» Connecting VCS Providers to Terraform Enterprise
Terraform Enterprise (TFE) is more powerful when you integrate it with your version control system (VCS) provider. Although you can use almost all of TFE's features without one, a VCS connection provides major workflow benefits. In particular:
- When workspaces are linked to a VCS repository, TFE can automatically initiate Terraform runs when changes are committed to the specified branch.
- TFE makes code review easier by automatically predicting how pull requests will affect infrastructure.
- Publishing new versions of a private Terraform module is as easy as pushing a tag to the module's repository.
We recommend configuring VCS access when first setting up a TFE organization, and you might need to add additional VCS providers later depending on how your organization grows.
» Supported VCS Providers
TFE supports the following VCS providers:
Use the links above to see details on configuring VCS access for each supported provider. If you use another VCS that is not supported, you can build an integration via the API-driven run workflow.
» How TFE Uses VCS Access
Most workspaces in TFE are associated with a VCS repository, which provides Terraform configurations for that workspace. To find out which repos are available, access their contents, and create webhooks, TFE needs access to your VCS provider.
Although TFE's API lets you create workspaces and push configurations to them without a VCS connection, the primary workflow expects every workspace to be backed by a repository.
To use configurations from VCS, TFE needs to do several things:
- Access a list of repositories, to let you search for repos when creating new workspaces.
- Register webhooks with your VCS provider, to get notified of new commits to a chosen branch.
- Download the contents of a repository at a specific commit in order to run Terraform with that code.
» Webhooks
TFE uses webhooks to monitor new commits and pull requests.
- When someone adds new commits to a branch in a repository linked to TFE, any workspaces based on that branch will begin a Terraform run. Usually a user must inspect the plan output and approve an apply, but you can also enable automatic applies on a per-workspace basis. You can prevent automatic runs by locking a workspace.
- When someone submits a pull request/merge request to a branch from another branch in the same repository, TFE performs a speculative plan with the contents of the request and links to the results on the PR's page. This helps you avoid merging PRs that cause plan failures.
» SSH Keys
For most supported VCS providers, TFE does not need an SSH key — it can do everything it needs with the provider's API and an OAuth token. The exception is Bitbucket Server, which requires an SSH key for downloading repository contents. The setup instructions for Bitbucket Server include this step.
For other VCS providers, most organizations will not need to add an SSH private key. However, if the organization repositories include Git submodules that can only be accessed via SSH, an SSH key can be added along with the OAuth credentials.
If submodules will be cloned via SSH from a private VCS instance, SSH must be running on the standard port 22 on the VCS server.
To add an SSH key to a VCS connection, finish configuring OAuth in the organization settings, and then use the "add a private SSH key" link on the VCS Provider settings page to add a private key that has access to the submodule repositories. When setting up a workspace, if submodules are required, select "Include submodules on clone". More at Workspace settings.
» Multiple VCS Connections
If your infrastructure code is spread across multiple VCS providers, you can configure multiple VCS connections. TFE will ask which VCS connection to use whenever you create a new workspace.
» Configuring VCS Access
TFE uses the OAuth protocol to authenticate with VCS providers.
Important: Even if you've used OAuth before, read the instructions carefully. Since TFE's security model treats each organization as a separate OAuth application, we authenticate with OAuth's developer workflow, which is more complex than the standard user workflow.
The exact steps to authenticate are different for each VCS provider, but they follow this general order:
On your VCS | On TFE |
---|---|
Register your TFE organization as a new app. Get ID and key. | |
Tell TFE how to reach VCS, and provide ID and key. Get callback URL. | |
Provide callback URL. | |
Request VCS access. | |
Approve access request. |
For complete details, click the link for your VCS provider:
Note: Alternately, you can skip the OAuth configuration process and authenticate with a personal access token. This requires using TFE's API. For details, see the OAuth Clients API page.