404 error thrown when trying to use the /workspaces/:workspace_id/vars endpoint in Terraform Enterprise

Problem

When trying to use the /workspaces/:workspace_id/vars endpoint, the following error is thrown:

Workspace ID: [ID_VALUE]
###############
This does not work using Workspace ID [ID_VALUE]
{"errors":[{"status":"404","title":"not found"}]}
###############
This does not work using hard coded Workspace [ID_VALUE]
{"errors":[{"status":"404","title":"not found"}]}
###############

Cause

The /workspaces/:workspace_id/vars API endpoint was added in Terraform Enterprise v202001-1.

Solution

The solution to this issue is to upgrade to v202001-1 or later. Alternatively, an environment that is running an earlier version of Terraform Enterprise can use the /vars API endpoint instead.

Additional Information

Further documentation on the /vars endpoint.