Move per-project settings out of ProjectMetadata

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

@@ -285,6 +285,7 @@ static TransportVersion def(int id) {
     public static final TransportVersion ILM_ADD_SKIP_SETTING = def(9_089_0_00);
     public static final TransportVersion ML_INFERENCE_MISTRAL_CHAT_COMPLETION_ADDED = def(9_090_0_00);
     public static final TransportVersion IDP_CUSTOM_SAML_ATTRIBUTES_ALLOW_LIST = def(9_091_0_00);
+    public static final TransportVersion CLUSTER_STATE_PROJECTS_SETTINGS = def(9_092_0_00);
 
     /*
      * STOP! READ THIS FIRST! No, really,

server/src/main/java/org/elasticsearch/action/admin/cluster/state/TransportClusterStateAction.java

@@ -201,6 +201,7 @@ private ClusterStateResponse buildResponse(final ClusterStateRequest request, fi
         ClusterState.Builder builder = ClusterState.builder(currentState.getClusterName());
         builder.version(currentState.version());
         builder.stateUUID(currentState.stateUUID());
+        builder.projectsSettings(currentState.projectsSettings());
 
         if (request.nodes()) {
             builder.nodes(currentState.nodes());

server/src/main/java/org/elasticsearch/cluster/ClusterState.java

@@ -47,6 +47,7 @@
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.io.stream.VersionedNamedWriteable;
 import org.elasticsearch.common.io.stream.Writeable;
+import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.util.Maps;
 import org.elasticsearch.common.xcontent.ChunkedToXContent;
 import org.elasticsearch.common.xcontent.ChunkedToXContentHelper;
@@ -192,6 +193,8 @@ public CompatibilityVersions read(StreamInput in, String key) throws IOException
 
     private final boolean wasReadFromDiff;
 
+    private final Map<ProjectId, Settings> projectsSettings;
+
     // built on demand
     private volatile RoutingNodes routingNodes;
 
@@ -208,6 +211,7 @@ public ClusterState(long version, String stateUUID, ClusterState state) {
             state.blocks(),
             state.customs(),
             false,
+            state.projectsSettings,
             state.routingNodes
         );
     }
@@ -224,6 +228,7 @@ public ClusterState(
         ClusterBlocks blocks,
         Map<String, Custom> customs,
         boolean wasReadFromDiff,
+        Map<ProjectId, Settings> projectsSettings,
         @Nullable RoutingNodes routingNodes
     ) {
         this.version = version;
@@ -237,6 +242,7 @@ public ClusterState(
         this.blocks = blocks;
         this.customs = customs;
         this.wasReadFromDiff = wasReadFromDiff;
+        this.projectsSettings = projectsSettings;
         this.routingNodes = routingNodes;
         assert assertConsistentRoutingNodes(routingTable, nodes, routingNodes);
         assert assertConsistentProjectState(routingTable, metadata);
@@ -404,6 +410,14 @@ public RoutingTable routingTable(ProjectId projectId) {
         return routingTable.routingTable(projectId);
     }
 
+    public Settings projectSettings(ProjectId projectId) {
+        return projectsSettings.getOrDefault(projectId, Settings.EMPTY);
+    }
+
+    public Map<ProjectId, Settings> projectsSettings() {
+        return projectsSettings;
+    }
+
     @Deprecated(forRemoval = true)
     public RoutingTable routingTable() {
         return routingTable.getRoutingTable();
@@ -672,7 +686,8 @@ public enum Metric {
         METADATA("metadata"),
         ROUTING_TABLE("routing_table"),
         ROUTING_NODES("routing_nodes"),
-        CUSTOMS("customs");
+        CUSTOMS("customs"),
+        PROJECTS_SETTINGS("projects_settings");
 
         private static final Map<String, Metric> valueToEnum;
 
@@ -849,7 +864,22 @@ public Iterator<? extends ToXContent> toXContentChunked(ToXContent.Params outerP
                     customs.entrySet().iterator(),
                     e -> ChunkedToXContentHelper.object(e.getKey(), e.getValue().toXContentChunked(outerParams))
                 )
-                : Collections.emptyIterator()
+                : Collections.emptyIterator(),
+
+            chunkedSection(
+                multiProject && metrics.contains(Metric.PROJECTS_SETTINGS),
+                (builder, params) -> builder.startArray("projects_settings"),
+                projectsSettings.entrySet().iterator(),
+
+                entry -> Iterators.single((builder, params) -> {
+                    builder.startObject();
+                    builder.field("id", entry.getKey());
+                    builder.startObject("settings");
+                    entry.getValue().toXContent(builder, new ToXContent.MapParams(Collections.singletonMap("flat_settings", "true")));
+                    return builder.endObject().endObject();
+                }),
+                (builder, params) -> builder.endArray()
+            )
         );
     }
 
@@ -1006,6 +1036,7 @@ public static class Builder {
         private final Map<String, Set<String>> nodeFeatures;
         private ClusterBlocks blocks = ClusterBlocks.EMPTY_CLUSTER_BLOCK;
         private final ImmutableOpenMap.Builder<String, Custom> customs;
+        private final ImmutableOpenMap.Builder<ProjectId, Settings> projectsSettings;
         private boolean fromDiff;
 
         public Builder(ClusterState state) {
@@ -1021,11 +1052,13 @@ public Builder(ClusterState state) {
             this.blocks = state.blocks();
             this.customs = ImmutableOpenMap.builder(state.customs());
             this.fromDiff = false;
+            this.projectsSettings = ImmutableOpenMap.builder(state.projectsSettings);
         }
 
         public Builder(ClusterName clusterName) {
             this.compatibilityVersions = new HashMap<>();
             this.nodeFeatures = new HashMap<>();
+            this.projectsSettings = ImmutableOpenMap.builder();
             customs = ImmutableOpenMap.builder();
             this.clusterName = clusterName;
         }
@@ -1130,6 +1163,16 @@ public Builder putRoutingTable(ProjectId projectId, RoutingTable routingTable) {
             return routingTable(globalRoutingTableBuilder.put(projectId, routingTable).build());
         }
 
+        public Builder putProjectSettings(ProjectId projectId, Settings settings) {
+            projectsSettings.put(projectId, settings);
+            return this;
+        }
+
+        public Builder projectsSettings(Map<ProjectId, Settings> projectsSettings) {
+            this.projectsSettings.putAllFromMap(projectsSettings);
+            return this;
+        }
+
         public Builder metadata(Metadata.Builder metadataBuilder) {
             return metadata(metadataBuilder.build());
         }
@@ -1234,6 +1277,7 @@ public ClusterState build() {
                 metadata != null ? blocks.initializeProjects(metadata.projects().keySet()) : blocks,
                 customs.build(),
                 fromDiff,
+                projectsSettings.build(),
                 routingNodes
             );
         }
@@ -1285,6 +1329,9 @@ public static ClusterState readFrom(StreamInput in, DiscoveryNode localNode) thr
             Custom customIndexMetadata = in.readNamedWriteable(Custom.class);
             builder.putCustom(customIndexMetadata.getWriteableName(), customIndexMetadata);
         }
+        if (in.getTransportVersion().onOrAfter(TransportVersions.CLUSTER_STATE_PROJECTS_SETTINGS)) {
+            builder.projectsSettings(in.readMap(ProjectId::readFrom, Settings::readSettingsFromStream));
+        }
         return builder.build();
     }
 
@@ -1306,9 +1353,24 @@ public void writeTo(StreamOutput out) throws IOException {
         clusterFeatures.writeTo(out);
         blocks.writeTo(out);
         VersionedNamedWriteable.writeVersionedWritables(out, customs);
+        if (out.getTransportVersion().onOrAfter(TransportVersions.CLUSTER_STATE_PROJECTS_SETTINGS)) {
+            out.writeMap(projectsSettings);
+        }
     }
 
     private static class ClusterStateDiff implements Diff<ClusterState> {
+        private static final DiffableUtils.ValueSerializer<ProjectId, Settings> SETTINGS_SERIALIZER =
+            new DiffableUtils.DiffableValueSerializer<>() {
+                @Override
+                public Settings read(StreamInput in, ProjectId key) throws IOException {
+                    return Settings.readSettingsFromStream(in);
+                }
+
+                @Override
+                public Diff<Settings> readDiff(StreamInput in, ProjectId key) throws IOException {
+                    return Settings.readSettingsDiffFromStream(in);
+                }
+            };
 
         private final long toVersion;
 
@@ -1331,6 +1393,8 @@ private static class ClusterStateDiff implements Diff<ClusterState> {
 
         private final Diff<Map<String, Custom>> customs;
 
+        private final DiffableUtils.MapDiff<ProjectId, Settings, Map<ProjectId, Settings>> projectsSettings;
+
         ClusterStateDiff(ClusterState before, ClusterState after) {
             fromUuid = before.stateUUID;
             toUuid = after.stateUUID;
@@ -1348,6 +1412,12 @@ private static class ClusterStateDiff implements Diff<ClusterState> {
             metadata = after.metadata.diff(before.metadata);
             blocks = after.blocks.diff(before.blocks);
             customs = DiffableUtils.diff(before.customs, after.customs, DiffableUtils.getStringKeySerializer(), CUSTOM_VALUE_SERIALIZER);
+            projectsSettings = DiffableUtils.diff(
+                before.projectsSettings,
+                after.projectsSettings,
+                ProjectId.PROJECT_ID_SERIALIZER,
+                SETTINGS_SERIALIZER
+            );
         }
 
         ClusterStateDiff(StreamInput in, DiscoveryNode localNode) throws IOException {
@@ -1364,6 +1434,11 @@ private static class ClusterStateDiff implements Diff<ClusterState> {
             metadata = Metadata.readDiffFrom(in);
             blocks = ClusterBlocks.readDiffFrom(in);
             customs = DiffableUtils.readJdkMapDiff(in, DiffableUtils.getStringKeySerializer(), CUSTOM_VALUE_SERIALIZER);
+            if (in.getTransportVersion().onOrAfter(TransportVersions.CLUSTER_STATE_PROJECTS_SETTINGS)) {
+                projectsSettings = DiffableUtils.readJdkMapDiff(in, ProjectId.PROJECT_ID_SERIALIZER, SETTINGS_SERIALIZER);
+            } else {
+                projectsSettings = DiffableUtils.emptyDiff();
+            }
         }
 
         @Override
@@ -1380,6 +1455,9 @@ public void writeTo(StreamOutput out) throws IOException {
             metadata.writeTo(out);
             blocks.writeTo(out);
             customs.writeTo(out);
+            if (out.getTransportVersion().onOrAfter(TransportVersions.CLUSTER_STATE_PROJECTS_SETTINGS)) {
+                projectsSettings.writeTo(out);
+            }
         }
 
         @Override
@@ -1401,6 +1479,7 @@ public ClusterState apply(ClusterState state) {
             builder.metadata(metadata.apply(state.metadata));
             builder.blocks(blocks.apply(state.blocks));
             builder.customs(customs.apply(state.customs));
+            builder.projectsSettings(this.projectsSettings.apply(state.projectsSettings));
             builder.fromDiff(state);
             return builder.build();
         }

server/src/main/java/org/elasticsearch/cluster/ProjectState.java

@@ -14,6 +14,7 @@
 import org.elasticsearch.cluster.metadata.ProjectMetadata;
 import org.elasticsearch.cluster.routing.RoutingTable;
 import org.elasticsearch.common.Strings;
+import org.elasticsearch.common.settings.Settings;
 
 import java.util.Objects;
 import java.util.function.Consumer;
@@ -26,6 +27,7 @@ public final class ProjectState {
     private final ClusterState cluster;
     private final ProjectId project;
     private final ProjectMetadata projectMetadata;
+    private final Settings projectSettings;
     private final RoutingTable routingTable;
 
     ProjectState(ClusterState clusterState, ProjectId projectId) {
@@ -34,6 +36,7 @@ public final class ProjectState {
         this.cluster = clusterState;
         this.project = projectId;
         this.projectMetadata = clusterState.metadata().getProject(projectId);
+        this.projectSettings = clusterState.projectSettings(projectId);
         this.routingTable = clusterState.routingTable(projectId);
     }
 
@@ -57,6 +60,10 @@ public ClusterBlocks blocks() {
         return cluster().blocks();
     }
 
+    public Settings settings() {
+        return projectSettings;
+    }
+
     @Override
     public boolean equals(Object obj) {
         if (obj == this) return true;

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

@@ -801,10 +801,6 @@ private Iterator<? extends ToXContent> toXContentChunkedWithSingleProjectFormat(
         );
     }
 
-    private static final DiffableUtils.KeySerializer<ProjectId> PROJECT_ID_SERIALIZER = DiffableUtils.getWriteableKeySerializer(
-        ProjectId.READER
-    );
-
     private static class MetadataDiff implements Diff<Metadata> {
 
         private final long version;
@@ -846,7 +842,7 @@ private static class MetadataDiff implements Diff<Metadata> {
                 multiProject = null;
             } else {
                 singleProject = null;
-                multiProject = DiffableUtils.diff(before.projectMetadata, after.projectMetadata, PROJECT_ID_SERIALIZER);
+                multiProject = DiffableUtils.diff(before.projectMetadata, after.projectMetadata, ProjectId.PROJECT_ID_SERIALIZER);
             }
 
             if (empty) {
@@ -951,13 +947,7 @@ private MetadataDiff(StreamInput in) throws IOException {
                     RESERVED_DIFF_VALUE_READER
                 );
 
-                singleProject = new ProjectMetadata.ProjectMetadataDiff(
-                    indices,
-                    templates,
-                    projectCustoms,
-                    DiffableUtils.emptyDiff(),
-                    Settings.EMPTY_DIFF
-                );
+                singleProject = new ProjectMetadata.ProjectMetadataDiff(indices, templates, projectCustoms, DiffableUtils.emptyDiff());
                 multiProject = null;
             } else {
                 fromNodeBeforeMultiProjectsSupport = false;
@@ -1001,7 +991,7 @@ private static MapDiff<ProjectId, ProjectMetadata, Map<ProjectId, ProjectMetadat
         ) throws IOException {
             final var multiProject = DiffableUtils.readJdkMapDiff(
                 in,
-                PROJECT_ID_SERIALIZER,
+                ProjectId.PROJECT_ID_SERIALIZER,
                 ProjectMetadata::readFrom,
                 ProjectMetadata.ProjectMetadataDiff::new
             );
@@ -1075,7 +1065,7 @@ public void writeTo(StreamOutput out) throws IOException {
             } else {
                 final var multiProjectToWrite = multiProject != null
                     ? multiProject
-                    : DiffableUtils.singleEntryDiff(DEFAULT_PROJECT_ID, singleProject, PROJECT_ID_SERIALIZER);
+                    : DiffableUtils.singleEntryDiff(DEFAULT_PROJECT_ID, singleProject, ProjectId.PROJECT_ID_SERIALIZER);
 
                 if (out.getTransportVersion().before(TransportVersions.REPOSITORIES_METADATA_AS_PROJECT_CUSTOM)) {
                     writeDiffWithRepositoriesMetadataAsClusterCustom(out, clusterCustoms, multiProjectToWrite, reservedStateMetadata);

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

@@ -9,6 +9,7 @@
 
 package org.elasticsearch.cluster.metadata;
 
+import org.elasticsearch.cluster.DiffableUtils;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
@@ -26,6 +27,9 @@ public class ProjectId implements Writeable, ToXContent {
     private static final String DEFAULT_STRING = "default";
     public static final ProjectId DEFAULT = new ProjectId(DEFAULT_STRING);
     public static final Reader<ProjectId> READER = ProjectId::readFrom;
+    public static final DiffableUtils.KeySerializer<ProjectId> PROJECT_ID_SERIALIZER = DiffableUtils.getWriteableKeySerializer(
+        ProjectId.READER
+    );
     private static final int MAX_LENGTH = 128;
 
     private final String id;