How to convert list to map in terraform? - terraform

Question

string vals=var.vals // which will contain string in the format below
//"hr:recruitment,department:human,tool:sap,fruit:apple"
labels={
hostname=var.hostname
monitored=var.monitored
customer=var.cust1
machine-type=var.machinetype
}
I need to set labels(key,value) pairs for google_compute_instance by combining the above 2 properties to form a map.
So i converted vals to list by this code split(",",var.vals)
This gives me a list
tolist([
"hr:recruitment",
"department:human",
"tool:sap",
"fruit:apple",
])
Expected Output consisting of only map(string) combining labels and vals
labels:
{
hostname:var.hostname
monitored:var.monitored
customer:var.cust1
machine-type:var.machinetype
hr:"recruitment",
department:"human",
tool:"sap",
fruit:"apple"
}
How to convert this list to a map and combine it with labels?

Answer 1

I tried below & it seems to be working but it heavily relies on data quality of vals string (shouldn't contain duplicate keys). At it's core it relies on zipmap to build the map from keys & values lists.
// Having vals as a string variable
variable "vals" {
description = "The name of availability set"
type = string
default = "hr:recruitment,department:human,tool:sap,fruit:apple"
}
// hostname, monitored, cust1 & machinetype vars
variable "hostname" {
type = string
default = "dummy.net"
}
variable "monitored" {
type = bool
default = true
}
variable "cust1" {
type = string
default = "xyz"
}
variable "machinetype" {
type = string
default = "linux"
}
locals {
// parsing locally to split the vals string to fetch the keys
keys = [
for s in split(",", var.vals) : split(":", s)[0]
]
// parsing locally to split the vals string to fetch the values
values = [
for s in split(",", var.vals) : split(":", s)[1]
]
//I used labels also as vars
labels = {
hostname = var.hostname
monitored = var.monitored
customer = var.cust1
machine-type = var.machinetype
}
}
// Finally, zipmap to construct map from keys & values & merge with local.labels
output "final_map" {
value = merge(local.labels, zipmap(local.keys, local.values))
}
Finally, the output looks like below ::
Apply complete! Resources: 0 added, 0 changed, 0 destroyed.
Outputs:
final_map = {
"customer" = "xyz"
"department" = "human"
"fruit" = "apple"
"hostname" = "dummy.net"
"hr" = "recruitment"
"machine-type" = "linux"
"monitored" = true
"tool" = "sap"
}