Terraform Simple Registry

This repository contains simple implementations of the Terraform registry protocols.

This package is designed with the principle of "small pieces loosely joined": it deals only with the Terraform protocols and expects other concerns to be dealt with via complementary software. For example:

• Each of the registry services is provided as a separate program, allowing the user to decide which to use and how to deploy them.

• Authentication is not directly integrated, but can be applied by e.g. putting nginx in front of this program's server and configuring it to verify JSON Web Tokens, or similar.

• These programs provide read-only access to data available in the local filesystem. This data can either be placed manually or updated automatically by separate software in response to hooks from a remote Git repository, etc.

• A simple, static configuration system is used, so these files can either be hand-edited or generated automatically by some other external program.

Delegating all but the core concerns to other software gives users the flexibility to customize their deployment and integrate these programs with other systems and processes.

This program is not a HashiCorp product and is not directly supported by the Terraform team at HashiCorp.

An "out-of-the-box" private registry solution, with support from HashiCorp, is available as part of Terraform Enterprise. This implementation integrates well with other Terraform Enterprise features.

Included Servers

The design of this codebase is to have a separate server program for each of the separate Terraform native service protocols it supports. The protocols currently supported are:

• Module registry v1 (modules.v1)

Service Discovery

Terraform uses a simple service discovery protocol to locate remote services when given a "friendly hostname" by the user. For example, the hostname at the start of a module source string like example.com/foo/bar/baz is such a hostname, causing Terraform to attempt service discovery on that host.

The programs in this package each expose functionality for one of Terraform's supported services. It's your responsibility as the deployer to place a service discovery document on some suitable hostname to allow Terraform to find the services you've deployed. It is not required that the servers themselves be deployed at the same hostname.

Terraform looks for a discovery document by accessing the given hostname with HTTPS and requesting the path /.well-known/terraform.json, at which it expects to find an application/json response with content like the following:

{
  "modules.v1": "http://modules.example.com/v1/"
}

Each key in this object relates to a single service, which in turn maps to one server program in this repository. The documentation for each of the included servers (linked above) defines which service discovery key it relates to.