plan: 1 to add, 0 to change, 0 to destroy.
…
env0_aws_credentials.credentials: Creating...
env0_aws_credentials.credentials: Creation complete after 3s [id=c0babe7c-7ad8-49ca-b837-b4ee7b7b310c]
Apply complete! Resources: 1 added, 0 changed, 0 destroyed.

And that’s it! The provider is initialized and resources are deployed.

Contributing to the OpenTofu Registry

OpenTofu is open-source, meaning that each contribution from the community plays an important role in its growth. 

Here is how you can contribute to the project.

Submitting New Providers and Modules

Adding a new provider or module is a straightforward process. Simply follow these steps:

1. Visit the OpenTofu registry repo and click on README.md and click on Submit new Module or Submit new Provider links.
    
2. Fill in the details, such as the module or provider title, and Github path to the relevant repository, and provide the developer consent by checking the DCO box. 

3. Click on ‘Submit new issue’ to create an entry in the OpenTofu registry.

Keep in mind that the Github repository for the provider and module is public, and the path follows a certain pattern, such as ‘{owner}/terraform-{target}-{name}’ in case of a module.

Submitting New Provider Singing Key

A provider signing key is a unique cryptographic key that is used to sign your provider's packages, as a way for OpenTofu to ensure that the packages remain unchanged and authentic. 

Submitting a GPG key is a simple process:

1. On the OpenTofu registry repo, click on the OpenTofu Provider Key submission page. 

2. Provide relevant information for your submission, such as title, provider namespace, and unique GPG key. 
3. Check the box if the organization membership is public and provide the developer consent by checking the DCO box.
4. When done, click ‘Submit new issue’. 

Join Us!

The new Registry UI streamlines infrastructure management by offering easy access to pre-built providers, modules, and resources, enabling developers to build efficiently and with confidence.

We are grateful to be part of this project's ongoing development and are excited to equip OpenTofu builders with innovative tools and features.

For a look at what's ahead, check out our Roadmap and join the conversation on OpenTofu’s Twitter page, GitHub, and community Slack channel.