Implement Local Secondary Index Support (#21)

* updated to use local secondary indexes

* updated gsi comment to lsi

* ran fmt

* updated LSI null resource name

* updated GSI null resource name

* fixed another timstamp in readme, and made sure md and yaml are in sync.

Author: jamisonhyatt

README.md

@@ -81,6 +81,21 @@ module "dynamodb_table" {
     },
   ]
 
+  local_secondary_index_map = [
+    {
+      name      = "TimestampSortIndex"
+      range_key = "Timestamp"
+      projection_type    = "INCLUDE"
+      non_key_attributes = ["HashKey", "RangeKey"]
+    },
+    {
+      name      = "HighWaterIndex"
+      range_key = "Timestamp"
+      projection_type    = "INCLUDE"
+      non_key_attributes = ["HashKey", "RangeKey"]
+    }
+  ]
+
   global_secondary_index_map = [
     {
       name               = "DailyAverageIndex"
@@ -135,6 +150,7 @@ Available targets:
 | enable_encryption | Enable DynamoDB server-side encryption | string | `true` | no |
 | enable_point_in_time_recovery | Enable DynamoDB point in time recovery | string | `true` | no |
 | enable_streams | Enable DynamoDB streams | string | `false` | no |
+| local_secondary_index_map | Additional local secondary indexes in the form of a list of mapped values | list | `<list>` | no |
 | global_secondary_index_map | Additional global secondary indexes in the form of a list of mapped values | list | `<list>` | no |
 | hash_key | DynamoDB table Hash Key | string | - | yes |
 | name | Name  (e.g. `app` or `cluster`) | string | - | yes |

README.yaml

@@ -112,6 +112,21 @@ usage: |-
       },
     ]
 
+    local_secondary_index_map = [
+    {
+      name      = "TimestampSortIndex"
+      range_key = "Timestamp"
+      projection_type    = "INCLUDE"
+      non_key_attributes = ["HashKey", "RangeKey"]
+    },
+    {
+      name      = "HighWaterIndex"
+      range_key = "Timestamp"
+      projection_type    = "INCLUDE"
+      non_key_attributes = ["HashKey", "RangeKey"]
+    }
+  ]
+
     global_secondary_index_map = [
       {
         name               = "DailyAverageIndex"

docs/terraform.md

@@ -16,6 +16,7 @@
 | enable_encryption | Enable DynamoDB server-side encryption | string | `true` | no |
 | enable_point_in_time_recovery | Enable DynamoDB point in time recovery | string | `true` | no |
 | enable_streams | Enable DynamoDB streams | string | `false` | no |
+| local_secondary_index_map | local secondary indexes in the form of a list of mapped values | list | `<list>` | no |
 | global_secondary_index_map | Additional global secondary indexes in the form of a list of mapped values | list | `<list>` | no |
 | hash_key | DynamoDB table Hash Key | string | - | yes |
 | name | Name  (e.g. `app` or `cluster`) | string | - | yes |
@@ -30,6 +31,7 @@
 
 | Name | Description |
 |------|-------------|
+| local_secondary_index_names | DynamoDB local index names |
 | global_secondary_index_names | DynamoDB secondary index names |
 | table_arn | DynamoDB table ARN |
 | table_id | DynamoDB table ID |

examples/complete/main.tf

@@ -22,6 +22,25 @@ module "dynamodb_table" {
       name = "HighWater"
       type = "N"
     },
+    {
+      name = "Timestamp"
+      type = "S"
+    },
+  ]
+
+  local_secondary_index_map = [
+    {
+      name               = "TimestampSortIndex"
+      range_key          = "Timestamp"
+      projection_type    = "INCLUDE"
+      non_key_attributes = ["HashKey", "RangeKey"]
+    },
+    {
+      name               = "HighWaterIndex"
+      range_key          = "Timestamp"
+      projection_type    = "INCLUDE"
+      non_key_attributes = ["HashKey", "RangeKey"]
+    },
   ]
 
   global_secondary_index_map = [

main.tf

@@ -28,7 +28,7 @@ locals {
   attributes_final = "${slice(local.attributes, local.from_index, length(local.attributes))}"
 }
 
-resource "null_resource" "global_secondary_indexe_names" {
+resource "null_resource" "global_secondary_index_names" {
   count = "${length(var.global_secondary_index_map)}"
 
   # Convert the multi-item `global_secondary_index_map` into a simple `map` with just one item `name` since `triggers` does not support `lists` in `maps` (which are used in `non_key_attributes`)
@@ -37,6 +37,15 @@ resource "null_resource" "global_secondary_indexe_names" {
   triggers = "${map("name", lookup(var.global_secondary_index_map[count.index], "name"))}"
 }
 
+resource "null_resource" "local_secondary_index_names" {
+  count = "${length(var.local_secondary_index_map)}"
+
+  # Convert the multi-item `local_secondary_index_map` into a simple `map` with just one item `name` since `triggers` does not support `lists` in `maps` (which are used in `non_key_attributes`)
+  # See `examples/complete`
+  # https://www.terraform.io/docs/providers/aws/r/dynamodb_table.html#non_key_attributes-1
+  triggers = "${map("name", lookup(var.local_secondary_index_map[count.index], "name"))}"
+}
+
 resource "aws_dynamodb_table" "default" {
   name             = "${module.dynamodb_label.id}"
   read_capacity    = "${var.autoscale_min_read_capacity}"
@@ -60,6 +69,7 @@ resource "aws_dynamodb_table" "default" {
 
   attribute              = ["${local.attributes_final}"]
   global_secondary_index = ["${var.global_secondary_index_map}"]
+  local_secondary_index  = ["${var.local_secondary_index_map}"]
 
   ttl {
     attribute_name = "${var.ttl_attribute}"
@@ -79,7 +89,7 @@ module "dynamodb_autoscaler" {
   attributes                   = "${var.attributes}"
   dynamodb_table_name          = "${aws_dynamodb_table.default.id}"
   dynamodb_table_arn           = "${aws_dynamodb_table.default.arn}"
-  dynamodb_indexes             = ["${null_resource.global_secondary_indexe_names.*.triggers.name}"]
+  dynamodb_indexes             = ["${null_resource.global_secondary_index_names.*.triggers.name}"]
   autoscale_write_target       = "${var.autoscale_write_target}"
   autoscale_read_target        = "${var.autoscale_read_target}"
   autoscale_min_read_capacity  = "${var.autoscale_min_read_capacity}"

outputs.tf

@@ -14,10 +14,15 @@ output "table_arn" {
 }
 
 output "global_secondary_index_names" {
-  value       = ["${null_resource.global_secondary_indexe_names.*.triggers.name}"]
+  value       = ["${null_resource.global_secondary_index_names.*.triggers.name}"]
   description = "DynamoDB secondary index names"
 }
 
+output "local_secondary_index_names" {
+  value       = ["${null_resource.local_secondary_index_names.*.triggers.name}"]
+  description = "DynamoDB local index names"
+}
+
 output "table_stream_arn" {
   value       = "${aws_dynamodb_table.default.stream_arn}"
   description = "DynamoDB table stream ARN"

variables.tf

@@ -119,3 +119,9 @@ variable "global_secondary_index_map" {
   default     = []
   description = "Additional global secondary indexes in the form of a list of mapped values"
 }
+
+variable "local_secondary_index_map" {
+  type        = "list"
+  default     = []
+  description = "Additional local secondary indexes in the form of a list of mapped values"
+}