HLRC: ML Adding get datafeed stats API

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

@@ -38,6 +38,7 @@
 import org.elasticsearch.client.ml.GetCalendarsRequest;
 import org.elasticsearch.client.ml.GetCategoriesRequest;
 import org.elasticsearch.client.ml.GetDatafeedRequest;
+import org.elasticsearch.client.ml.GetDatafeedStatsRequest;
 import org.elasticsearch.client.ml.GetInfluencersRequest;
 import org.elasticsearch.client.ml.GetJobRequest;
 import org.elasticsearch.client.ml.GetJobStatsRequest;
@@ -259,6 +260,23 @@ static Request stopDatafeed(StopDatafeedRequest stopDatafeedRequest) throws IOEx
         return request;
     }
 
+    static Request getDatafeedStats(GetDatafeedStatsRequest getDatafeedStatsRequest) {
+        String endpoint = new EndpointBuilder()
+            .addPathPartAsIs("_xpack")
+            .addPathPartAsIs("ml")
+            .addPathPartAsIs("datafeeds")
+            .addPathPart(Strings.collectionToCommaDelimitedString(getDatafeedStatsRequest.getDatafeedIds()))
+            .addPathPartAsIs("_stats")
+            .build();
+        Request request = new Request(HttpGet.METHOD_NAME, endpoint);
+
+        RequestConverters.Params params = new RequestConverters.Params(request);
+        if (getDatafeedStatsRequest.isAllowNoDatafeeds() != null) {
+            params.putParam("allow_no_datafeeds", Boolean.toString(getDatafeedStatsRequest.isAllowNoDatafeeds()));
+        }
+        return request;
+    }
+
     static Request deleteForecast(DeleteForecastRequest deleteForecastRequest) {
         String endpoint = new EndpointBuilder()
             .addPathPartAsIs("_xpack")

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

@@ -38,6 +38,8 @@
 import org.elasticsearch.client.ml.GetCategoriesResponse;
 import org.elasticsearch.client.ml.GetDatafeedRequest;
 import org.elasticsearch.client.ml.GetDatafeedResponse;
+import org.elasticsearch.client.ml.GetDatafeedStatsRequest;
+import org.elasticsearch.client.ml.GetDatafeedStatsResponse;
 import org.elasticsearch.client.ml.GetInfluencersRequest;
 import org.elasticsearch.client.ml.GetInfluencersResponse;
 import org.elasticsearch.client.ml.GetJobRequest;
@@ -181,7 +183,7 @@ public GetJobStatsResponse getJobStats(GetJobStatsRequest request, RequestOption
     }
 
     /**
-     * Gets one or more Machine Learning job configuration info, asynchronously.
+     * Gets usage statistics for one or more Machine Learning jobs, asynchronously.
      * <p>
      * For additional info
      * see <a href="https://www.elastic.co/guide/en/elasticsearch/reference/current/ml-get-job-stats.html">Get job stats docs</a>
@@ -649,6 +651,47 @@ public void stopDatafeedAsync(StopDatafeedRequest request, RequestOptions option
             Collections.emptySet());
     }
 
+    /**
+     * Gets statistics for one or more Machine Learning datafeeds
+     * <p>
+     * For additional info
+     * see <a href="https://www.elastic.co/guide/en/elasticsearch/reference/current/ml-get-datafeed-stats.html">Get datafeed stats docs</a>
+     *
+     * @param request {@link GetDatafeedStatsRequest} Request containing a list of datafeedId(s) and additional options
+     * @param options Additional request options (e.g. headers), use {@link RequestOptions#DEFAULT} if nothing needs to be customized
+     * @return {@link GetDatafeedStatsResponse} response object containing
+     * the {@link org.elasticsearch.client.ml.datafeed.DatafeedStats} objects and the number of datafeeds found
+     * @throws IOException when there is a serialization issue sending the request or receiving the response
+     */
+    public GetDatafeedStatsResponse getDatafeedStats(GetDatafeedStatsRequest request, RequestOptions options) throws IOException {
+        return restHighLevelClient.performRequestAndParseEntity(request,
+            MLRequestConverters::getDatafeedStats,
+            options,
+            GetDatafeedStatsResponse::fromXContent,
+            Collections.emptySet());
+    }
+
+    /**
+     * Gets statistics for one or more Machine Learning datafeeds, asynchronously.
+     * <p>
+     * For additional info
+     * see <a href="https://www.elastic.co/guide/en/elasticsearch/reference/current/ml-get-datafeed-stats.html">Get datafeed stats docs</a>
+     *
+     * @param request  {@link GetDatafeedStatsRequest} Request containing a list of datafeedId(s) and additional options
+     * @param options  Additional request options (e.g. headers), use {@link RequestOptions#DEFAULT} if nothing needs to be customized
+     * @param listener Listener to be notified with {@link GetDatafeedStatsResponse} upon request completion
+     */
+    public void getDatafeedStatsAsync(GetDatafeedStatsRequest request,
+                                      RequestOptions options,
+                                      ActionListener<GetDatafeedStatsResponse> listener) {
+        restHighLevelClient.performRequestAsyncAndParseEntity(request,
+            MLRequestConverters::getDatafeedStats,
+            options,
+            GetDatafeedStatsResponse::fromXContent,
+            listener,
+            Collections.emptySet());
+    }
+
     /**
      * Updates a Machine Learning {@link org.elasticsearch.client.ml.job.config.Job}
      * <p>

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

@@ -0,0 +1,147 @@
+/*
+ * 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.ml;
+
+import org.elasticsearch.action.ActionRequest;
+import org.elasticsearch.action.ActionRequestValidationException;
+import org.elasticsearch.client.ml.datafeed.DatafeedConfig;
+import org.elasticsearch.common.ParseField;
+import org.elasticsearch.common.Strings;
+import org.elasticsearch.common.xcontent.ConstructingObjectParser;
+import org.elasticsearch.common.xcontent.ObjectParser;
+import org.elasticsearch.common.xcontent.ToXContent;
+import org.elasticsearch.common.xcontent.ToXContentObject;
+import org.elasticsearch.common.xcontent.XContentBuilder;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * Request object to get {@link org.elasticsearch.client.ml.datafeed.DatafeedStats} by their respective datafeedIds
+ *
+ * {@code _all} explicitly gets all the datafeeds' statistics in the cluster
+ * An empty request (no {@code datafeedId}s) implicitly gets all the datafeeds' statistics in the cluster
+ */
+public class GetDatafeedStatsRequest extends ActionRequest implements ToXContentObject {
+
+    public static final ParseField ALLOW_NO_DATAFEEDS = new ParseField("allow_no_datafeeds");
+
+    @SuppressWarnings("unchecked")
+    public static final ConstructingObjectParser<GetDatafeedStatsRequest, Void> PARSER = new ConstructingObjectParser<>(
+        "get_datafeed_stats_request", a -> new GetDatafeedStatsRequest((List<String>) a[0]));
+
+    static {
+        PARSER.declareField(ConstructingObjectParser.constructorArg(),
+            p -> Arrays.asList(Strings.commaDelimitedListToStringArray(p.text())),
+            DatafeedConfig.ID, ObjectParser.ValueType.STRING_ARRAY);
+        PARSER.declareBoolean(GetDatafeedStatsRequest::setAllowNoDatafeeds, ALLOW_NO_DATAFEEDS);
+    }
+
+    private static final String ALL_DATAFEEDS = "_all";
+
+    private final List<String> datafeedIds;
+    private Boolean allowNoDatafeeds;
+
+    /**
+     * Explicitly gets all datafeeds statistics
+     *
+     * @return a {@link GetDatafeedStatsRequest} for all existing datafeeds
+     */
+    public static GetDatafeedStatsRequest getAllDatafeedStatsRequest(){
+        return new GetDatafeedStatsRequest(ALL_DATAFEEDS);
+    }
+
+    GetDatafeedStatsRequest(List<String> datafeedIds) {
+        if (datafeedIds.stream().anyMatch(Objects::isNull)) {
+            throw new NullPointerException("datafeedIds must not contain null values");
+        }
+        this.datafeedIds = new ArrayList<>(datafeedIds);
+    }
+
+    /**
+     * Get the specified Datafeed's statistics via their unique datafeedIds
+     *
+     * @param datafeedIds must be non-null and each datafeedId must be non-null
+     */
+    public GetDatafeedStatsRequest(String... datafeedIds) {
+        this(Arrays.asList(datafeedIds));
+    }
+
+    /**
+     * All the datafeedIds for which to get statistics
+     */
+    public List<String> getDatafeedIds() {
+        return datafeedIds;
+    }
+
+    public Boolean isAllowNoDatafeeds() {
+        return this.allowNoDatafeeds;
+    }
+
+    /**
+     * Whether to ignore if a wildcard expression matches no datafeeds.
+     *
+     * This includes {@code _all} string or when no datafeeds have been specified
+     *
+     * @param allowNoDatafeeds When {@code true} ignore if wildcard or {@code _all} matches no datafeeds. Defaults to {@code true}
+     */
+    public void setAllowNoDatafeeds(boolean allowNoDatafeeds) {
+        this.allowNoDatafeeds = allowNoDatafeeds;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(datafeedIds, allowNoDatafeeds);
+    }
+
+    @Override
+    public boolean equals(Object other) {
+        if (this == other) {
+            return true;
+        }
+
+        if (other == null || getClass() != other.getClass()) {
+            return false;
+        }
+
+        GetDatafeedStatsRequest that = (GetDatafeedStatsRequest) other;
+        return Objects.equals(datafeedIds, that.datafeedIds) &&
+            Objects.equals(allowNoDatafeeds, that.allowNoDatafeeds);
+    }
+
+    @Override
+    public ActionRequestValidationException validate() {
+        return null;
+    }
+
+    @Override
+    public XContentBuilder toXContent(XContentBuilder builder, ToXContent.Params params) throws IOException {
+        builder.startObject();
+        builder.field(DatafeedConfig.ID.getPreferredName(), Strings.collectionToCommaDelimitedString(datafeedIds));
+        if (allowNoDatafeeds != null) {
+            builder.field(ALLOW_NO_DATAFEEDS.getPreferredName(), allowNoDatafeeds);
+        }
+        builder.endObject();
+        return builder;
+    }
+
+}

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

@@ -0,0 +1,89 @@
+/*
+ * 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.ml;
+
+import org.elasticsearch.client.ml.datafeed.DatafeedStats;
+import org.elasticsearch.common.ParseField;
+import org.elasticsearch.common.Strings;
+import org.elasticsearch.common.xcontent.ConstructingObjectParser;
+import org.elasticsearch.common.xcontent.XContentParser;
+
+import java.io.IOException;
+import java.util.List;
+import java.util.Objects;
+
+import static org.elasticsearch.common.xcontent.ConstructingObjectParser.constructorArg;
+
+/**
+ * Contains a {@link List} of the found {@link DatafeedStats} objects and the total count found
+ */
+public class GetDatafeedStatsResponse extends AbstractResultResponse<DatafeedStats> {
+
+    public static final ParseField RESULTS_FIELD = new ParseField("datafeeds");
+
+    @SuppressWarnings("unchecked")
+    public static final ConstructingObjectParser<GetDatafeedStatsResponse, Void> PARSER =
+        new ConstructingObjectParser<>("get_datafeed_stats_response",
+            true,
+            a -> new GetDatafeedStatsResponse((List<DatafeedStats>) a[0], (long) a[1]));
+
+    static {
+        PARSER.declareObjectArray(constructorArg(), DatafeedStats.PARSER, RESULTS_FIELD);
+        PARSER.declareLong(constructorArg(), COUNT);
+    }
+
+    GetDatafeedStatsResponse(List<DatafeedStats> results, long count) {
+        super(RESULTS_FIELD, results, count);
+    }
+
+    /**
+     * The collection of {@link DatafeedStats} objects found in the query
+     */
+    public List<DatafeedStats> datafeedStats() {
+        return results;
+    }
+
+    public static GetDatafeedStatsResponse fromXContent(XContentParser parser) throws IOException {
+        return PARSER.parse(parser, null);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(results, count);
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+
+        if (obj == null || getClass() != obj.getClass()) {
+            return false;
+        }
+
+        GetDatafeedStatsResponse other = (GetDatafeedStatsResponse) obj;
+        return Objects.equals(results, other.results) && count == other.count;
+    }
+
+    @Override
+    public final String toString() {
+        return Strings.toString(this);
+    }
+}

client/rest-high-level/src/main/java/org/elasticsearch/client/ml/datafeed/DatafeedState.java

@@ -0,0 +1,42 @@
+/*
+ * 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.ml.datafeed;
+
+import org.elasticsearch.common.ParseField;
+
+import java.util.Locale;
+
+/**
+ * Datafeed State POJO
+ */
+public enum DatafeedState {
+
+    STARTED, STOPPED, STARTING, STOPPING;
+
+    public static final ParseField STATE = new ParseField("state");
+
+    public static DatafeedState fromString(String name) {
+        return valueOf(name.trim().toUpperCase(Locale.ROOT));
+    }
+
+    @Override
+    public String toString() {
+        return name().toLowerCase(Locale.ROOT);
+    }
+}