feat: Add "num_suffix_format" variable for instance naming

[ryancraig]

Description

• Added num_suffix_format variable. The default value is -%d so use is optional. If the default value is not overridden the module behaves as it did before I made this change.
• Added variable reference to tags and volume_tags in main.tf.
• Added content about this variable to the Inputs section of the README.

Motivation and Context

Some enterprises still maintain policies and naming conventions for resources; they wish to treat resources like pets. For example, I need to adhere to the example naming convention "MyPetEC2Instance01" through "MyPetEC2Instance10" for 10 specified EC2 instances. This change allows such policies to be satisfied if required. This is an optional configuration.

Breaking Changes

No breaking changes. Explicit defaults ensure existing behavior and allow optional use.

How Has This Been Tested?

Manually tested.
example use

module "ec2_instance" {
  # source                 = "terraform-aws-modules/ec2-instance/aws"
  source                 = "git::https://github.com/ryancraig/terraform-aws-ec2-instance.git?ref=develop"
  # version                = "~> 2.0"

  name                                 = var.ec2_instance_name
  use_num_suffix                       = true
  num_suffix_format                    = "%02s"
  instance_count                       = var.ec2_instance_count

  iam_instance_profile                 = var.instance_profile

  ami                                  = var.ami_id
  instance_type                        = var.instance_type
  key_name                             = var.key_name
  monitoring                           = false
  vpc_security_group_ids               = var.security_group_ids
  subnet_id                            = var.subnet_id

  instance_initiated_shutdown_behavior = "stop"
  disable_api_termination              = true

  user_data_base64                     = base64encode(local.user_data)

  tags                                 = merge(var.module_tags, var.common_tags, var.ec2_tags)
}

[bryantbiggs]

hi @ryancraig - thanks for the PR. could you elaborate on what you are trying to solve with this change; what is the use case?

[ryancraig]

@bryantbiggs Some enterprises still maintain policies and naming conventions for resources; they wish to treat resources like pets. For example, I need to adhere to the example naming convention "MyPetEC2Instance01" through "MyPetEC2Instance10" for 10 specified EC2 instances. This change allows such policies to be satisfied if required. This is an optional configuration.

example use

module "ec2_instance" {
  # source                 = "terraform-aws-modules/ec2-instance/aws"
  source                 = "git::https://github.com/ryancraig/terraform-aws-ec2-instance.git?ref=develop"
  # version                = "~> 2.0"

  name                                 = var.ec2_instance_name
  use_num_suffix                       = true
  num_suffix_format                    = "%02s"
  instance_count                       = var.ec2_instance_count

  iam_instance_profile                 = var.instance_profile

  ami                                  = var.ami_id
  instance_type                        = var.instance_type
  key_name                             = var.key_name
  monitoring                           = false
  vpc_security_group_ids               = var.security_group_ids
  subnet_id                            = var.subnet_id

  instance_initiated_shutdown_behavior = "stop"
  disable_api_termination              = true

  user_data_base64                     = base64encode(local.user_data)

  tags                                 = merge(var.module_tags, var.common_tags, var.ec2_tags)
}

[bryantbiggs]

ah ok, yes I have seen this too @ryancraig (unfortunately!). in that case would you mind rebasing/merging master to update your branch and then change the title of your PR to something like feat: add "num_suffix_format" variable for instance naming. this looks ok to me since its backwards compatible

[ryancraig]

@bryantbiggs Yes, I will get these changes made. Thank you!

[ryancraig]

@bryantbiggs I rebased and pushed. Should be good to go. Thanks again!

[ryancraig]

Note that this PR does what PR #86 does but with maximal flexibility as compared to PR #86.

[bryantbiggs]

thanks @ryancraig - I agree; this is the better approach so thank you. @antonbabenko what are your thoughts?

[antonbabenko]

Great! v2.15.0 has been just released, which also fixes #86 .

[github-actions]

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