Improve usage of adb-vnet-injection example (#105)

Changes include:

* Document all input variables for this example
* Allow to specify tags for resources without modifying main code

Author: alexott

examples/adb-vnet-injection/main.tf

@@ -25,16 +25,15 @@ resource "azurerm_resource_group" "this" {
 }
 
 locals {
-  // dltp - databricks labs terraform provider
   prefix   = join("-", [var.workspace_prefix, "${random_string.naming.result}"])
   location = var.rglocation
   dbfsname = join("", [var.dbfs_prefix, "${random_string.naming.result}"]) // dbfs name must not have special chars
 
   // tags that are propagated down to all resources
-  tags = {
+  tags = merge({
     Environment = "Testing"
     Epoch       = random_string.naming.result
-  }
+  }, var.tags)
 }
 
 

examples/adb-vnet-injection/variables.tf

@@ -1,34 +1,49 @@
 variable "no_public_ip" {
-  type    = bool
-  default = true
+  type        = bool
+  default     = true
+  description = "If Secure Cluster Connectivity (No Public IP) should be enabled. Default: true"
 }
 
 variable "rglocation" {
-  type    = string
-  default = "southeastasia"
+  type        = string
+  default     = "southeastasia"
+  description = "Location of resource group to create"
 }
 
 variable "dbfs_prefix" {
-  type    = string
-  default = "dbfs"
+  type        = string
+  default     = "dbfs"
+  description = "Name prefix for DBFS Root Storage account"
 }
 
 variable "node_type" {
-  type    = string
-  default = "Standard_DS3_v2"
+  type        = string
+  default     = "Standard_DS3_v2"
+  description = "Node type for created cluster"
 }
 
 variable "workspace_prefix" {
-  type    = string
-  default = "adb"
+  type        = string
+  default     = "adb"
+  description = "Name prefix for Azure Databricks workspace"
 }
 
 variable "global_auto_termination_minute" {
-  type    = number
-  default = 30
+  type        = number
+  default     = 30
+  description = "Auto-termination time for created cluster"
 }
 
 variable "cidr" {
-  type    = string
-  default = "10.179.0.0/20"
+  type        = string
+  default     = "10.179.0.0/20"
+  description = "Network range for created VNet"
 }
+
+variable "tags" {
+  type        = map(string)
+  description = "Optional tags to add to resources"
+  default     = {}
+}
+
+