Support transitions to/from dedicated masters by setting hot tier nod…

…e_roles to unknown on topology size changes (#682)

ec/acc/deployment_dedicated_test.go

@@ -69,17 +69,39 @@ func TestAccDeployment_dedicated_coordinating(t *testing.T) {
 func TestAccDeployment_dedicated_master(t *testing.T) {
 	resName := "ec_deployment.dedicated_master"
 	randomName := prefix + acctest.RandStringFromCharSet(10, acctest.CharSetAlphaNum)
-	startCfg := "testdata/deployment_dedicated_master.tf"
-	cfg := fixtureAccDeploymentResourceBasicDefaults(t, startCfg, randomName, getRegion(), hotWarmTemplate)
+	belowCfg := "testdata/deployment_dedicated_master_below_threshold.tf"
+	aboveCfg := "testdata/deployment_dedicated_master_above_threshold.tf"
+	belowThresholdCfg := fixtureAccDeploymentResourceBasicDefaults(t, belowCfg, randomName, getRegion(), defaultTemplate)
+	aboveThresholdCfg := fixtureAccDeploymentResourceBasicDefaults(t, aboveCfg, randomName, getRegion(), defaultTemplate)
 
 	resource.ParallelTest(t, resource.TestCase{
 		PreCheck:                 func() { testAccPreCheck(t) },
 		ProtoV6ProviderFactories: testAccProviderFactory,
 		CheckDestroy:             testAccDeploymentDestroy,
 		Steps: []resource.TestStep{
 			{
-				// Create a deployment with dedicated master nodes.
-				Config: cfg,
+				// Create a deployment below the dedicate master threshold.
+				Config: belowThresholdCfg,
+				Check: resource.ComposeAggregateTestCheckFunc(
+					resource.TestCheckResourceAttrSet(resName, "elasticsearch.hot.instance_configuration_id"),
+
+					resource.TestCheckNoResourceAttr(resName, "elasticsearch.cold"),
+					resource.TestCheckNoResourceAttr(resName, "elasticsearch.master"),
+					resource.TestCheckNoResourceAttr(resName, "elasticsearch.warm"),
+
+					resource.TestCheckResourceAttr(resName, "elasticsearch.hot.size", "1g"),
+					resource.TestCheckResourceAttr(resName, "elasticsearch.hot.size_resource", "memory"),
+					resource.TestCheckResourceAttrSet(resName, "elasticsearch.hot.node_roles.#"),
+					resource.TestCheckResourceAttr(resName, "elasticsearch.hot.zone_count", "3"),
+
+					resource.TestCheckNoResourceAttr(resName, "kibana"),
+					resource.TestCheckNoResourceAttr(resName, "apm"),
+					resource.TestCheckNoResourceAttr(resName, "enterprise_search"),
+				),
+			},
+			{
+				// Expand the deployment above the dedicated master threshold.
+				Config: aboveThresholdCfg,
 				Check: resource.ComposeAggregateTestCheckFunc(
 					resource.TestCheckResourceAttrSet(resName, "elasticsearch.cold.instance_configuration_id"),
 					resource.TestCheckResourceAttrSet(resName, "elasticsearch.hot.instance_configuration_id"),
@@ -106,6 +128,26 @@ func TestAccDeployment_dedicated_master(t *testing.T) {
 					resource.TestCheckResourceAttrSet(resName, "elasticsearch.warm.node_roles.#"),
 					resource.TestCheckResourceAttr(resName, "elasticsearch.warm.zone_count", "2"),
 
+					resource.TestCheckNoResourceAttr(resName, "kibana"),
+					resource.TestCheckNoResourceAttr(resName, "apm"),
+					resource.TestCheckNoResourceAttr(resName, "enterprise_search"),
+				),
+			},
+			{
+				// Shrink it back below the threshold.
+				Config: belowThresholdCfg,
+				Check: resource.ComposeAggregateTestCheckFunc(
+					resource.TestCheckResourceAttrSet(resName, "elasticsearch.hot.instance_configuration_id"),
+
+					resource.TestCheckNoResourceAttr(resName, "elasticsearch.cold"),
+					resource.TestCheckNoResourceAttr(resName, "elasticsearch.master"),
+					resource.TestCheckNoResourceAttr(resName, "elasticsearch.warm"),
+
+					resource.TestCheckResourceAttr(resName, "elasticsearch.hot.size", "1g"),
+					resource.TestCheckResourceAttr(resName, "elasticsearch.hot.size_resource", "memory"),
+					resource.TestCheckResourceAttrSet(resName, "elasticsearch.hot.node_roles.#"),
+					resource.TestCheckResourceAttr(resName, "elasticsearch.hot.zone_count", "3"),
+
 					resource.TestCheckNoResourceAttr(resName, "kibana"),
 					resource.TestCheckNoResourceAttr(resName, "apm"),
 					resource.TestCheckNoResourceAttr(resName, "enterprise_search"),

ec/acc/testdata/deployment_dedicated_master_below_threshold.tf

@@ -0,0 +1,19 @@
+data "ec_stack" "latest" {
+  version_regex = "latest"
+  region        = "%s"
+}
+
+resource "ec_deployment" "dedicated_master" {
+  name                   = "%s"
+  region                 = "%s"
+  version                = data.ec_stack.latest.version
+  deployment_template_id = "%s"
+
+  elasticsearch = {
+    hot = {
+      zone_count  = 3
+      size        = "1g"
+      autoscaling = {}
+    }
+  }
+}

ec/ecresource/deploymentresource/elasticsearch/v2/node_roles_plan_modifier.go

@@ -20,6 +20,10 @@ package v2
 import (
 	"context"
 
+	"github.com/hashicorp/terraform-plugin-framework/types"
+
+	"github.com/elastic/terraform-provider-ec/ec/internal/planmodifiers"
+	"github.com/hashicorp/terraform-plugin-framework/path"
 	"github.com/hashicorp/terraform-plugin-framework/resource/schema/planmodifier"
 )
 
@@ -70,3 +74,41 @@ func (r nodeRolesDefault) Description(ctx context.Context) string {
 func (r nodeRolesDefault) MarkdownDescription(ctx context.Context) string {
 	return "Use current state if it's still valid."
 }
+
+type setUnknownOnTopologyChanges struct{}
+
+var (
+	tierNames        = []string{"hot", "coordinating", "master", "warm", "cold", "frozen"}
+	sizingAttributes = []string{"size", "zone_count"}
+)
+
+func (m setUnknownOnTopologyChanges) PlanModifySet(ctx context.Context, req planmodifier.SetRequest, resp *planmodifier.SetResponse) {
+	if req.PlanValue.IsUnknown() || req.PlanValue.IsNull() {
+		return
+	}
+
+	for _, tierName := range tierNames {
+		for _, attr := range sizingAttributes {
+			hasChanged, diags := planmodifiers.AttributeChanged(ctx, path.Root("elasticsearch").AtName(tierName).AtName(attr), req.Plan, req.State)
+			resp.Diagnostics.Append(diags...)
+			if resp.Diagnostics.HasError() {
+				return
+			}
+
+			if hasChanged {
+				resp.PlanValue = types.SetUnknown(types.StringType)
+				return
+			}
+		}
+	}
+}
+
+// Description returns a human-readable description of the plan modifier.
+func (r setUnknownOnTopologyChanges) Description(ctx context.Context) string {
+	return "Sets the plan value to unknown if the size of any topology element has changed."
+}
+
+// MarkdownDescription returns a markdown description of the plan modifier.
+func (r setUnknownOnTopologyChanges) MarkdownDescription(ctx context.Context) string {
+	return "Sets the plan value to unknown if the size of any topology element has changed."
+}

ec/ecresource/deploymentresource/elasticsearch/v2/schema.go

@@ -18,6 +18,7 @@
 package v2
 
 import (
+	"fmt"
 	"strings"
 
 	"github.com/elastic/terraform-provider-ec/ec/internal/planmodifiers"
@@ -94,13 +95,29 @@ func ElasticsearchSchema() schema.Attribute {
 				Computed:    true,
 			},
 
-			"hot":          elasticsearchTopologySchema("'hot' topology element", true, "hot"),
-			"coordinating": elasticsearchTopologySchema("'coordinating' topology element", false, "coordinating"),
-			"master":       elasticsearchTopologySchema("'master' topology element", false, "master"),
-			"warm":         elasticsearchTopologySchema("'warm' topology element", false, "warm"),
-			"cold":         elasticsearchTopologySchema("'cold' topology element", false, "cold"),
-			"frozen":       elasticsearchTopologySchema("'frozen' topology element", false, "frozen"),
-			"ml":           elasticsearchTopologySchema("'ml' topology element", false, "ml"),
+			"hot": elasticsearchTopologySchema(topologySchemaOptions{
+				tierName:                      "hot",
+				required:                      true,
+				nodeRolesImpactedBySizeChange: true,
+			}),
+			"coordinating": elasticsearchTopologySchema(topologySchemaOptions{
+				tierName: "coordinating",
+			}),
+			"master": elasticsearchTopologySchema(topologySchemaOptions{
+				tierName: "master",
+			}),
+			"warm": elasticsearchTopologySchema(topologySchemaOptions{
+				tierName: "warm",
+			}),
+			"cold": elasticsearchTopologySchema(topologySchemaOptions{
+				tierName: "cold",
+			}),
+			"frozen": elasticsearchTopologySchema(topologySchemaOptions{
+				tierName: "frozen",
+			}),
+			"ml": elasticsearchTopologySchema(topologySchemaOptions{
+				tierName: "ml",
+			}),
 
 			"trust_account": elasticsearchTrustAccountSchema(),
 
@@ -402,27 +419,41 @@ func elasticsearchTrustExternalSchema() schema.Attribute {
 	}
 }
 
-func elasticsearchTopologySchema(description string, required bool, topologyAttributeName string) schema.Attribute {
+type topologySchemaOptions struct {
+	required                      bool
+	nodeRolesImpactedBySizeChange bool
+	tierName                      string
+}
+
+func elasticsearchTopologySchema(options topologySchemaOptions) schema.Attribute {
+	nodeRolesPlanModifiers := []planmodifier.Set{
+		UseNodeRolesDefault(),
+	}
+
+	if options.nodeRolesImpactedBySizeChange {
+		nodeRolesPlanModifiers = append(nodeRolesPlanModifiers, setUnknownOnTopologyChanges{})
+	}
+
 	return schema.SingleNestedAttribute{
-		Optional: !required,
+		Optional: !options.required,
 		// it should be Computed but Computed triggers TF weird behaviour that leads to unempty plan for zero change config
 		// Computed:    true,
-		Required:    required,
-		Description: description,
+		Required:    options.required,
+		Description: fmt.Sprintf("'%s' topology element", options.tierName),
 		Attributes: map[string]schema.Attribute{
 			"instance_configuration_id": schema.StringAttribute{
 				Description: `Computed Instance Configuration ID of the topology element`,
 				Computed:    true,
 				PlanModifiers: []planmodifier.String{
-					UseTopologyStateForUnknown(topologyAttributeName),
+					UseTopologyStateForUnknown(options.tierName),
 				},
 			},
 			"size": schema.StringAttribute{
 				Description: `Amount of "size_resource" per node in the "<size in GB>g" notation`,
 				Computed:    true,
 				Optional:    true,
 				PlanModifiers: []planmodifier.String{
-					UseTopologyStateForUnknown(topologyAttributeName),
+					UseTopologyStateForUnknown(options.tierName),
 				},
 			},
 			"size_resource": schema.StringAttribute{
@@ -438,7 +469,7 @@ func elasticsearchTopologySchema(description string, required bool, topologyAttr
 				Computed:    true,
 				Optional:    true,
 				PlanModifiers: []planmodifier.Int64{
-					UseTopologyStateForUnknown(topologyAttributeName),
+					UseTopologyStateForUnknown(options.tierName),
 				},
 			},
 			"node_type_data": schema.StringAttribute{
@@ -474,14 +505,12 @@ func elasticsearchTopologySchema(description string, required bool, topologyAttr
 				},
 			},
 			"node_roles": schema.SetAttribute{
-				ElementType: types.StringType,
-				Description: `The computed list of node roles for the current topology element`,
-				Computed:    true,
-				PlanModifiers: []planmodifier.Set{
-					UseNodeRolesDefault(),
-				},
+				ElementType:   types.StringType,
+				Description:   `The computed list of node roles for the current topology element`,
+				Computed:      true,
+				PlanModifiers: nodeRolesPlanModifiers,
 			},
-			"autoscaling": elasticsearchTopologyAutoscalingSchema(topologyAttributeName),
+			"autoscaling": elasticsearchTopologyAutoscalingSchema(options.tierName),
 		},
 	}
 }