Expose SLM policy stats in get SLM policy API

client/rest-high-level/src/main/java/org/elasticsearch/client/IndexLifecycleClient.java

@@ -39,6 +39,8 @@
 import org.elasticsearch.client.slm.ExecuteSnapshotLifecyclePolicyResponse;
 import org.elasticsearch.client.slm.GetSnapshotLifecyclePolicyRequest;
 import org.elasticsearch.client.slm.GetSnapshotLifecyclePolicyResponse;
+import org.elasticsearch.client.slm.GetSnapshotLifecycleStatsRequest;
+import org.elasticsearch.client.slm.GetSnapshotLifecycleStatsResponse;
 import org.elasticsearch.client.slm.PutSnapshotLifecyclePolicyRequest;
 
 import java.io.IOException;
@@ -464,4 +466,40 @@ public Cancellable executeSnapshotLifecyclePolicyAsync(
             request, IndexLifecycleRequestConverters::executeSnapshotLifecyclePolicy,
             options, ExecuteSnapshotLifecyclePolicyResponse::fromXContent, listener, emptySet());
     }
+
+    /**
+     * Retrieve snapshot lifecycle statistics.
+     * See <pre>
+     *  https://www.elastic.co/guide/en/elasticsearch/client/java-rest/current/
+     *  java-rest-high-ilm-slm-get-snapshot-lifecycle-stats.html
+     * </pre>
+     * for more.
+     * @param request the request
+     * @param options the request options (e.g. headers), use {@link RequestOptions#DEFAULT} if nothing needs to be customized
+     * @return the response
+     * @throws IOException in case there is a problem sending the request or parsing back the response
+     */
+    public GetSnapshotLifecycleStatsResponse getSnapshotLifecycleStats(GetSnapshotLifecycleStatsRequest request,
+                                                                       RequestOptions options) throws IOException {
+        return restHighLevelClient.performRequestAndParseEntity(request, IndexLifecycleRequestConverters::getSnapshotLifecycleStats,
+            options, GetSnapshotLifecycleStatsResponse::fromXContent, emptySet());
+    }
+
+    /**
+     * Asynchronously retrieve snapshot lifecycle statistics.
+     * See <pre>
+     *  https://www.elastic.co/guide/en/elasticsearch/client/java-rest/current/
+     *  java-rest-high-ilm-slm-get-snapshot-lifecycle-stats.html
+     * </pre>
+     * for more.
+     * @param request the request
+     * @param options the request options (e.g. headers), use {@link RequestOptions#DEFAULT} if nothing needs to be customized
+     * @param listener the listener to be notified upon request completion
+     * @return cancellable that may be used to cancel the request
+     */
+    public Cancellable getSnapshotLifecycleStatsAsync(GetSnapshotLifecycleStatsRequest request, RequestOptions options,
+                                                      ActionListener<GetSnapshotLifecycleStatsResponse> listener) {
+        return restHighLevelClient.performRequestAsyncAndParseEntity(request, IndexLifecycleRequestConverters::getSnapshotLifecycleStats,
+            options, GetSnapshotLifecycleStatsResponse::fromXContent, listener, emptySet());
+    }
 }

client/rest-high-level/src/main/java/org/elasticsearch/client/IndexLifecycleRequestConverters.java

@@ -35,6 +35,7 @@
 import org.elasticsearch.client.slm.DeleteSnapshotLifecyclePolicyRequest;
 import org.elasticsearch.client.slm.ExecuteSnapshotLifecyclePolicyRequest;
 import org.elasticsearch.client.slm.GetSnapshotLifecyclePolicyRequest;
+import org.elasticsearch.client.slm.GetSnapshotLifecycleStatsRequest;
 import org.elasticsearch.client.slm.PutSnapshotLifecyclePolicyRequest;
 import org.elasticsearch.common.Strings;
 
@@ -215,4 +216,14 @@ static Request executeSnapshotLifecyclePolicy(ExecuteSnapshotLifecyclePolicyRequ
         request.addParameters(params.asMap());
         return request;
     }
+
+    static Request getSnapshotLifecycleStats(GetSnapshotLifecycleStatsRequest getSnapshotLifecycleStatsRequest) {
+        String endpoint = new RequestConverters.EndpointBuilder().addPathPartAsIs("_slm/stats").build();
+        Request request = new Request(HttpGet.METHOD_NAME, endpoint);
+        RequestConverters.Params params = new RequestConverters.Params();
+        params.withMasterTimeout(getSnapshotLifecycleStatsRequest.masterNodeTimeout());
+        params.withTimeout(getSnapshotLifecycleStatsRequest.timeout());
+        request.addParameters(params.asMap());
+        return request;
+    }
 }

client/rest-high-level/src/main/java/org/elasticsearch/client/slm/GetSnapshotLifecycleStatsRequest.java

@@ -0,0 +1,30 @@
+/*
+ * Licensed to Elasticsearch under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.elasticsearch.client.slm;
+
+import org.elasticsearch.client.TimedRequest;
+
+public class GetSnapshotLifecycleStatsRequest extends TimedRequest {
+
+    public GetSnapshotLifecycleStatsRequest() {
+        super();
+    }
+
+}

client/rest-high-level/src/main/java/org/elasticsearch/client/slm/GetSnapshotLifecycleStatsResponse.java

@@ -0,0 +1,68 @@
+/*
+ * Licensed to Elasticsearch under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.elasticsearch.client.slm;
+
+import org.elasticsearch.common.xcontent.ToXContentObject;
+import org.elasticsearch.common.xcontent.XContentBuilder;
+import org.elasticsearch.common.xcontent.XContentParser;
+
+import java.io.IOException;
+import java.util.Objects;
+
+public class GetSnapshotLifecycleStatsResponse implements ToXContentObject {
+
+    private final SnapshotLifecycleStats stats;
+
+    public GetSnapshotLifecycleStatsResponse(SnapshotLifecycleStats stats) {
+        this.stats = stats;
+    }
+
+    public SnapshotLifecycleStats getStats() {
+        return this.stats;
+    }
+
+    public static GetSnapshotLifecycleStatsResponse fromXContent(XContentParser parser) throws IOException {
+        return new GetSnapshotLifecycleStatsResponse(SnapshotLifecycleStats.parse(parser));
+    }
+
+    @Override
+    public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
+        return stats.toXContent(builder, params);
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+
+        GetSnapshotLifecycleStatsResponse other = (GetSnapshotLifecycleStatsResponse) o;
+        return Objects.equals(this.stats, other.stats);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(this.stats);
+    }
+}

client/rest-high-level/src/main/java/org/elasticsearch/client/slm/SnapshotLifecyclePolicyMetadata.java

@@ -42,6 +42,7 @@ public class SnapshotLifecyclePolicyMetadata implements ToXContentObject {
     static final ParseField NEXT_EXECUTION_MILLIS = new ParseField("next_execution_millis");
     static final ParseField NEXT_EXECUTION = new ParseField("next_execution");
     static final ParseField SNAPSHOT_IN_PROGRESS = new ParseField("in_progress");
+    static final ParseField POLICY_STATS = new ParseField("stats");
 
     private final SnapshotLifecyclePolicy policy;
     private final long version;
@@ -53,6 +54,7 @@ public class SnapshotLifecyclePolicyMetadata implements ToXContentObject {
     private final SnapshotInvocationRecord lastFailure;
     @Nullable
     private final SnapshotInProgress snapshotInProgress;
+    private final SnapshotLifecycleStats.SnapshotPolicyStats policyStats;
 
     @SuppressWarnings("unchecked")
     public static final ConstructingObjectParser<SnapshotLifecyclePolicyMetadata, String> PARSER =
@@ -65,8 +67,9 @@ public class SnapshotLifecyclePolicyMetadata implements ToXContentObject {
                 SnapshotInvocationRecord lastFailure = (SnapshotInvocationRecord) a[4];
                 long nextExecution = (long) a[5];
                 SnapshotInProgress sip = (SnapshotInProgress) a[6];
-
-                return new SnapshotLifecyclePolicyMetadata(policy, version, modifiedDate, lastSuccess, lastFailure, nextExecution, sip);
+                SnapshotLifecycleStats.SnapshotPolicyStats stats = (SnapshotLifecycleStats.SnapshotPolicyStats) a[7];
+                return new SnapshotLifecyclePolicyMetadata(policy, version, modifiedDate, lastSuccess,
+                    lastFailure, nextExecution, sip, stats);
             });
 
     static {
@@ -77,6 +80,9 @@ public class SnapshotLifecyclePolicyMetadata implements ToXContentObject {
         PARSER.declareObject(ConstructingObjectParser.optionalConstructorArg(), SnapshotInvocationRecord::parse, LAST_FAILURE);
         PARSER.declareLong(ConstructingObjectParser.constructorArg(), NEXT_EXECUTION_MILLIS);
         PARSER.declareObject(ConstructingObjectParser.optionalConstructorArg(), SnapshotInProgress::parse, SNAPSHOT_IN_PROGRESS);
+        PARSER.declareObject(ConstructingObjectParser.constructorArg(),
+            (p, c) -> SnapshotLifecycleStats.SnapshotPolicyStats.parse(p, "policy"), POLICY_STATS);
+
     }
 
     public static SnapshotLifecyclePolicyMetadata parse(XContentParser parser, String id) {
@@ -86,14 +92,16 @@ public static SnapshotLifecyclePolicyMetadata parse(XContentParser parser, Strin
     public SnapshotLifecyclePolicyMetadata(SnapshotLifecyclePolicy policy, long version, long modifiedDate,
                                            SnapshotInvocationRecord lastSuccess, SnapshotInvocationRecord lastFailure,
                                            long nextExecution,
-                                           @Nullable SnapshotInProgress snapshotInProgress) {
+                                           @Nullable SnapshotInProgress snapshotInProgress,
+                                           SnapshotLifecycleStats.SnapshotPolicyStats policyStats) {
         this.policy = policy;
         this.version = version;
         this.modifiedDate = modifiedDate;
         this.lastSuccess = lastSuccess;
         this.lastFailure = lastFailure;
         this.nextExecution = nextExecution;
         this.snapshotInProgress = snapshotInProgress;
+        this.policyStats = policyStats;
     }
 
     public SnapshotLifecyclePolicy getPolicy() {
@@ -124,6 +132,10 @@ public long getNextExecution() {
         return this.nextExecution;
     }
 
+    public SnapshotLifecycleStats.SnapshotPolicyStats getPolicyStats() {
+        return this.policyStats;
+    }
+
     @Nullable
     public SnapshotInProgress getSnapshotInProgress() {
         return this.snapshotInProgress;
@@ -145,13 +157,16 @@ public XContentBuilder toXContent(XContentBuilder builder, Params params) throws
         if (snapshotInProgress != null) {
             builder.field(SNAPSHOT_IN_PROGRESS.getPreferredName(), snapshotInProgress);
         }
+        builder.startObject(POLICY_STATS.getPreferredName());
+        this.policyStats.toXContent(builder, params);
+        builder.endObject();
         builder.endObject();
         return builder;
     }
 
     @Override
     public int hashCode() {
-        return Objects.hash(policy, version, modifiedDate, lastSuccess, lastFailure, nextExecution);
+        return Objects.hash(policy, version, modifiedDate, lastSuccess, lastFailure, nextExecution, policyStats);
     }
 
     @Override
@@ -168,7 +183,8 @@ public boolean equals(Object obj) {
             Objects.equals(modifiedDate, other.modifiedDate) &&
             Objects.equals(lastSuccess, other.lastSuccess) &&
             Objects.equals(lastFailure, other.lastFailure) &&
-            Objects.equals(nextExecution, other.nextExecution);
+            Objects.equals(nextExecution, other.nextExecution) &&
+            Objects.equals(policyStats, other.policyStats);
     }
 
     public static class SnapshotInProgress implements ToXContentObject {