Remove LegacyVersion.v6.4.x constants (opensearch-project#1787)

This commit removes the `LegacyVersion.v6.4.x` constants and their usages, since we no longer need to support those in OpenSearch 2.0 onwards.

Signed-off-by: Rabi Panda <adnapibar@gmail.com>

Author: adnapibar

modules/lang-painless/src/main/java/org/opensearch/painless/action/PainlessExecuteAction.java

@@ -42,7 +42,6 @@
 import org.apache.lucene.search.ScoreMode;
 import org.apache.lucene.search.Scorer;
 import org.apache.lucene.search.Weight;
-import org.opensearch.LegacyESVersion;
 import org.apache.lucene.store.ByteBuffersDirectory;
 import org.apache.lucene.store.Directory;
 import org.opensearch.action.ActionRequestValidationException;
@@ -314,15 +313,8 @@ static Request parse(XContentParser parser) throws IOException {
         Request(StreamInput in) throws IOException {
             super(in);
             script = new Script(in);
-            if (in.getVersion().before(LegacyESVersion.V_6_4_0)) {
-                byte scriptContextId = in.readByte();
-                assert scriptContextId == 0;
-                context = null;
-                contextSetup = null;
-            } else {
-                context = fromScriptContextName(in.readString());
-                contextSetup = in.readOptionalWriteable(ContextSetup::new);
-            }
+            context = fromScriptContextName(in.readString());
+            contextSetup = in.readOptionalWriteable(ContextSetup::new);
         }
 
         public Script getScript() {
@@ -358,12 +350,8 @@ public ActionRequestValidationException validate() {
         public void writeTo(StreamOutput out) throws IOException {
             super.writeTo(out);
             script.writeTo(out);
-            if (out.getVersion().before(LegacyESVersion.V_6_4_0)) {
-                out.writeByte((byte) 0);
-            } else {
-                out.writeString(context.name);
-                out.writeOptionalWriteable(contextSetup);
-            }
+            out.writeString(context.name);
+            out.writeOptionalWriteable(contextSetup);
         }
 
         // For testing only:

qa/full-cluster-restart/src/test/java/org/opensearch/upgrades/FullClusterRestartIT.java

@@ -351,7 +351,7 @@ public void testShrink() throws IOException {
             client().performRequest(updateSettingsRequest);
 
             Request shrinkIndexRequest = new Request("PUT", "/" + index + "/_shrink/" + shrunkenIndex);
-            if (getOldClusterVersion().onOrAfter(LegacyESVersion.V_6_4_0) && getOldClusterVersion().before(LegacyESVersion.V_7_0_0)) {
+            if (getOldClusterVersion().before(LegacyESVersion.V_7_0_0)) {
                 shrinkIndexRequest.addParameter("copy_settings", "true");
             }
             shrinkIndexRequest.setJsonEntity("{\"settings\": {\"index.number_of_shards\": 1}}");

server/src/main/java/org/opensearch/LegacyESVersion.java

@@ -46,10 +46,6 @@
  */
 public class LegacyESVersion extends Version {
 
-    public static final LegacyESVersion V_6_4_0 = new LegacyESVersion(6040099, org.apache.lucene.util.Version.LUCENE_7_4_0);
-    public static final LegacyESVersion V_6_4_1 = new LegacyESVersion(6040199, org.apache.lucene.util.Version.LUCENE_7_4_0);
-    public static final LegacyESVersion V_6_4_2 = new LegacyESVersion(6040299, org.apache.lucene.util.Version.LUCENE_7_4_0);
-    public static final LegacyESVersion V_6_4_3 = new LegacyESVersion(6040399, org.apache.lucene.util.Version.LUCENE_7_4_0);
     public static final LegacyESVersion V_6_5_0 = new LegacyESVersion(6050099, org.apache.lucene.util.Version.LUCENE_7_5_0);
     public static final LegacyESVersion V_6_5_1 = new LegacyESVersion(6050199, org.apache.lucene.util.Version.LUCENE_7_5_0);
     public static final LegacyESVersion V_6_5_2 = new LegacyESVersion(6050299, org.apache.lucene.util.Version.LUCENE_7_5_0);

server/src/main/java/org/opensearch/action/admin/cluster/reroute/ClusterRerouteResponse.java

@@ -32,7 +32,6 @@
 
 package org.opensearch.action.admin.cluster.reroute;
 
-import org.opensearch.LegacyESVersion;
 import org.opensearch.action.support.master.AcknowledgedResponse;
 import org.opensearch.cluster.ClusterState;
 import org.opensearch.cluster.routing.allocation.RoutingExplanations;
@@ -53,15 +52,9 @@ public class ClusterRerouteResponse extends AcknowledgedResponse implements ToXC
     private final RoutingExplanations explanations;
 
     ClusterRerouteResponse(StreamInput in) throws IOException {
-        super(in, in.getVersion().onOrAfter(LegacyESVersion.V_6_4_0));
-        if (in.getVersion().onOrAfter(LegacyESVersion.V_6_4_0)) {
-            state = ClusterState.readFrom(in, null);
-            explanations = RoutingExplanations.readFrom(in);
-        } else {
-            state = ClusterState.readFrom(in, null);
-            acknowledged = in.readBoolean();
-            explanations = RoutingExplanations.readFrom(in);
-        }
+        super(in);
+        state = ClusterState.readFrom(in, null);
+        explanations = RoutingExplanations.readFrom(in);
     }
 
     ClusterRerouteResponse(boolean acknowledged, ClusterState state, RoutingExplanations explanations) {
@@ -83,15 +76,9 @@ public RoutingExplanations getExplanations() {
 
     @Override
     public void writeTo(StreamOutput out) throws IOException {
-        if (out.getVersion().onOrAfter(LegacyESVersion.V_6_4_0)) {
-            super.writeTo(out);
-            state.writeTo(out);
-            RoutingExplanations.writeTo(explanations, out);
-        } else {
-            state.writeTo(out);
-            out.writeBoolean(acknowledged);
-            RoutingExplanations.writeTo(explanations, out);
-        }
+        super.writeTo(out);
+        state.writeTo(out);
+        RoutingExplanations.writeTo(explanations, out);
     }
 
     @Override

server/src/main/java/org/opensearch/action/admin/cluster/settings/ClusterUpdateSettingsResponse.java

@@ -32,7 +32,6 @@
 
 package org.opensearch.action.admin.cluster.settings;
 
-import org.opensearch.LegacyESVersion;
 import org.opensearch.action.support.master.AcknowledgedResponse;
 import org.opensearch.common.ParseField;
 import org.opensearch.common.io.stream.StreamInput;
@@ -70,15 +69,9 @@ public class ClusterUpdateSettingsResponse extends AcknowledgedResponse {
     final Settings persistentSettings;
 
     ClusterUpdateSettingsResponse(StreamInput in) throws IOException {
-        super(in, in.getVersion().onOrAfter(LegacyESVersion.V_6_4_0));
-        if (in.getVersion().onOrAfter(LegacyESVersion.V_6_4_0)) {
-            transientSettings = Settings.readSettingsFromStream(in);
-            persistentSettings = Settings.readSettingsFromStream(in);
-        } else {
-            transientSettings = Settings.readSettingsFromStream(in);
-            persistentSettings = Settings.readSettingsFromStream(in);
-            acknowledged = in.readBoolean();
-        }
+        super(in);
+        transientSettings = Settings.readSettingsFromStream(in);
+        persistentSettings = Settings.readSettingsFromStream(in);
     }
 
     ClusterUpdateSettingsResponse(boolean acknowledged, Settings transientSettings, Settings persistentSettings) {
@@ -97,15 +90,9 @@ public Settings getPersistentSettings() {
 
     @Override
     public void writeTo(StreamOutput out) throws IOException {
-        if (out.getVersion().onOrAfter(LegacyESVersion.V_6_4_0)) {
-            super.writeTo(out);
-            Settings.writeSettingsToStream(transientSettings, out);
-            Settings.writeSettingsToStream(persistentSettings, out);
-        } else {
-            Settings.writeSettingsToStream(transientSettings, out);
-            Settings.writeSettingsToStream(persistentSettings, out);
-            out.writeBoolean(acknowledged);
-        }
+        super.writeTo(out);
+        Settings.writeSettingsToStream(transientSettings, out);
+        Settings.writeSettingsToStream(persistentSettings, out);
     }
 
     @Override

server/src/main/java/org/opensearch/action/admin/cluster/snapshots/status/SnapshotStats.java

@@ -32,7 +32,6 @@
 
 package org.opensearch.action.admin.cluster.snapshots.status;
 
-import org.opensearch.LegacyESVersion;
 import org.opensearch.common.Strings;
 import org.opensearch.common.io.stream.StreamInput;
 import org.opensearch.common.io.stream.StreamOutput;
@@ -70,13 +69,8 @@ public class SnapshotStats implements Writeable, ToXContentObject {
         incrementalSize = in.readVLong();
         processedSize = in.readVLong();
 
-        if (in.getVersion().onOrAfter(LegacyESVersion.V_6_4_0)) {
-            totalFileCount = in.readVInt();
-            totalSize = in.readVLong();
-        } else {
-            totalFileCount = incrementalFileCount;
-            totalSize = incrementalSize;
-        }
+        totalFileCount = in.readVInt();
+        totalSize = in.readVLong();
     }
 
     SnapshotStats(
@@ -167,10 +161,8 @@ public void writeTo(StreamOutput out) throws IOException {
         out.writeVLong(incrementalSize);
         out.writeVLong(processedSize);
 
-        if (out.getVersion().onOrAfter(LegacyESVersion.V_6_4_0)) {
-            out.writeVInt(totalFileCount);
-            out.writeVLong(totalSize);
-        }
+        out.writeVInt(totalFileCount);
+        out.writeVLong(totalSize);
     }
 
     static final class Fields {

server/src/main/java/org/opensearch/action/admin/cluster/storedscripts/GetStoredScriptResponse.java

@@ -32,7 +32,6 @@
 
 package org.opensearch.action.admin.cluster.storedscripts;
 
-import org.opensearch.LegacyESVersion;
 import org.opensearch.action.ActionResponse;
 import org.opensearch.common.ParseField;
 import org.opensearch.common.io.stream.StreamInput;
@@ -91,9 +90,7 @@ public GetStoredScriptResponse(StreamInput in) throws IOException {
             source = null;
         }
 
-        if (in.getVersion().onOrAfter(LegacyESVersion.V_6_4_0)) {
-            id = in.readString();
-        }
+        id = in.readString();
     }
 
     GetStoredScriptResponse(String id, StoredScriptSource source) {
@@ -144,9 +141,7 @@ public void writeTo(StreamOutput out) throws IOException {
             out.writeBoolean(true);
             source.writeTo(out);
         }
-        if (out.getVersion().onOrAfter(LegacyESVersion.V_6_4_0)) {
-            out.writeString(id);
-        }
+        out.writeString(id);
     }
 
     @Override

server/src/main/java/org/opensearch/action/admin/indices/alias/Alias.java

@@ -87,11 +87,7 @@ public Alias(StreamInput in) throws IOException {
         filter = in.readOptionalString();
         indexRouting = in.readOptionalString();
         searchRouting = in.readOptionalString();
-        if (in.getVersion().onOrAfter(LegacyESVersion.V_6_4_0)) {
-            writeIndex = in.readOptionalBoolean();
-        } else {
-            writeIndex = null;
-        }
+        writeIndex = in.readOptionalBoolean();
         if (in.getVersion().onOrAfter(LegacyESVersion.V_7_7_0)) {
             isHidden = in.readOptionalBoolean();
         } else {
@@ -237,9 +233,7 @@ public void writeTo(StreamOutput out) throws IOException {
         out.writeOptionalString(filter);
         out.writeOptionalString(indexRouting);
         out.writeOptionalString(searchRouting);
-        if (out.getVersion().onOrAfter(LegacyESVersion.V_6_4_0)) {
-            out.writeOptionalBoolean(writeIndex);
-        }
+        out.writeOptionalBoolean(writeIndex);
         if (out.getVersion().onOrAfter(LegacyESVersion.V_7_7_0)) {
             out.writeOptionalBoolean(isHidden);
         }

server/src/main/java/org/opensearch/action/admin/indices/alias/IndicesAliasesRequest.java

@@ -270,9 +270,7 @@ public AliasActions(StreamInput in) throws IOException {
             routing = in.readOptionalString();
             searchRouting = in.readOptionalString();
             indexRouting = in.readOptionalString();
-            if (in.getVersion().onOrAfter(LegacyESVersion.V_6_4_0)) {
-                writeIndex = in.readOptionalBoolean();
-            }
+            writeIndex = in.readOptionalBoolean();
             // TODO fix for backport of https://github.com/elastic/elasticsearch/pull/52547
             if (in.getVersion().onOrAfter(LegacyESVersion.V_7_7_0)) {
                 isHidden = in.readOptionalBoolean();
@@ -296,9 +294,7 @@ public void writeTo(StreamOutput out) throws IOException {
             out.writeOptionalString(routing);
             out.writeOptionalString(searchRouting);
             out.writeOptionalString(indexRouting);
-            if (out.getVersion().onOrAfter(LegacyESVersion.V_6_4_0)) {
-                out.writeOptionalBoolean(writeIndex);
-            }
+            out.writeOptionalBoolean(writeIndex);
             // TODO fix for backport https://github.com/elastic/elasticsearch/pull/52547
             if (out.getVersion().onOrAfter(LegacyESVersion.V_7_7_0)) {
                 out.writeOptionalBoolean(isHidden);

server/src/main/java/org/opensearch/action/admin/indices/alias/get/GetAliasesRequest.java

@@ -31,7 +31,6 @@
 
 package org.opensearch.action.admin.indices.alias.get;
 
-import org.opensearch.LegacyESVersion;
 import org.opensearch.action.ActionRequestValidationException;
 import org.opensearch.action.AliasesRequest;
 import org.opensearch.action.support.IndicesOptions;
@@ -61,9 +60,7 @@ public GetAliasesRequest(StreamInput in) throws IOException {
         indices = in.readStringArray();
         aliases = in.readStringArray();
         indicesOptions = IndicesOptions.readIndicesOptions(in);
-        if (in.getVersion().onOrAfter(LegacyESVersion.V_6_4_0)) {
-            originalAliases = in.readStringArray();
-        }
+        originalAliases = in.readStringArray();
     }
 
     @Override
@@ -72,9 +69,7 @@ public void writeTo(StreamOutput out) throws IOException {
         out.writeStringArray(indices);
         out.writeStringArray(aliases);
         indicesOptions.writeIndicesOptions(out);
-        if (out.getVersion().onOrAfter(LegacyESVersion.V_6_4_0)) {
-            out.writeStringArray(originalAliases);
-        }
+        out.writeStringArray(originalAliases);
     }
 
     @Override

server/src/main/java/org/opensearch/action/admin/indices/close/CloseIndexResponse.java

@@ -57,7 +57,7 @@ public class CloseIndexResponse extends ShardsAcknowledgedResponse {
     private final List<IndexResult> indices;
 
     CloseIndexResponse(StreamInput in) throws IOException {
-        super(in, in.getVersion().onOrAfter(LegacyESVersion.V_7_2_0), true);
+        super(in, in.getVersion().onOrAfter(LegacyESVersion.V_7_2_0));
         if (in.getVersion().onOrAfter(LegacyESVersion.V_7_3_0)) {
             indices = unmodifiableList(in.readList(IndexResult::new));
         } else {

server/src/main/java/org/opensearch/action/admin/indices/create/CreateIndexResponse.java

@@ -71,7 +71,7 @@ protected static <T extends CreateIndexResponse> void declareFields(Constructing
     private final String index;
 
     protected CreateIndexResponse(StreamInput in) throws IOException {
-        super(in, true, true);
+        super(in, true);
         index = in.readString();
     }
 

server/src/main/java/org/opensearch/action/admin/indices/get/GetIndexRequest.java

@@ -32,7 +32,6 @@
 
 package org.opensearch.action.admin.indices.get;
 
-import org.opensearch.LegacyESVersion;
 import org.opensearch.action.ActionRequestValidationException;
 import org.opensearch.action.support.master.info.ClusterInfoRequest;
 import org.opensearch.common.io.stream.StreamInput;
@@ -90,9 +89,7 @@ public GetIndexRequest(StreamInput in) throws IOException {
         super(in);
         features = in.readArray(i -> Feature.fromId(i.readByte()), Feature[]::new);
         humanReadable = in.readBoolean();
-        if (in.getVersion().onOrAfter(LegacyESVersion.V_6_4_0)) {
-            includeDefaults = in.readBoolean();
-        }
+        includeDefaults = in.readBoolean();
     }
 
     public GetIndexRequest features(Feature... features) {
@@ -156,9 +153,7 @@ public void writeTo(StreamOutput out) throws IOException {
         super.writeTo(out);
         out.writeArray((o, f) -> o.writeByte(f.id), features);
         out.writeBoolean(humanReadable);
-        if (out.getVersion().onOrAfter(LegacyESVersion.V_6_4_0)) {
-            out.writeBoolean(includeDefaults);
-        }
+        out.writeBoolean(includeDefaults);
     }
 
 }

server/src/main/java/org/opensearch/action/admin/indices/open/OpenIndexResponse.java

@@ -56,7 +56,7 @@ public class OpenIndexResponse extends ShardsAcknowledgedResponse {
     }
 
     public OpenIndexResponse(StreamInput in) throws IOException {
-        super(in, true, true);
+        super(in, true);
     }
 
     public OpenIndexResponse(boolean acknowledged, boolean shardsAcknowledged) {

server/src/main/java/org/opensearch/action/admin/indices/readonly/AddIndexBlockResponse.java

@@ -55,7 +55,7 @@ public class AddIndexBlockResponse extends ShardsAcknowledgedResponse {
     private final List<AddBlockResult> indices;
 
     AddIndexBlockResponse(StreamInput in) throws IOException {
-        super(in, true, true);
+        super(in, true);
         indices = unmodifiableList(in.readList(AddBlockResult::new));
     }