This terraform module is used as a default, standard, load balanced environment suitable for initial production rails deploys. It has a lot of configuration but it also fairly opinionated.
The load balancer is tricky. If you have access to the DNS zone on AWS/Route53, it can be provisioned automatically (if we write this feature):
route53_zone_id = "Z0123456789ABCDEF0"
lb_domain_name = "my.production.site"
lb_alternate_names = ["www.production.site", "production.site"]
If not, e.g. if you have to do email or outside DNS validation, you can instead maunally create a cert on AWS and then specify the ARN:
lb_certificate_arn "aws.arn.whateverexamplethign"
If you do not specify either lb_domain_name or lb_certificate_arn your load balancer will not be created with an HTTPS/TLS target group, it will be HTTP only.
Most rails projects need a redis for things like sidekiq, actioncable, etc, so this tf script can create an elasticache redis instance/cluster for you. Alternatively, you can configure a worker server to run redis, but using elasticache is is usually preferred.
# Number of redis nodes in the cluster.
redis_node_count = 1
redis_node_type = "cache.t4g.micro"
redis_engine_version = "6.x"
redis_parameter_group_name = "default.redis6.x"
By default, this will not create a redis cluster.