Applying varying lifecycle policies to list of s3 buckets - amazon-web-services

Question

I have a list of s3 buckets on which i want to apply different lifecycle policies.
variables.tf
variable "bucket_name" {
type = list(any)
default = ["in", "out", "in-archive", "out-archive"]
}
For the first 2 items in the list I want to have their contents deleted after 180 days. And the remaining 2 buckets to move their contents to GLACIER class and then remove them after 600 days.
I have declared two different resource blocks for varying policies, but the problem is how do I make terraform to start counting index from 3rd element instead of 1st element.
resource block
resource "aws_s3_bucket" "bucket" {
count = length(var.bucket_name)
bucket = "${var.bucket_name[count.index]}"
}
resource "aws_s3_bucket_lifecycle_configuration" "bucket_lifecycle_rule" {
count = length(aws_s3_bucket.bucket)
bucket = aws_s3_bucket.bucket[count.index].id ///Want this index to stop at 2nd element
rule {
status = "Enabled"
id = "bucket-lifecycle-rule"
expiration {
days = 180
}
}
}
resource "aws_s3_bucket_lifecycle_configuration" "archive_bucket_lifecycle_rule" {
count = length(aws_s3_bucket.bucket)
bucket = aws_s3_bucket.bucket[count.index + 4].id ///Want this index to begin from 3rd and end
rule { ///at 4th element
status = "Enabled"
id = "archive-bucket-lifecycle-rule"
transition {
days = 181
storage_class = "GLACIER"
}
expiration {
days = 600
}
}
}
While I approach this rule, i get an error :
in resource "aws_s3_bucket_lifecycle_configuration" "archive_bucket_lifecycle_rule":
31: bucket = aws_s3_bucket.bucket[count.index + 2].id
├────────────────
│ aws_s3_bucket.bucket is tuple with 4 elements
│ count.index is 2
The given key does not identify an element in this collection value.

Answer 1

How about making the input variable a bit more complex to accommodate what you need...
Here is a quick example:
provider "aws" { region = "us-east-1" }
variable "buckets" {
type = map(any)
default = {
"in" : { expiration : 180, transition : 0 },
"out" : { expiration : 120, transition : 0 },
"in-archive" : { expiration : 200, transition : 180 },
"out-archive" : { expiration : 360, transition : 180 }
}
}
resource "aws_s3_bucket" "bucket" {
for_each = var.buckets
bucket = each.key
}
resource "aws_s3_bucket_lifecycle_configuration" "lifecycle" {
for_each = var.buckets
bucket = aws_s3_bucket.bucket[each.key].id
rule {
status = "Enabled"
id = "bucket-lifecycle-rule"
expiration {
days = each.value.expiration
}
}
rule {
status = each.value.transition > 0 ? "Enabled" : "Disabled"
id = "archive-bucket-lifecycle-rule"
transition {
days = each.value.transition
storage_class = "GLACIER"
}
}
}
Now our variable is type = map(any) we can create a more complex object there and pass the lifecycle expiration, you can make that as complex as you need to fit more complex rules