Adds support for templates index pattern

code/go/internal/validator/test/packages/good/data_stream/foo/manifest.yml

@@ -28,6 +28,7 @@ streams:
         default: /server-status
     title: Nginx access logs
     description: Collect Nginx access logs
+dataset_is_prefix: true
 elasticsearch.index_template.mappings:
   a:
     b: 1

versions/1/changelog.yml

@@ -48,4 +48,7 @@
     link: https://github.com/elastic/package-spec/pull/104
   - description: Add field for skipping tests.
     type: enhancement
-    link: https://github.com/elastic/package-spec/pull/105
+    link: https://github.com/elastic/package-spec/pull/105
+  - description: Add fields for matching datasets dynamically
+    type: enhancement
+    link: https://github.com/elastic/package-spec/pull/102

versions/1/data_stream/manifest.spec.yml

@@ -111,6 +111,10 @@ spec:
       type: string
       examples:
       - diagnostics
+    dataset_is_prefix:
+      description: if true, the index pattern in the ES template will contain the dataset as a prefix only
+      type: boolean
+      default: false
     type:
       description: Type of data stream
       type: string