apm-data: fix @custom component templates

Use `<data_stream.type>@custom` instead of `apm@custom`.
This is an enhancement over what Fleet sets up; it is
an additive improvement in the direction of
elastic#97664.

The rollup data streams' `@custom` component templates
now include the duration, like what Fleet sets up.

Add a YAML REST test, and a unit test ensuring consistency
across the index templates.

x-pack/plugin/apm-data/src/main/resources/index-templates/logs-apm.app@template.yaml

@@ -11,12 +11,12 @@ composed_of:
 - apm@mappings
 - apm@settings
 - apm-10d@lifecycle
-- apm@custom
+- logs@custom
 - logs-apm.app@custom
 - ecs@mappings
 ignore_missing_component_templates:
+- logs@custom
 - logs-apm.app@custom
-- apm@custom
 template:
   settings:
     index:

x-pack/plugin/apm-data/src/main/resources/index-templates/logs-apm.error@template.yaml

@@ -13,12 +13,12 @@ composed_of:
 - apm@settings
 - apm-10d@lifecycle
 - logs-apm.error@mappings
-- apm@custom
+- logs@custom
 - logs-apm.error@custom
 - ecs@mappings
 ignore_missing_component_templates:
+- logs@custom
 - logs-apm.error@custom
-- apm@custom
 template:
   mappings:
     properties:

x-pack/plugin/apm-data/src/main/resources/index-templates/metrics-apm.app@template.yaml

@@ -13,11 +13,11 @@ composed_of:
 - apm-90d@lifecycle
 - metrics-apm@mappings
 - metrics-apm@settings
-- apm@custom
+- metrics@custom
 - metrics-apm.app@custom
 - ecs@mappings
 ignore_missing_component_templates:
-- apm@custom
+- metrics@custom
 - metrics-apm.app@custom
 template:
   settings:

x-pack/plugin/apm-data/src/main/resources/index-templates/metrics-apm.internal@template.yaml

@@ -14,11 +14,11 @@ composed_of:
 - apm-90d@lifecycle
 - metrics-apm@mappings
 - metrics-apm@settings
-- apm@custom
+- metrics@custom
 - metrics-apm.internal@custom
 - ecs@mappings
 ignore_missing_component_templates:
-- apm@custom
+- metrics@custom
 - metrics-apm.internal@custom
 template:
   settings:

x-pack/plugin/apm-data/src/main/resources/index-templates/metrics-apm.service_destination.10m@template.yaml

@@ -16,12 +16,12 @@ composed_of:
 - metrics-apm@mappings
 - metrics-apm@settings
 - metrics-apm.service_destination@mappings
-- apm@custom
-- metrics-apm.service_destination@custom
+- metrics@custom
+- metrics-apm.service_destination.10m@custom
 - ecs@mappings
 ignore_missing_component_templates:
-- apm@custom
-- metrics-apm.service_destination@custom
+- metrics@custom
+- metrics-apm.service_destination.10m@custom
 template:
   settings:
     index:

x-pack/plugin/apm-data/src/main/resources/index-templates/metrics-apm.service_destination.1m@template.yaml

@@ -15,12 +15,12 @@ composed_of:
 - metrics-apm@mappings
 - metrics-apm@settings
 - metrics-apm.service_destination@mappings
-- apm@custom
-- metrics-apm.service_destination@custom
+- metrics@custom
+- metrics-apm.service_destination.1m@custom
 - ecs@mappings
 ignore_missing_component_templates:
-- apm@custom
-- metrics-apm.service_destination@custom
+- metrics@custom
+- metrics-apm.service_destination.1m@custom
 template:
   settings:
     index:

x-pack/plugin/apm-data/src/main/resources/index-templates/metrics-apm.service_destination.60m@template.yaml

@@ -16,12 +16,12 @@ composed_of:
 - metrics-apm@mappings
 - metrics-apm@settings
 - metrics-apm.service_destination@mappings
-- apm@custom
-- metrics-apm.service_destination@custom
+- metrics@custom
+- metrics-apm.service_destination.60m@custom
 - ecs@mappings
 ignore_missing_component_templates:
-- apm@custom
-- metrics-apm.service_destination@custom
+- metrics@custom
+- metrics-apm.service_destination.60m@custom
 template:
   settings:
     index:

x-pack/plugin/apm-data/src/main/resources/index-templates/metrics-apm.service_summary.10m@template.yaml

@@ -16,12 +16,12 @@ composed_of:
 - metrics-apm@mappings
 - metrics-apm@settings
 - metrics-apm.service_summary@mappings
-- apm@custom
-- metrics-apm.service_summary@custom
+- metrics@custom
+- metrics-apm.service_summary.10m@custom
 - ecs@mappings
 ignore_missing_component_templates:
-- apm@custom
-- metrics-apm.service_summary@custom
+- metrics@custom
+- metrics-apm.service_summary.10m@custom
 template:
   settings:
     index:

x-pack/plugin/apm-data/src/main/resources/index-templates/metrics-apm.service_summary.1m@template.yaml

@@ -15,12 +15,12 @@ composed_of:
 - metrics-apm@mappings
 - metrics-apm@settings
 - metrics-apm.service_summary@mappings
-- apm@custom
-- metrics-apm.service_summary@custom
+- metrics@custom
+- metrics-apm.service_summary.1m@custom
 - ecs@mappings
 ignore_missing_component_templates:
-- apm@custom
-- metrics-apm.service_summary@custom
+- metrics@custom
+- metrics-apm.service_summary.1m@custom
 template:
   settings:
     index:

x-pack/plugin/apm-data/src/main/resources/index-templates/metrics-apm.service_summary.60m@template.yaml

@@ -16,12 +16,12 @@ composed_of:
 - metrics-apm@mappings
 - metrics-apm@settings
 - metrics-apm.service_summary@mappings
-- apm@custom
-- metrics-apm.service_summary@custom
+- metrics@custom
+- metrics-apm.service_summary.60m@custom
 - ecs@mappings
 ignore_missing_component_templates:
-- apm@custom
-- metrics-apm.service_summary@custom
+- metrics@custom
+- metrics-apm.service_summary.60m@custom
 template:
   settings:
     index:

x-pack/plugin/apm-data/src/main/resources/index-templates/metrics-apm.service_transaction.10m@template.yaml

@@ -16,12 +16,12 @@ composed_of:
 - metrics-apm@mappings
 - metrics-apm@settings
 - metrics-apm.service_transaction@mappings
-- apm@custom
-- metrics-apm.service_transaction@custom
+- metrics@custom
+- metrics-apm.service_transaction.10m@custom
 - ecs@mappings
 ignore_missing_component_templates:
-- apm@custom
-- metrics-apm.service_transaction@custom
+- metrics@custom
+- metrics-apm.service_transaction.10m@custom
 template:
   settings:
     index:

x-pack/plugin/apm-data/src/main/resources/index-templates/metrics-apm.service_transaction.1m@template.yaml

@@ -15,12 +15,12 @@ composed_of:
 - metrics-apm@mappings
 - metrics-apm@settings
 - metrics-apm.service_transaction@mappings
-- apm@custom
-- metrics-apm.service_transaction@custom
+- metrics@custom
+- metrics-apm.service_transaction.1m@custom
 - ecs@mappings
 ignore_missing_component_templates:
-- apm@custom
-- metrics-apm.service_transaction@custom
+- metrics@custom
+- metrics-apm.service_transaction.1m@custom
 template:
   settings:
     index:

x-pack/plugin/apm-data/src/main/resources/index-templates/metrics-apm.service_transaction.60m@template.yaml

@@ -16,12 +16,12 @@ composed_of:
 - metrics-apm@mappings
 - metrics-apm@settings
 - metrics-apm.service_transaction@mappings
-- apm@custom
-- metrics-apm.service_transaction@custom
+- metrics@custom
+- metrics-apm.service_transaction.60m@custom
 - ecs@mappings
 ignore_missing_component_templates:
-- apm@custom
-- metrics-apm.service_transaction@custom
+- metrics@custom
+- metrics-apm.service_transaction.60m@custom
 template:
   settings:
     index:

x-pack/plugin/apm-data/src/main/resources/index-templates/metrics-apm.transaction.10m@template.yaml

@@ -16,12 +16,12 @@ composed_of:
 - metrics-apm@mappings
 - metrics-apm@settings
 - metrics-apm.transaction@mappings
-- apm@custom
-- metrics-apm.transaction@custom
+- metrics@custom
+- metrics-apm.transaction.10m@custom
 - ecs@mappings
 ignore_missing_component_templates:
-- apm@custom
-- metrics-apm.transaction@custom
+- metrics@custom
+- metrics-apm.transaction.10m@custom
 template:
   settings:
     index:

x-pack/plugin/apm-data/src/main/resources/index-templates/metrics-apm.transaction.1m@template.yaml

@@ -15,12 +15,12 @@ composed_of:
 - metrics-apm@mappings
 - metrics-apm@settings
 - metrics-apm.transaction@mappings
-- apm@custom
-- metrics-apm.transaction@custom
+- metrics@custom
+- metrics-apm.transaction.1m@custom
 - ecs@mappings
 ignore_missing_component_templates:
-- apm@custom
-- metrics-apm.transaction@custom
+- metrics@custom
+- metrics-apm.transaction.1m@custom
 template:
   settings:
     index:

x-pack/plugin/apm-data/src/main/resources/index-templates/metrics-apm.transaction.60m@template.yaml

@@ -16,12 +16,12 @@ composed_of:
 - metrics-apm@mappings
 - metrics-apm@settings
 - metrics-apm.transaction@mappings
-- apm@custom
-- metrics-apm.transaction@custom
+- metrics@custom
+- metrics-apm.transaction.60m@custom
 - ecs@mappings
 ignore_missing_component_templates:
-- apm@custom
-- metrics-apm.transaction@custom
+- metrics@custom
+- metrics-apm.transaction.60m@custom
 template:
   settings:
     index:

x-pack/plugin/apm-data/src/main/resources/index-templates/traces-apm.rum@template.yaml

@@ -14,14 +14,12 @@ composed_of:
 - apm-90d@lifecycle
 - traces-apm@mappings
 - traces-apm.rum@mappings
-- apm@custom
-- traces-apm@custom
+- traces@custom
 - traces-apm.rum@custom
 - ecs@mappings
 ignore_missing_component_templates:
+- traces@custom
 - traces-apm.rum@custom
-- traces-apm@custom
-- apm@custom
 template:
   settings:
     index:

x-pack/plugin/apm-data/src/main/resources/index-templates/traces-apm.sampled@template.yaml

@@ -11,10 +11,12 @@ composed_of:
 - traces@mappings
 - apm@mappings
 - apm@settings
-- apm@custom
+- traces@custom
+- traces-apm.sampled@custom
 - ecs@mappings
 ignore_missing_component_templates:
-- apm@custom
+- traces@custom
+- traces-apm.sampled@custom
 template:
   lifecycle:
     data_retention: 1h

x-pack/plugin/apm-data/src/main/resources/index-templates/traces-apm@template.yaml

@@ -13,12 +13,12 @@ composed_of:
 - apm@settings
 - apm-10d@lifecycle
 - traces-apm@mappings
-- apm@custom
+- traces@custom
 - traces-apm@custom
 - ecs@mappings
 ignore_missing_component_templates:
+- traces@custom
 - traces-apm@custom
-- apm@custom
 template:
   settings:
     index:

x-pack/plugin/apm-data/src/test/java/org/elasticsearch/xpack/apmdata/APMIndexTemplateRegistryTests.java

@@ -57,10 +57,12 @@
 import java.util.stream.Collectors;
 
 import static org.elasticsearch.xpack.core.XPackSettings.APM_DATA_ENABLED;
+import static org.hamcrest.Matchers.containsInAnyOrder;
 import static org.hamcrest.Matchers.empty;
 import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.instanceOf;
 import static org.hamcrest.Matchers.is;
+import static org.hamcrest.Matchers.isIn;
 import static org.hamcrest.Matchers.not;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.spy;
@@ -249,6 +251,48 @@ public void testIndexTemplates() throws Exception {
         assertThat(actualInstalledIngestPipelines.get(), equalTo(0));
     }
 
+    public void testIndexTemplateConventions() throws Exception {
+        for (Map.Entry<String, ComposableIndexTemplate> entry : apmIndexTemplateRegistry.getComposableTemplateConfigs().entrySet()) {
+            final String name = entry.getKey();
+            final int atIndex = name.lastIndexOf('@');
+            assertThat(atIndex, not(equalTo(-1)));
+            assertThat(name.substring(atIndex + 1), equalTo("template"));
+
+            final String dataStreamType = name.substring(0, name.indexOf('-'));
+            assertThat(dataStreamType, isIn(List.of("logs", "metrics", "traces")));
+
+            final ComposableIndexTemplate template = entry.getValue();
+            assertThat(template.indexPatterns().size(), equalTo(1));
+
+            final String namePrefix = name.substring(0, atIndex);
+            switch (namePrefix) {
+                case "logs-apm.app", "metrics-apm.app":
+                    // These two data streams have a service-specific dataset.
+                    assertThat(template.indexPatterns().get(0), equalTo(namePrefix + ".*-*"));
+                    break;
+                default:
+                    assertThat(template.indexPatterns().get(0), equalTo(namePrefix + "-*"));
+                    break;
+            }
+
+            // Each index template should be composed of the following optional component templates:
+            // <data_stream.type>@custom
+            // <data_stream.type>-<data_stream.dataset>@custom
+            final List<String> optionalComponentTemplates = template.composedOf()
+                .stream()
+                .filter(t -> template.getIgnoreMissingComponentTemplates().contains(t))
+                .toList();
+            assertThat(optionalComponentTemplates, containsInAnyOrder(namePrefix + "@custom", dataStreamType + "@custom"));
+
+            // There should be no required custom component templates.
+            final List<String> requiredCustomComponentTemplates = template.getRequiredComponentTemplates()
+                .stream()
+                .filter(t -> t.endsWith("@custom"))
+                .toList();
+            assertThat(requiredCustomComponentTemplates, empty());
+        }
+    }
+
     private Map<String, ComponentTemplate> getIndependentComponentTemplateConfigs() {
         return apmIndexTemplateRegistry.getComponentTemplateConfigs().entrySet().stream().filter(template -> {
             Settings settings = template.getValue().template().settings();