Reference a Pulumi stack state from Terraform

main.tf

# Use the external data source to query Pulumi stack state.
# https://www.terraform.io/docs/providers/external/data_source.html
#
# Requires the `pulumi` command-line tool to be installed 
# and a `PULUMI_ACCESS_TOKEN` environment variable when executing Terraform
# in order to authenticate with the Pulumi Console.

variable "pulumi_stack" {
    default = "clstokes/pulumi-cloudtrail-athena/dev"
    # The outputs for this particular stack look like this:
    # {
    #   "accountIdX": "052848974346",
    #   "bucketNameX": "cloudtrail-data-cameronstokes-pulumi",
    #   "databaseName": "cloudtrail_f4dcfba"
    # }
}

data "external" "pulumi" {
      program = ["pulumi", "stack", "output","--json", "--stack", var.pulumi_stack]
}

output "database_name" {
    value = data.external.pulumi.result.databaseName
}

output.log

% terraform apply
data.external.pulumi: Refreshing state...

Apply complete! Resources: 0 added, 0 changed, 0 destroyed.

Outputs:

database_name = cloudtrail_f4dcfba