You can use Upstash terraform provider to create your resources. API key is required in order to create resources.

​
Configure Provider

Provider requires your email address and api key which can be created in console. 
provider "upstash" {
  email = ""
  api_key = ""
}

​
Create Database

As input you need to give database name, region and type. 
resource "upstash_database" "mydb" {
  database_name = "testdblstr"
  region = "eu-west-1"
  type = "free"
}
You can output database credentials as following 
output "endpoint" {
  value = "${upstash_database.mydb.endpoint}"
}

output "port" {
  value = "${upstash_database.mydb.port}"
}
output "password" {
  value = "${upstash_database.mydb.password}"
}
See our Terraform Provider Github Repository for details and examples about Upstash Terraform Provider.