Adding ignore_missing_component_templates (#1206)

* Adding ignore_missing_component_templates
#631

* Trigger workflow

* Reverting trigger change

* Adding acceptance tests on index template for parameter ignore_missing_component_templates

* Updating changelog

* Handling inconsistent tabs vs spaces

* Handling inconsistent tabs vs spaces

* es version awareness ignore_missing_component_templates

* Formatting

* Updating ressource ref from data source test

* Update Changelog

---------

Co-authored-by: Toby Brain <toby.brain@elastic.co>
Co-authored-by: Toby Brain <tobio85@gmail.com>

Author: togish

CHANGELOG.md

@@ -1,5 +1,7 @@
 ## [Unreleased]
 
+- Add `ignore_missing_component_templates` to `elasticstack_elasticsearch_index_template` ([#1206](https://github.com/elastic/terraform-provider-elasticstack/pull/1206))
+
 ## [0.11.17] - 2025-07-21
 
 - Add `elasticstack_apm_agent_configuration` resource ([#1196](https://github.com/elastic/terraform-provider-elasticstack/pull/1196))

docs/data-sources/elasticsearch_index_template.md

@@ -42,6 +42,7 @@ output "template" {
 - `composed_of` (List of String) An ordered list of component template names.
 - `data_stream` (List of Object) If this object is included, the template is used to create data streams and their backing indices. Supports an empty object. (see [below for nested schema](#nestedatt--data_stream))
 - `id` (String) Internal identifier of the resource
+- `ignore_missing_component_templates` (List of String) A list of component template names that are ignored if missing.
 - `index_patterns` (Set of String) Array of wildcard (*) expressions used to match the names of data streams and indices during creation.
 - `metadata` (String) Optional user metadata about the index template.
 - `priority` (Number) Priority to determine index template precedence when a new data stream or index is created.

docs/resources/elasticsearch_index_template.md

@@ -58,6 +58,7 @@ resource "elasticstack_elasticsearch_index_template" "my_data_stream" {
 - `composed_of` (List of String) An ordered list of component template names.
 - `data_stream` (Block List, Max: 1) If this object is included, the template is used to create data streams and their backing indices. Supports an empty object. (see [below for nested schema](#nestedblock--data_stream))
 - `elasticsearch_connection` (Block List, Max: 1, Deprecated) Elasticsearch connection configuration block. This property will be removed in a future provider version. Configure the Elasticsearch connection via the provider configuration instead. (see [below for nested schema](#nestedblock--elasticsearch_connection))
+- `ignore_missing_component_templates` (List of String) A list of component template names that are ignored if missing.
 - `metadata` (String) Optional user metadata about the index template.
 - `priority` (Number) Priority to determine index template precedence when a new data stream or index is created.
 - `template` (Block List, Max: 1) Template to be applied. It may optionally include an aliases, mappings, lifecycle, or settings configuration. (see [below for nested schema](#nestedblock--template))

internal/elasticsearch/index/template.go

@@ -10,12 +10,17 @@ import (
 	"github.com/elastic/terraform-provider-elasticstack/internal/clients/elasticsearch"
 	"github.com/elastic/terraform-provider-elasticstack/internal/models"
 	"github.com/elastic/terraform-provider-elasticstack/internal/utils"
+	"github.com/hashicorp/go-version"
 	"github.com/hashicorp/terraform-plugin-log/tflog"
 	"github.com/hashicorp/terraform-plugin-sdk/v2/diag"
 	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema"
 	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/validation"
 )
 
+var (
+	MinSupportedIgnoreMissingComponentTemplateVersion = version.Must(version.NewVersion("8.7.0"))
+)
+
 func ResourceTemplate() *schema.Resource {
 	templateSchema := map[string]*schema.Schema{
 		"id": {
@@ -38,6 +43,15 @@ func ResourceTemplate() *schema.Resource {
 				Type: schema.TypeString,
 			},
 		},
+		"ignore_missing_component_templates": {
+			Description: "A list of component template names that are ignored if missing.",
+			Type:        schema.TypeList,
+			Optional:    true,
+			Computed:    true,
+			Elem: &schema.Schema{
+				Type: schema.TypeString,
+			},
+		},
 		"data_stream": {
 			Description: "If this object is included, the template is used to create data streams and their backing indices. Supports an empty object.",
 			Type:        schema.TypeList,
@@ -210,6 +224,12 @@ func resourceIndexTemplatePut(ctx context.Context, d *schema.ResourceData, meta
 	if diags.HasError() {
 		return diags
 	}
+
+	serverVersion, diags := client.ServerVersion(ctx)
+	if diags.HasError() {
+		return diags
+	}
+
 	var indexTemplate models.IndexTemplate
 	indexTemplate.Name = templateId
 
@@ -221,6 +241,18 @@ func resourceIndexTemplatePut(ctx context.Context, d *schema.ResourceData, meta
 	}
 	indexTemplate.ComposedOf = compsOf
 
+	if v, ok := d.GetOk("ignore_missing_component_templates"); ok {
+		compsOfIgnore := make([]string, 0)
+		for _, c := range v.([]interface{}) {
+			compsOfIgnore = append(compsOfIgnore, c.(string))
+		}
+
+		if len(compsOfIgnore) > 0 && serverVersion.LessThan(MinSupportedIgnoreMissingComponentTemplateVersion) {
+			return diag.FromErr(fmt.Errorf("'ignore_missing_component_templates' is supported only for Elasticsearch v%s and above", MinSupportedIgnoreMissingComponentTemplateVersion.String()))
+		}
+		indexTemplate.IgnoreMissingComponentTemplates = compsOfIgnore
+	}
+
 	if v, ok := d.GetOk("data_stream"); ok {
 		// 8.x workaround
 		hasAllowCustomRouting := false
@@ -371,6 +403,9 @@ func resourceIndexTemplateRead(ctx context.Context, d *schema.ResourceData, meta
 	if err := d.Set("composed_of", tpl.IndexTemplate.ComposedOf); err != nil {
 		return diag.FromErr(err)
 	}
+	if err := d.Set("ignore_missing_component_templates", tpl.IndexTemplate.IgnoreMissingComponentTemplates); err != nil {
+		return diag.FromErr(err)
+	}
 	if stream := tpl.IndexTemplate.DataStream; stream != nil {
 		ds := make([]interface{}, 1)
 		dSettings := make(map[string]interface{})

internal/elasticsearch/index/template_data_source.go

@@ -29,6 +29,14 @@ func DataSourceTemplate() *schema.Resource {
 				Type: schema.TypeString,
 			},
 		},
+		"ignore_missing_component_templates": {
+			Description: "A list of component template names that are ignored if missing.",
+			Type:        schema.TypeList,
+			Computed:    true,
+			Elem: &schema.Schema{
+				Type: schema.TypeString,
+			},
+		},
 		"data_stream": {
 			Description: "If this object is included, the template is used to create data streams and their backing indices. Supports an empty object.",
 			Type:        schema.TypeList,

internal/elasticsearch/index/template_data_source_test.go

@@ -5,13 +5,16 @@ import (
 	"testing"
 
 	"github.com/elastic/terraform-provider-elasticstack/internal/acctest"
+	"github.com/elastic/terraform-provider-elasticstack/internal/elasticsearch/index"
+	"github.com/elastic/terraform-provider-elasticstack/internal/versionutils"
 	sdkacctest "github.com/hashicorp/terraform-plugin-sdk/v2/helper/acctest"
 	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/resource"
 )
 
 func TestAccIndexTemplateDataSource(t *testing.T) {
 	// generate a random role name
 	templateName := "test-template-" + sdkacctest.RandStringFromCharSet(10, sdkacctest.CharSetAlphaNum)
+	templateNameComponent := "test-template-" + sdkacctest.RandStringFromCharSet(10, sdkacctest.CharSetAlphaNum)
 
 	resource.Test(t, resource.TestCase{
 		PreCheck:                 func() { acctest.PreCheck(t) },
@@ -25,6 +28,16 @@ func TestAccIndexTemplateDataSource(t *testing.T) {
 					resource.TestCheckResourceAttr("data.elasticstack_elasticsearch_index_template.test", "priority", "100"),
 				),
 			},
+			{
+				SkipFunc: versionutils.CheckIfVersionIsUnsupported(index.MinSupportedIgnoreMissingComponentTemplateVersion),
+				Config:   testAccIndexTemplateDataSourceWithIgnoreComponentConfig(templateNameComponent),
+				Check: resource.ComposeAggregateTestCheckFunc(
+					resource.TestCheckResourceAttr("data.elasticstack_elasticsearch_index_template.test_component", "name", templateNameComponent),
+					resource.TestCheckTypeSetElemAttr("data.elasticstack_elasticsearch_index_template.test_component", "index_patterns.*", fmt.Sprintf("tf-acc-component-%s-*", templateNameComponent)),
+					resource.TestCheckTypeSetElemAttr("data.elasticstack_elasticsearch_index_template.test_component", "composed_of.*", fmt.Sprintf("%s-logscomponent@custom", templateNameComponent)),
+					resource.TestCheckTypeSetElemAttr("data.elasticstack_elasticsearch_index_template.test_component", "ignore_missing_component_templates.*", fmt.Sprintf("%s-logscomponent@custom", templateNameComponent)),
+				),
+			},
 		},
 	})
 }
@@ -47,3 +60,22 @@ data "elasticstack_elasticsearch_index_template" "test" {
 }
 	`, templateName, templateName)
 }
+
+func testAccIndexTemplateDataSourceWithIgnoreComponentConfig(templateName string) string {
+	return fmt.Sprintf(`
+provider "elasticstack" {
+	elasticsearch {}
+}
+
+resource "elasticstack_elasticsearch_index_template" "test_component" {
+	name = "%s"
+	index_patterns = ["tf-acc-component-%s-*"]
+	composed_of = ["%s-logscomponent@custom"]
+	ignore_missing_component_templates = ["%s-logscomponent@custom"]
+}
+
+data "elasticstack_elasticsearch_index_template" "test_component" {
+	name = elasticstack_elasticsearch_index_template.test_component.name
+}
+	`, templateName, templateName, templateName, templateName)
+}

internal/elasticsearch/index/template_test.go

@@ -6,6 +6,8 @@ import (
 
 	"github.com/elastic/terraform-provider-elasticstack/internal/acctest"
 	"github.com/elastic/terraform-provider-elasticstack/internal/clients"
+	"github.com/elastic/terraform-provider-elasticstack/internal/elasticsearch/index"
+	"github.com/elastic/terraform-provider-elasticstack/internal/versionutils"
 	sdkacctest "github.com/hashicorp/terraform-plugin-sdk/v2/helper/acctest"
 	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/resource"
 	"github.com/hashicorp/terraform-plugin-sdk/v2/terraform"
@@ -14,6 +16,7 @@ import (
 func TestAccResourceIndexTemplate(t *testing.T) {
 	// generate random template name
 	templateName := sdkacctest.RandStringFromCharSet(10, sdkacctest.CharSetAlphaNum)
+	templateNameComponent := sdkacctest.RandStringFromCharSet(10, sdkacctest.CharSetAlphaNum)
 
 	resource.Test(t, resource.TestCase{
 		PreCheck:                 func() { acctest.PreCheck(t) },
@@ -41,6 +44,26 @@ func TestAccResourceIndexTemplate(t *testing.T) {
 					resource.TestCheckResourceAttr("elasticstack_elasticsearch_index_template.test2", "data_stream.0.hidden", "false"),
 				),
 			},
+			{
+				SkipFunc: versionutils.CheckIfVersionIsUnsupported(index.MinSupportedIgnoreMissingComponentTemplateVersion),
+				Config:   testAccResourceIndexTemplateCreateWithIgnoreComponent(templateNameComponent),
+				Check: resource.ComposeTestCheckFunc(
+					resource.TestCheckResourceAttr("elasticstack_elasticsearch_index_template.test_component", "name", templateNameComponent),
+					resource.TestCheckTypeSetElemAttr("elasticstack_elasticsearch_index_template.test_component", "index_patterns.*", fmt.Sprintf("%s-logscomponent-*", templateNameComponent)),
+					resource.TestCheckTypeSetElemAttr("elasticstack_elasticsearch_index_template.test_component", "composed_of.*", fmt.Sprintf("%s-logscomponent@custom", templateNameComponent)),
+					resource.TestCheckTypeSetElemAttr("elasticstack_elasticsearch_index_template.test_component", "ignore_missing_component_templates.*", fmt.Sprintf("%s-logscomponent@custom", templateNameComponent)),
+				),
+			},
+			{
+				SkipFunc: versionutils.CheckIfVersionIsUnsupported(index.MinSupportedIgnoreMissingComponentTemplateVersion),
+				Config:   testAccResourceIndexTemplateUpdateWithIgnoreComponent(templateNameComponent),
+				Check: resource.ComposeTestCheckFunc(
+					resource.TestCheckResourceAttr("elasticstack_elasticsearch_index_template.test_component", "name", templateNameComponent),
+					resource.TestCheckTypeSetElemAttr("elasticstack_elasticsearch_index_template.test_component", "index_patterns.*", fmt.Sprintf("%s-logscomponent-*", templateNameComponent)),
+					resource.TestCheckTypeSetElemAttr("elasticstack_elasticsearch_index_template.test_component", "composed_of.*", fmt.Sprintf("%s-logscomponent-updated@custom", templateNameComponent)),
+					resource.TestCheckTypeSetElemAttr("elasticstack_elasticsearch_index_template.test_component", "ignore_missing_component_templates.*", fmt.Sprintf("%s-logscomponent-updated@custom", templateNameComponent)),
+				),
+			},
 		},
 	})
 }
@@ -117,6 +140,41 @@ resource "elasticstack_elasticsearch_index_template" "test2" {
 	`, name, name, name)
 }
 
+func testAccResourceIndexTemplateCreateWithIgnoreComponent(name string) string {
+	return fmt.Sprintf(`
+provider "elasticstack" {
+  elasticsearch {}
+}
+
+resource "elasticstack_elasticsearch_index_template" "test_component" {
+  name = "%s"
+	index_patterns = ["%s-logscomponent-*"]
+
+  composed_of = ["%s-logscomponent@custom"]
+  ignore_missing_component_templates = ["%s-logscomponent@custom"]
+}
+	`, name, name, name, name)
+}
+
+func testAccResourceIndexTemplateUpdateWithIgnoreComponent(name string) string {
+	return fmt.Sprintf(`
+provider "elasticstack" {
+  elasticsearch {}
+}
+
+resource "elasticstack_elasticsearch_index_template" "test_component" {
+  name = "%s"
+	index_patterns = ["%s-logscomponent-*"]
+
+  composed_of = ["%s-logscomponent-updated@custom"]
+  ignore_missing_component_templates = ["%s-logscomponent-updated@custom"]
+
+  template {
+  }
+}
+	`, name, name, name, name)
+}
+
 func checkResourceIndexTemplateDestroy(s *terraform.State) error {
 	client, err := clients.NewAcceptanceTestingClient()
 	if err != nil {

internal/models/models.go

@@ -163,16 +163,17 @@ type Application struct {
 }
 
 type IndexTemplate struct {
-	Name          string                 `json:"-"`
-	Create        bool                   `json:"-"`
-	Timeout       string                 `json:"-"`
-	ComposedOf    []string               `json:"composed_of"`
-	DataStream    *DataStreamSettings    `json:"data_stream,omitempty"`
-	IndexPatterns []string               `json:"index_patterns"`
-	Meta          map[string]interface{} `json:"_meta,omitempty"`
-	Priority      *int                   `json:"priority,omitempty"`
-	Template      *Template              `json:"template,omitempty"`
-	Version       *int                   `json:"version,omitempty"`
+	Name                            string                 `json:"-"`
+	Create                          bool                   `json:"-"`
+	Timeout                         string                 `json:"-"`
+	ComposedOf                      []string               `json:"composed_of"`
+	IgnoreMissingComponentTemplates []string               `json:"ignore_missing_component_templates,omitempty"`
+	DataStream                      *DataStreamSettings    `json:"data_stream,omitempty"`
+	IndexPatterns                   []string               `json:"index_patterns"`
+	Meta                            map[string]interface{} `json:"_meta,omitempty"`
+	Priority                        *int                   `json:"priority,omitempty"`
+	Template                        *Template              `json:"template,omitempty"`
+	Version                         *int                   `json:"version,omitempty"`
 }
 
 type DataStreamSettings struct {