feat: Supports dynamic blocks in regions_config

CHANGELOG.md

@@ -2,7 +2,7 @@
 
 ENHANCEMENTS:
 
-* Supports `dynamic` block for `tags` and `labels`
+* Supports `dynamic` block for `tags`, `labels` and `regions_config`
 
 ## 1.0.0 (Mar 6, 2025)
 

README.md

@@ -57,7 +57,8 @@ Given the different ways of using dynamic blocks, we recommend reviewing the out
 
 #### Dynamic blocks in tags and labels
 
-You can use `dynamic` blocks for `tags` and `labels`. You can also combine the use of dynamic blocks in `tags` and `labels` with individual blocks in the same cluster definition, e.g.:
+You can use `dynamic` blocks for `tags` and `labels`. The plugin assumes that `for_each` has an expression which is evaluated to a `map` of strings.
+You can also combine the use of dynamic blocks in `tags` and `labels` with individual blocks in the same cluster definition, e.g.:
 ```hcl
 tags {
 	key   = "environment"
@@ -72,12 +73,17 @@ dynamic "tags" {
 }
 ```
 
+#### Dynamic blocks in regions_config
+
+You can use `dynamic` blocks for `regions_config`. The plugin assumes that `for_each` has an expression which is evaluated to a `list` or `set` of objects.
+Dynamic block and individual blocks for `regions_config` are not supported at the same time in a `replication_specs`.
+
 ### Limitations
 
 - The plugin doesn't support `regions_config` without `electable_nodes` as there can be some issues with `priority` when they only have `analytics_nodes` and/or `electable_nodes`.
 - [`priority`](https://registry.terraform.io/providers/mongodb/mongodbatlas/latest/docs/resources/cluster#priority-1) is required in `regions_config` and must be a numeric [literal expression](https://developer.hashicorp.com/nomad/docs/job-specification/hcl2/expressions#literal-expressions) between 7 and 1, e.g. `var.priority` is not supported. This is to allow reordering them by descending priority as this is expected in `mongodbatlas_advanced_cluster`.
 - [`num_shards`](https://registry.terraform.io/providers/mongodb/mongodbatlas/latest/docs/resources/cluster#num_shards-2) in `replication_specs` must be a numeric [literal expression](https://developer.hashicorp.com/nomad/docs/job-specification/hcl2/expressions#literal-expressions), e.g. `var.num_shards` is not supported. This is to allow creating a `replication_specs` element per shard in `mongodbatlas_advanced_cluster`.
-- `dynamic` blocks are currently supported only for `tags` and `labels`. **Coming soon**: support for `replication_specs` and `regions_config`.
+- `dynamic` blocks are currently supported only for `tags`, `labels` and `regions_config`. **Coming soon**: support for `replication_specs`.
 
 ## Contributing
 

internal/convert/convert.go

@@ -31,13 +31,13 @@ const (
 	errNumShards   = "setting " + nNumShards
 
 	commentGeneratedBy       = "Generated by atlas-cli-plugin-terraform."
-	commentConfirmReferences = "Please confirm that all references to this resource are updated."
+	commentConfirmReferences = "Please review the changes and confirm that references to this resource are updated."
 	commentMovedBlock        = "Moved blocks"
 	commentRemovedOld        = "Note: Remember to remove or comment out the old cluster definitions."
 )
 
 var (
-	dynamicBlockAllowList = []string{nTags, nLabels}
+	dynamicBlockAllowList = []string{nTags, nLabels, nConfigSrc}
 )
 
 type attrVals struct {
@@ -202,11 +202,11 @@ func fillReplicationSpecs(resourceb *hclwrite.Body, root attrVals) error {
 			break
 		}
 		specbSrc := specSrc.Body()
-		if err := checkDynamicBlock(specbSrc); err != nil {
-			return err
-		}
 		// ok to fail as zone_name is optional
 		_ = hcl.MoveAttr(specbSrc, specb, nZoneName, nZoneName, errRepSpecs)
+		if hasDynamicBlock, err := fillRegionConfigsDynamicBlock(specb, specbSrc, root); err != nil || hasDynamicBlock {
+			return err
+		}
 		shards := specbSrc.GetAttribute(nNumShards)
 		if shards == nil {
 			return fmt.Errorf("%s: %s not found", errRepSpecs, nNumShards)
@@ -306,6 +306,14 @@ func fillBlockOpt(resourceb *hclwrite.Body, name string) {
 	resourceb.SetAttributeRaw(name, hcl.TokensObject(block.Body()))
 }
 
+func fillRegionConfigsDynamicBlock(specb, specbSrc *hclwrite.Body, root attrVals) (bool, error) {
+	d, err := getDynamicBlock(specbSrc, nConfigSrc)
+	if err != nil || d.forEach == nil {
+		return false, err
+	}
+	return true, nil
+}
+
 func fillRegionConfigs(specb, specbSrc *hclwrite.Body, root attrVals) error {
 	var configs []*hclwrite.Body
 	for {

internal/convert/testdata/clu2adv/adv_config_bi_connector_pinned_fcv.out.tf

@@ -32,5 +32,5 @@ resource "mongodbatlas_advanced_cluster" "this" {
   }
 
   # Generated by atlas-cli-plugin-terraform.
-  # Please confirm that all references to this resource are updated.
+  # Please review the changes and confirm that references to this resource are updated.
 }

internal/convert/testdata/clu2adv/analytics_read_only_all_params.out.tf

@@ -36,5 +36,5 @@ resource "mongodbatlas_advanced_cluster" "ar" {
   ]
 
   # Generated by atlas-cli-plugin-terraform.
-  # Please confirm that all references to this resource are updated.
+  # Please review the changes and confirm that references to this resource are updated.
 }

internal/convert/testdata/clu2adv/analytics_read_only_min_params.out.tf

@@ -27,5 +27,5 @@ resource "mongodbatlas_advanced_cluster" "ar" {
   ]
 
   # Generated by atlas-cli-plugin-terraform.
-  # Please confirm that all references to this resource are updated.
+  # Please review the changes and confirm that references to this resource are updated.
 }

internal/convert/testdata/clu2adv/autoscaling.out.tf

@@ -36,5 +36,5 @@ resource "mongodbatlas_advanced_cluster" "autoscaling" {
   ]
 
   # Generated by atlas-cli-plugin-terraform.
-  # Please confirm that all references to this resource are updated.
+  # Please review the changes and confirm that references to this resource are updated.
 }

internal/convert/testdata/clu2adv/data_sources.out.tf

@@ -6,7 +6,7 @@ data "mongodbatlas_advanced_cluster" "singular" {
   use_replication_spec_per_shard = true
 
   # Generated by atlas-cli-plugin-terraform.
-  # Please confirm that all references to this resource are updated.
+  # Please review the changes and confirm that references to this resource are updated.
 }
 
 data "mongodbatlas_advanced_clusters" "plural" {
@@ -15,7 +15,7 @@ data "mongodbatlas_advanced_clusters" "plural" {
   use_replication_spec_per_shard = true
 
   # Generated by atlas-cli-plugin-terraform.
-  # Please confirm that all references to this resource are updated.
+  # Please review the changes and confirm that references to this resource are updated.
 }
 
 data "mongodbatlas_advanced_cluster" "adv_singular" {

internal/convert/testdata/clu2adv/dynamic_regions_config.in.tf

@@ -0,0 +1,49 @@
+resource "mongodbatlas_cluster" "dynamic_regions_config" {
+  project_id                  = var.project_id
+  name                        = "cluster"
+  cluster_type                = "SHARDED"
+  provider_name               = "AWS"
+  provider_instance_size_name = "M10"
+  replication_specs {
+    num_shards = var.replication_specs.num_shards
+    dynamic "regions_config" {
+      for_each = var.replication_specs.regions_config
+      content {
+        region_name     = regions_config.value.region_name
+        electable_nodes = regions_config.value.electable_nodes
+        priority        = regions_config.value.priority
+        read_only_nodes = regions_config.value.read_only_nodes
+      }
+    }
+  }
+}
+
+# example of variable for demostration purposes, not used in the conversion
+variable "replication_specs" {
+  type = object({
+    num_shards = number
+    regions_config = set(object({
+      region_name     = string
+      electable_nodes = number
+      priority        = number
+      read_only_nodes = number
+    }))
+  })
+  default = {
+    num_shards = 3
+    regions_config = [
+      {
+        region_name     = "US_EAST_1"
+        electable_nodes = 3
+        priority        = 7
+        read_only_nodes = 0
+      },
+      {
+        region_name     = "US_WEST_2"
+        electable_nodes = 2
+        priority        = 6
+        read_only_nodes = 1
+      }
+    ]
+  }
+}

internal/convert/testdata/clu2adv/dynamic_regions_config.out.tf

@@ -0,0 +1,59 @@
+resource "mongodbatlas_advanced_cluster" "dynamic_regions_config" {
+  project_id   = var.project_id
+  name         = "cluster"
+  cluster_type = "SHARDED"
+  replication_specs = [
+    for i in range(var.replication_specs.num_shards) : {
+      region_configs = flatten([
+        for priority in range(7, 0, -1) : [
+          for region in var.replication_specs.regions_config : {
+            provider_name = "AWS"
+            region_name   = region.region_name
+            priority      = region.priority
+            electable_specs = region.electable_nodes > 0 ? {
+              node_count    = region.electable_nodes
+              instance_size = "M10"
+            } : null
+            read_only_specs = region.read_only_nodes > 0 ? {
+              node_count    = region.read_only_nodes
+              instance_size = "M10"
+            } : null
+          } if region.priority == priority
+        ]
+      ])
+    }
+  ]
+
+  # Generated by atlas-cli-plugin-terraform.
+  # Please review the changes and confirm that references to this resource are updated.
+}
+
+# example of variable for demostration purposes, not used in the conversion
+variable "replication_specs" {
+  type = object({
+    num_shards = number
+    regions_config = set(object({
+      region_name     = string
+      electable_nodes = number
+      priority        = number
+      read_only_nodes = number
+    }))
+  })
+  default = {
+    num_shards = 3
+    regions_config = [
+      {
+        region_name     = "US_EAST_1"
+        electable_nodes = 3
+        priority        = 7
+        read_only_nodes = 0
+      },
+      {
+        region_name     = "US_WEST_2"
+        electable_nodes = 2
+        priority        = 6
+        read_only_nodes = 1
+      }
+    ]
+  }
+}

internal/convert/testdata/clu2adv/dynamic_tags_labels.out.tf

@@ -20,7 +20,7 @@ resource "mongodbatlas_advanced_cluster" "simplified" {
   tags = var.tags
 
   # Generated by atlas-cli-plugin-terraform.
-  # Please confirm that all references to this resource are updated.
+  # Please review the changes and confirm that references to this resource are updated.
 }
 
 resource "mongodbatlas_advanced_cluster" "expression" {
@@ -47,7 +47,7 @@ resource "mongodbatlas_advanced_cluster" "expression" {
   }
 
   # Generated by atlas-cli-plugin-terraform.
-  # Please confirm that all references to this resource are updated.
+  # Please review the changes and confirm that references to this resource are updated.
 }
 
 resource "mongodbatlas_advanced_cluster" "simplified_individual" {
@@ -78,7 +78,7 @@ resource "mongodbatlas_advanced_cluster" "simplified_individual" {
   )
 
   # Generated by atlas-cli-plugin-terraform.
-  # Please confirm that all references to this resource are updated.
+  # Please review the changes and confirm that references to this resource are updated.
 }
 
 resource "mongodbatlas_advanced_cluster" "expression_individual" {
@@ -111,7 +111,7 @@ resource "mongodbatlas_advanced_cluster" "expression_individual" {
   )
 
   # Generated by atlas-cli-plugin-terraform.
-  # Please confirm that all references to this resource are updated.
+  # Please review the changes and confirm that references to this resource are updated.
 }
 
 resource "mongodbatlas_advanced_cluster" "full_example" {
@@ -157,5 +157,5 @@ resource "mongodbatlas_advanced_cluster" "full_example" {
   )
 
   # Generated by atlas-cli-plugin-terraform.
-  # Please confirm that all references to this resource are updated.
+  # Please review the changes and confirm that references to this resource are updated.
 }

internal/convert/testdata/clu2adv/errors.json

@@ -8,7 +8,6 @@
 	"regions_config_out_of_range_priority": "setting priority: priority is 0 but must be between 1 and 7",
 	"regions_config_non_literal_priority": "setting priority: failed to evaluate number",
 	"replication_specs_unsupported_dynamic": "dynamic blocks are not supported",
-	"regions_config_unsupported_dynamic": "dynamic blocks are not supported",
 	"replication_specs_non_literal_num_shards": "setting num_shards: failed to evaluate number",
 	"replication_specs_missing_num_shards": "num_shards not found"
 }

internal/convert/testdata/clu2adv/free_cluster_with_count.out.tf

@@ -26,5 +26,5 @@ resource "mongodbatlas_advanced_cluster" "free_cluster" { # comment in the resou
   ]
 
   # Generated by atlas-cli-plugin-terraform.
-  # Please confirm that all references to this resource are updated.
+  # Please review the changes and confirm that references to this resource are updated.
 }

internal/convert/testdata/clu2adv/includeMoved_multiple.out.tf

@@ -19,7 +19,7 @@ resource "mongodbatlas_advanced_cluster" "cluster1" {
   ]
 
   # Generated by atlas-cli-plugin-terraform.
-  # Please confirm that all references to this resource are updated.
+  # Please review the changes and confirm that references to this resource are updated.
 }
 
 resource "mongodbatlas_advanced_cluster" "cluster2" {
@@ -43,7 +43,7 @@ resource "mongodbatlas_advanced_cluster" "cluster2" {
   ]
 
   # Generated by atlas-cli-plugin-terraform.
-  # Please confirm that all references to this resource are updated.
+  # Please review the changes and confirm that references to this resource are updated.
 }
 
 resource "mongodbatlas_advanced_cluster" "count" {
@@ -69,7 +69,7 @@ resource "mongodbatlas_advanced_cluster" "count" {
   ]
 
   # Generated by atlas-cli-plugin-terraform.
-  # Please confirm that all references to this resource are updated.
+  # Please review the changes and confirm that references to this resource are updated.
 }
 
 resource "mongodbatlas_advanced_cluster" "forEach" {
@@ -95,7 +95,7 @@ resource "mongodbatlas_advanced_cluster" "forEach" {
   ]
 
   # Generated by atlas-cli-plugin-terraform.
-  # Please confirm that all references to this resource are updated.
+  # Please review the changes and confirm that references to this resource are updated.
 }
 
 resource "another_resource" "another" {

internal/convert/testdata/clu2adv/includeMoved_single.out.tf

@@ -19,7 +19,7 @@ resource "mongodbatlas_advanced_cluster" "cluster" {
   ]
 
   # Generated by atlas-cli-plugin-terraform.
-  # Please confirm that all references to this resource are updated.
+  # Please review the changes and confirm that references to this resource are updated.
 }
 
 # Moved blocks

internal/convert/testdata/clu2adv/multi_region.out.tf

@@ -43,5 +43,5 @@ resource "mongodbatlas_advanced_cluster" "multi_region" {
   ]
 
   # Generated by atlas-cli-plugin-terraform.
-  # Please confirm that all references to this resource are updated.
+  # Please review the changes and confirm that references to this resource are updated.
 }

internal/convert/testdata/clu2adv/multi_replicaction_specs.out.tf

@@ -37,7 +37,7 @@ resource "mongodbatlas_advanced_cluster" "multirep" {
   ]
 
   # Generated by atlas-cli-plugin-terraform.
-  # Please confirm that all references to this resource are updated.
+  # Please review the changes and confirm that references to this resource are updated.
 }
 
 resource "mongodbatlas_advanced_cluster" "geo" {
@@ -124,5 +124,5 @@ resource "mongodbatlas_advanced_cluster" "geo" {
   ]
 
   # Generated by atlas-cli-plugin-terraform.
-  # Please confirm that all references to this resource are updated.
+  # Please review the changes and confirm that references to this resource are updated.
 }