A table can have more than one column family.

This commit fixes GoogleCloudPlatform#1064 by allowing to add more than one column family. Split
keys are also now optional, and there is no possibility to set defaults for all
tables (since keys and column families are related to the data and schema for
each table, it is difficult that several tables share the same values).

Also, declaring a table with no split keys nor column families requires
initializing the table to an empty map, instead of using null.

modules/bigtable-instance/README.md

@@ -22,10 +22,9 @@ module "bigtable-instance" {
   cluster_id = "instance"
   zone       = "europe-west1-b"
   tables = {
-    test1 = null,
+    test1 = {},
     test2 = {
       split_keys    = ["a", "b", "c"]
-      column_family = null
     }
   }
   iam = {
@@ -35,6 +34,30 @@ module "bigtable-instance" {
 # tftest modules=1 resources=4
 ```
 
+### Instance with tables and column families
+
+```hcl
+
+module "bigtable-instance" {
+  source     = "./fabric/modules/bigtable-instance"
+  project_id = "my-project"
+  name       = "instance"
+  cluster_id = "instance"
+  zone       = "europe-west1-b"
+  tables = {
+    test1 = {},
+    test2 = {
+      split_keys     = ["a", "b", "c"]
+      column_families = ["cf1", "cf2", "cf3"]
+    }
+    test3 = {
+      column_families = ["cf1"]
+    }
+  }
+}
+# tftest modules=1 resources=4
+```
+
 ### Instance with static number of nodes
 
 If you are not using autoscaling settings, you must set a specific number of nodes with the variable `num_nodes`.
@@ -101,7 +124,7 @@ module "bigtable-instance" {
 |---|---|:---:|:---:|:---:|
 | [name](variables.tf#L56) | The name of the Cloud Bigtable instance. | <code>string</code> | ✓ |  |
 | [project_id](variables.tf#L67) | Id of the project where datasets will be created. | <code>string</code> | ✓ |  |
-| [zone](variables.tf#L99) | The zone to create the Cloud Bigtable cluster in. | <code>string</code> | ✓ |  |
+| [zone](variables.tf#L87) | The zone to create the Cloud Bigtable cluster in. | <code>string</code> | ✓ |  |
 | [autoscaling_config](variables.tf#L17) | Settings for autoscaling of the instance. If you set this variable, the variable num_nodes is ignored. | <code title="object&#40;&#123;&#10;  min_nodes      &#61; number&#10;  max_nodes      &#61; number&#10;  cpu_target     &#61; number,&#10;  storage_target &#61; optional&#40;number, null&#41;&#10;&#125;&#41;">object&#40;&#123;&#8230;&#125;&#41;</code> |  | <code>null</code> |
 | [cluster_id](variables.tf#L28) | The ID of the Cloud Bigtable cluster. | <code>string</code> |  | <code>&#34;europe-west1&#34;</code> |
 | [deletion_protection](variables.tf#L34) | Whether or not to allow Terraform to destroy the instance. Unless this field is set to false in Terraform state, a terraform destroy or terraform apply that would delete the instance will fail. | <code></code> |  | <code>true</code> |
@@ -110,8 +133,7 @@ module "bigtable-instance" {
 | [instance_type](variables.tf#L50) | (deprecated) The instance type to create. One of 'DEVELOPMENT' or 'PRODUCTION'. | <code>string</code> |  | <code>null</code> |
 | [num_nodes](variables.tf#L61) | The number of nodes in your Cloud Bigtable cluster. This value is ignored if you are using autoscaling. | <code>number</code> |  | <code>1</code> |
 | [storage_type](variables.tf#L72) | The storage type to use. | <code>string</code> |  | <code>&#34;SSD&#34;</code> |
-| [table_options_defaults](variables.tf#L78) | Default option of tables created in the BigTable instance. | <code title="object&#40;&#123;&#10;  split_keys    &#61; list&#40;string&#41;&#10;  column_family &#61; string&#10;&#125;&#41;">object&#40;&#123;&#8230;&#125;&#41;</code> |  | <code title="&#123;&#10;  split_keys    &#61; &#91;&#93;&#10;  column_family &#61; null&#10;&#125;">&#123;&#8230;&#125;</code> |
-| [tables](variables.tf#L90) | Tables to be created in the BigTable instance, options can be null. | <code title="map&#40;object&#40;&#123;&#10;  split_keys    &#61; list&#40;string&#41;&#10;  column_family &#61; string&#10;&#125;&#41;&#41;">map&#40;object&#40;&#123;&#8230;&#125;&#41;&#41;</code> |  | <code>&#123;&#125;</code> |
+| [tables](variables.tf#L78) | Tables to be created in the BigTable instance, options can be null or ignored. | <code title="map&#40;object&#40;&#123;&#10;  split_keys    &#61; optional&#40;list&#40;string&#41;&#41;&#10;  column_families &#61; optional&#40;list&#40;string&#41;&#41;&#10;&#125;&#41;&#41;">map&#40;object&#40;&#123;&#8230;&#125;&#41;&#41;</code> |  | <code>&#123;&#125;</code> |
 
 ## Outputs
 

modules/bigtable-instance/main.tf

@@ -15,9 +15,6 @@
  */
 
 locals {
-  tables = {
-    for k, v in var.tables : k => v != null ? v : var.table_options_defaults
-  }
   num_nodes = var.autoscaling_config == null ? var.num_nodes : null
 }
 
@@ -54,17 +51,17 @@ resource "google_bigtable_instance_iam_binding" "default" {
 }
 
 resource "google_bigtable_table" "default" {
-  for_each      = local.tables
+  for_each      = var.tables
   project       = var.project_id
   instance_name = google_bigtable_instance.default.name
   name          = each.key
   split_keys    = each.value.split_keys
 
   dynamic "column_family" {
-    for_each = each.value.column_family != null ? [""] : []
+    for_each = each.value.column_families
 
     content {
-      family = each.value.column_family
+      family = column_family.value
     }
   }
 }

modules/bigtable-instance/variables.tf

@@ -75,25 +75,12 @@ variable "storage_type" {
   default     = "SSD"
 }
 
-variable "table_options_defaults" {
-  description = "Default option of tables created in the BigTable instance."
-  type = object({
-    split_keys    = list(string)
-    column_family = string
-  })
-  default = {
-    split_keys    = []
-    column_family = null
-  }
-}
-
 variable "tables" {
-  description = "Tables to be created in the BigTable instance, options can be null."
+  description = "Tables to be created in the BigTable instance."
   type = map(object({
-    split_keys    = list(string)
-    column_family = string
+    split_keys    = optional(list(string), [])
+    column_families = optional(list(string), [])
   }))
-  default = {}
 }
 
 variable "zone" {