Bump to version 8.9.0

.backportrc.json

@@ -1,9 +1,9 @@
 {
   "upstream" : "elastic/elasticsearch",
-  "targetBranchChoices" : [ "main", "8.7", "8.6", "8.5", "8.4", "8.3", "8.2", "8.1", "8.0", "7.17", "6.8" ],
+  "targetBranchChoices" : [ "main", "8.8", "8.7", "8.6", "8.5", "8.4", "8.3", "8.2", "8.1", "8.0", "7.17", "6.8" ],
   "targetPRLabels" : [ "backport" ],
   "branchLabelMapping" : {
-    "^v8.8.0$" : "main",
+    "^v8.9.0$" : "main",
     "^v(\\d+).(\\d+).\\d+(?:-(?:alpha|beta|rc)\\d+)?$" : "$1.$2"
   }
 }

.ci/bwcVersions

@@ -87,3 +87,4 @@ BWC_VERSION:
   - "8.7.0"
   - "8.7.1"
   - "8.8.0"
+  - "8.9.0"

.ci/snapshotBwcVersions

@@ -2,3 +2,4 @@ BWC_VERSION:
   - "7.17.10"
   - "8.7.1"
   - "8.8.0"
+  - "8.9.0"

build-tools-internal/version.properties

@@ -1,4 +1,4 @@
-elasticsearch     = 8.8.0
+elasticsearch     = 8.9.0
 lucene            = 9.6.0-snapshot-dcc2154a1d3
 
 bundled_jdk_vendor = openjdk

docs/reference/migration/index.asciidoc

@@ -1,5 +1,6 @@
 include::migration_intro.asciidoc[]
 
+* <<migrating-8.9,Migrating to 8.9>>
 * <<migrating-8.8,Migrating to 8.8>>
 * <<migrating-8.7,Migrating to 8.7>>
 * <<migrating-8.6,Migrating to 8.6>>
@@ -10,6 +11,7 @@ include::migration_intro.asciidoc[]
 * <<migrating-8.1,Migrating to 8.1>>
 * <<migrating-8.0,Migrating to 8.0>>
 
+include::migrate_8_9.asciidoc[]
 include::migrate_8_8.asciidoc[]
 include::migrate_8_7.asciidoc[]
 include::migrate_8_6.asciidoc[]

docs/reference/migration/migrate_8_9.asciidoc

@@ -0,0 +1,22 @@
+[[migrating-8.9]]
+== Migrating to 8.9
+++++
+<titleabbrev>8.9</titleabbrev>
+++++
+
+This section discusses the changes that you need to be aware of when migrating
+your application to {es} 8.9.
+
+See also <<release-highlights>> and <<es-release-notes>>.
+
+coming::[8.9.0]
+
+
+[discrete]
+[[breaking-changes-8.9]]
+=== Breaking changes
+
+// tag::notable-breaking-changes[]
+There are no breaking changes in {es} 8.9.
+// end::notable-breaking-changes[]
+

docs/reference/release-notes.asciidoc

@@ -6,6 +6,7 @@
 
 This section summarizes the changes in each release.
 
+* <<release-notes-8.9.0>>
 * <<release-notes-8.8.0>>
 * <<release-notes-8.7.0>>
 * <<release-notes-8.6.2>>
@@ -41,6 +42,7 @@ This section summarizes the changes in each release.
 
 --
 
+include::release-notes/8.9.0.asciidoc[]
 include::release-notes/8.8.0.asciidoc[]
 include::release-notes/8.7.0.asciidoc[]
 include::release-notes/8.6.2.asciidoc[]

docs/reference/release-notes/8.9.0.asciidoc

@@ -0,0 +1,8 @@
+[[release-notes-8.9.0]]
+== {es} version 8.9.0
+
+coming[8.9.0]
+
+Also see <<breaking-changes-8.9,Breaking changes in 8.9>>.
+
+

docs/reference/release-notes/highlights.asciidoc

@@ -12,7 +12,8 @@ endif::[]
 // Add previous release to the list
 Other versions:
 
-{ref-bare}/8.7/release-highlights.html[8.7]
+{ref-bare}/8.8/release-highlights.html[8.8]
+| {ref-bare}/8.7/release-highlights.html[8.7]
 | {ref-bare}/8.6/release-highlights.html[8.6]
 | {ref-bare}/8.5/release-highlights.html[8.5]
 | {ref-bare}/8.4/release-highlights.html[8.4]
@@ -21,28 +22,13 @@ Other versions:
 | {ref-bare}/8.1/release-highlights.html[8.1]
 | {ref-bare}/8.0/release-highlights.html[8.0]
 
+// The notable-highlights tag marks entries that
+// should be featured in the Stack Installation and Upgrade Guide:
 // tag::notable-highlights[]
-
-[discrete]
-[[add_new_similarity_field_to_knn_clause_in_search]]
-=== Add new `similarity` field to `knn` clause in `_search`
-This adds a new parameter to `knn` that allows filtering nearest
-neighbor results that are outside a given similarity.
-
-`num_candidates` and `k` are still required as this controls the
-nearest-neighbor vector search accuracy and exploration. For each shard
-the query will search `num_candidates` and only keep those that are
-within the provided `similarity` boundary, and then finally reduce to
-only the global top `k` as normal.
-
-For example, when using the `l2_norm` indexed similarity value, this
-could be considered a `radius` post-filter on `knn`.
-
-relates to: https://github.com/elastic/elasticsearch/issues/84929 &&
-https://github.com/elastic/elasticsearch/pull/93574
-
-{es-pull}94828[#94828]
-
+// [discrete]
+// === Heading
+//
+// Description.
 // end::notable-highlights[]
 
 

server/src/main/java/org/elasticsearch/TransportVersion.java

@@ -135,6 +135,7 @@ public class TransportVersion implements Comparable<TransportVersion> {
     public static final TransportVersion V_8_7_0 = new TransportVersion(8_07_00_99, "f1ee7a85-4fa6-43f5-8679-33e2b750448b");
     public static final TransportVersion V_8_7_1 = new TransportVersion(8_07_01_99, "018de9d8-9e8b-4ac7-8f4b-3a6fbd0487fb");
     public static final TransportVersion V_8_8_0 = new TransportVersion(8_08_00_99, "f64fe576-0767-4ec3-984e-3e30b33b6c46");
+    public static final TransportVersion V_8_9_0 = new TransportVersion(8_09_00_99, "13c1c2cb-d975-461f-ab98-309ebc1c01bc");
     /*
      * READ THE JAVADOC ABOVE BEFORE ADDING NEW TRANSPORT VERSIONS
      * Detached transport versions added below here. Starts at ES major version 10 equivalent.
@@ -150,7 +151,7 @@ public class TransportVersion implements Comparable<TransportVersion> {
      */
 
     /** Reference to the current transport version */
-    public static final TransportVersion CURRENT = V_8_8_0;
+    public static final TransportVersion CURRENT = V_8_9_0;
 
     /** Reference to the earliest compatible transport version to this version of the codebase */
     // TODO: can we programmatically calculate or check this? Don't want to introduce circular ref between Version/TransportVersion

server/src/main/java/org/elasticsearch/Version.java

@@ -140,7 +140,8 @@ public class Version implements Comparable<Version>, ToXContentFragment {
     public static final Version V_8_7_1 = new Version(8_07_01_99, TransportVersion.V_8_7_1, org.apache.lucene.util.Version.LUCENE_9_5_0);
 
     public static final Version V_8_8_0 = new Version(8_08_00_99, TransportVersion.V_8_8_0, org.apache.lucene.util.Version.LUCENE_9_6_0);
-    public static final Version CURRENT = V_8_8_0;
+    public static final Version V_8_9_0 = new Version(8_09_00_99, TransportVersion.V_8_9_0, org.apache.lucene.util.Version.LUCENE_9_6_0);
+    public static final Version CURRENT = V_8_9_0;
 
     private static final NavigableMap<Integer, Version> VERSION_IDS;
     private static final Map<String, Version> VERSION_STRINGS;