Enable bwc tests and adjust versioning. (#66004)

Relates to #64710

Author: martijnvg

build.gradle

@@ -175,8 +175,8 @@ tasks.register("verifyVersions") {
  * after the backport of the backcompat code is complete.
  */
 
-boolean bwc_tests_enabled = false
-final String bwc_tests_disabled_issue = "https://github.com/elastic/elasticsearch/pull/65999" /* place a PR link here when committing bwc changes */
+boolean bwc_tests_enabled = true
+final String bwc_tests_disabled_issue = "" /* place a PR link here when committing bwc changes */
 if (bwc_tests_enabled == false) {
   if (bwc_tests_disabled_issue.isEmpty()) {
     throw new GradleException("bwc_tests_disabled_issue must be set when bwc_tests_enabled == false")

server/src/main/java/org/elasticsearch/cluster/metadata/ComposableIndexTemplate.java

@@ -300,7 +300,7 @@ public DataStreamTemplate(boolean hidden) {
         }
 
         DataStreamTemplate(StreamInput in) throws IOException {
-            hidden = in.getVersion().onOrAfter(DataStream.HIDDEN_VERSION) && in.readBoolean();
+            hidden = in.getVersion().onOrAfter(DataStream.NEW_DS_VERSION) && in.readBoolean();
         }
 
         public String getTimestampField() {
@@ -321,7 +321,7 @@ public boolean isHidden() {
 
         @Override
         public void writeTo(StreamOutput out) throws IOException {
-            if (out.getVersion().onOrAfter(DataStream.HIDDEN_VERSION)) {
+            if (out.getVersion().onOrAfter(DataStream.NEW_DS_VERSION)) {
                 out.writeBoolean(hidden);
             }
         }

server/src/main/java/org/elasticsearch/cluster/metadata/DataStream.java

@@ -43,8 +43,11 @@
 public final class DataStream extends AbstractDiffable<DataStream> implements ToXContentObject {
 
     public static final String BACKING_INDEX_PREFIX = ".ds-";
-    public static final Version HIDDEN_VERSION = Version.V_7_11_0;
-    public static final Version REPLICATED_VERSION = Version.V_8_0_0;
+
+    /**
+     * The version when data stream metadata, hidden data streams and replicated data streams was introduced.
+     */
+    public static final Version NEW_DS_VERSION = Version.V_7_11_0;
 
     private final String name;
     private final TimestampField timeStampField;
@@ -190,9 +193,9 @@ public static String getDefaultBackingIndexName(String dataStreamName, long gene
 
     public DataStream(StreamInput in) throws IOException {
         this(in.readString(), new TimestampField(in), in.readList(Index::new), in.readVLong(),
-            in.getVersion().onOrAfter(Version.V_7_11_0) ? in.readMap(): null,
-            in.getVersion().onOrAfter(HIDDEN_VERSION) && in.readBoolean(),
-            in.getVersion().onOrAfter(REPLICATED_VERSION) && in.readBoolean());
+            in.getVersion().onOrAfter(NEW_DS_VERSION) ? in.readMap(): null,
+            in.getVersion().onOrAfter(NEW_DS_VERSION) && in.readBoolean(),
+            in.getVersion().onOrAfter(NEW_DS_VERSION) && in.readBoolean());
     }
 
     public static Diff<DataStream> readDiffFrom(StreamInput in) throws IOException {
@@ -205,13 +208,9 @@ public void writeTo(StreamOutput out) throws IOException {
         timeStampField.writeTo(out);
         out.writeList(indices);
         out.writeVLong(generation);
-        if (out.getVersion().onOrAfter(Version.V_7_11_0)) {
+        if (out.getVersion().onOrAfter(NEW_DS_VERSION)) {
             out.writeMap(metadata);
-        }
-        if (out.getVersion().onOrAfter(HIDDEN_VERSION)) {
             out.writeBoolean(hidden);
-        }
-        if (out.getVersion().onOrAfter(REPLICATED_VERSION)) {
             out.writeBoolean(replicated);
         }
     }

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/action/DeleteDataStreamAction.java

@@ -68,7 +68,7 @@ public Request(StreamInput in) throws IOException {
             super(in);
             this.names = in.readStringArray();
             this.wildcardExpressionsOriginallySpecified = in.getVersion().onOrAfter(Version.V_7_10_0) && in.readBoolean();
-            if (in.getVersion().onOrAfter(DataStream.HIDDEN_VERSION)) {
+            if (in.getVersion().onOrAfter(DataStream.NEW_DS_VERSION)) {
                 this.indicesOptions = IndicesOptions.readIndicesOptions(in);
             }
         }
@@ -80,7 +80,7 @@ public void writeTo(StreamOutput out) throws IOException {
             if (out.getVersion().onOrAfter(Version.V_7_10_0)) {
                 out.writeBoolean(wildcardExpressionsOriginallySpecified);
             }
-            if (out.getVersion().onOrAfter(DataStream.HIDDEN_VERSION)) {
+            if (out.getVersion().onOrAfter(DataStream.NEW_DS_VERSION)) {
                 indicesOptions.writeIndicesOptions(out);
             }
         }

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/action/GetDataStreamAction.java

@@ -56,7 +56,7 @@ public ActionRequestValidationException validate() {
         public Request(StreamInput in) throws IOException {
             super(in);
             this.names = in.readOptionalStringArray();
-            if (in.getVersion().onOrAfter(DataStream.HIDDEN_VERSION)) {
+            if (in.getVersion().onOrAfter(DataStream.NEW_DS_VERSION)) {
                 this.indicesOptions = IndicesOptions.readIndicesOptions(in);
             }
         }
@@ -65,7 +65,7 @@ public Request(StreamInput in) throws IOException {
         public void writeTo(StreamOutput out) throws IOException {
             super.writeTo(out);
             out.writeOptionalStringArray(names);
-            if (out.getVersion().onOrAfter(DataStream.HIDDEN_VERSION)) {
+            if (out.getVersion().onOrAfter(DataStream.NEW_DS_VERSION)) {
                 indicesOptions.writeIndicesOptions(out);
             }
         }