[rule based autotagging] Add Get Rule API Logic

CHANGELOG.md

@@ -5,6 +5,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 ## [Unreleased 3.x]
 ### Added
+- [Rule based auto-tagging] Add get rule API ([#17336](https://github.com/opensearch-project/OpenSearch/pull/17336))
 - Add multi-threaded writer support in pull-based ingestion ([#17912](https://github.com/opensearch-project/OpenSearch/pull/17912))
 - Implement parallel shard refresh behind cluster settings ([#17782](https://github.com/opensearch-project/OpenSearch/pull/17782))
 

modules/autotagging-commons/build.gradle

@@ -0,0 +1,21 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+
+opensearchplugin {
+  description = 'OpenSearch Rule Framework plugin'
+  classname = 'org.opensearch.rule.RuleFrameworkPlugin'
+}
+
+dependencies {
+  api project("spi")
+  api project("common")
+  testImplementation(project(":test:framework")) {
+    exclude group: 'org.opensearch', module: 'opensearch-core'
+  }
+}

libs/autotagging-commons/build.gradle → modules/autotagging-commons/common/build.gradle

@@ -6,15 +6,22 @@
  * compatible open source license.
  */
 
+apply plugin: 'opensearch.build'
+apply plugin: 'opensearch.publish'
+
+description = 'OpenSearch Rule framework common constructs which spi and module shares'
+
 dependencies {
   api 'org.apache.commons:commons-collections4:4.4'
-  api project(":server")
+  implementation project(":libs:opensearch-common")
+  compileOnly project(":server")
 
   testImplementation(project(":test:framework")) {
     exclude group: 'org.opensearch', module: 'opensearch-core'
   }
 }
 
+
 tasks.named("dependencyLicenses").configure {
   mapping from: /commons-collections.*/, to: 'commons-collections'
 }

modules/autotagging-commons/common/src/main/java/org/opensearch/rule/GetRuleRequest.java

@@ -0,0 +1,116 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.rule;
+
+import org.opensearch.action.ActionRequest;
+import org.opensearch.action.ActionRequestValidationException;
+import org.opensearch.common.annotation.ExperimentalApi;
+import org.opensearch.core.common.io.stream.StreamInput;
+import org.opensearch.core.common.io.stream.StreamOutput;
+import org.opensearch.rule.autotagging.Attribute;
+import org.opensearch.rule.autotagging.FeatureType;
+import org.opensearch.rule.autotagging.Rule;
+import org.opensearch.rule.autotagging.RuleValidator;
+
+import java.io.IOException;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * A request for get Rule
+ * Example Request:
+ * The endpoint "localhost:9200/_wlm/rule" is specific to the Workload Management feature to manage rules
+ * curl -X GET "localhost:9200/_wlm/rule" - get all rules
+ * curl -X GET "localhost:9200/_wlm/rule/{_id}" - get single rule by id
+ * curl -X GET "localhost:9200/_wlm/rule?index_pattern=a,b" - get all rules containing attribute index_pattern as a or b
+ * @opensearch.experimental
+ */
+@ExperimentalApi
+public class GetRuleRequest extends ActionRequest {
+    private final String id;
+    private final Map<Attribute, Set<String>> attributeFilters;
+    private final String searchAfter;
+    private final FeatureType featureType;
+
+    /**
+     * Constructor for GetRuleRequest
+     * @param id - Rule id to get
+     * @param attributeFilters - Rules will be filtered based on the attribute-value mappings.
+     * @param searchAfter - The sort value used for pagination.
+     * @param featureType - The feature type related to rule.
+     */
+    public GetRuleRequest(String id, Map<Attribute, Set<String>> attributeFilters, String searchAfter, FeatureType featureType) {
+        this.id = id;
+        this.attributeFilters = attributeFilters;
+        this.searchAfter = searchAfter;
+        this.featureType = featureType;
+    }
+
+    /**
+     * Constructs a GetRuleRequest from a StreamInput for deserialization.
+     * @param in - The {@link StreamInput} instance to read from.
+     */
+    public GetRuleRequest(StreamInput in) throws IOException {
+        super(in);
+        id = in.readOptionalString();
+        featureType = FeatureType.from(in);
+        attributeFilters = in.readMap(i -> Attribute.from(i, featureType), i -> new HashSet<>(i.readStringList()));
+        searchAfter = in.readOptionalString();
+    }
+
+    @Override
+    public ActionRequestValidationException validate() {
+        if (RuleValidator.isEmpty(id)) {
+            throw new IllegalArgumentException(Rule._ID_STRING + " cannot be empty.");
+        }
+        if (RuleValidator.isEmpty(searchAfter)) {
+            throw new IllegalArgumentException("search_after cannot be empty.");
+        }
+        return null;
+    }
+
+    @Override
+    public void writeTo(StreamOutput out) throws IOException {
+        super.writeTo(out);
+        out.writeOptionalString(id);
+        featureType.writeTo(out);
+        out.writeMap(attributeFilters, (output, attribute) -> attribute.writeTo(output), StreamOutput::writeStringCollection);
+        out.writeOptionalString(searchAfter);
+    }
+
+    /**
+     * id getter
+     */
+    public String getId() {
+        return id;
+    }
+
+    /**
+     * attributeFilters getter
+     */
+    public Map<Attribute, Set<String>> getAttributeFilters() {
+        return attributeFilters;
+    }
+
+    /**
+     * searchAfter getter
+     */
+    public String getSearchAfter() {
+        return searchAfter;
+    }
+
+    /**
+     * FeatureType getter
+     * @return
+     */
+    public FeatureType getFeatureType() {
+        return featureType;
+    }
+}

modules/autotagging-commons/common/src/main/java/org/opensearch/rule/GetRuleResponse.java

@@ -0,0 +1,93 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.rule;
+
+import org.opensearch.common.annotation.ExperimentalApi;
+import org.opensearch.core.action.ActionResponse;
+import org.opensearch.core.common.io.stream.StreamInput;
+import org.opensearch.core.common.io.stream.StreamOutput;
+import org.opensearch.core.xcontent.ToXContent;
+import org.opensearch.core.xcontent.ToXContentObject;
+import org.opensearch.core.xcontent.XContentBuilder;
+import org.opensearch.rule.autotagging.Rule;
+
+import java.io.IOException;
+import java.util.Map;
+
+import static org.opensearch.rule.autotagging.Rule._ID_STRING;
+
+/**
+ * Response for the get API for Rule.
+ * Example response:
+ * {
+ *     "rules": [
+ *         {
+ *             "_id": "z1MJApUB0zgMcDmz-UQq",
+ *             "description": "Rule for tagging query_group_id to index123"
+ *             "index_pattern": ["index123"],
+ *             "query_group": "query_group_id",
+ *             "updated_at": "2025-02-14T01:19:22.589Z"
+ *         },
+ *         ...
+ *     ],
+ *     "search_after": ["z1MJApUB0zgMcDmz-UQq"]
+ * }
+ * @opensearch.experimental
+ */
+@ExperimentalApi
+public class GetRuleResponse extends ActionResponse implements ToXContent, ToXContentObject {
+    private final Map<String, Rule> rules;
+    private final String searchAfter;
+
+    /**
+     * Constructor for GetRuleResponse
+     * @param rules - Rules get from the request
+     * @param searchAfter - The sort value used for pagination.
+     */
+    public GetRuleResponse(final Map<String, Rule> rules, String searchAfter) {
+        this.rules = rules;
+        this.searchAfter = searchAfter;
+    }
+
+    /**
+     * Constructs a GetRuleResponse from a StreamInput for deserialization
+     * @param in - The {@link StreamInput} instance to read from.
+     */
+    public GetRuleResponse(StreamInput in) throws IOException {
+        this(in.readMap(StreamInput::readString, Rule::new), in.readOptionalString());
+    }
+
+    @Override
+    public void writeTo(StreamOutput out) throws IOException {
+        out.writeMap(rules, StreamOutput::writeString, (outStream, rule) -> rule.writeTo(outStream));
+        out.writeOptionalString(searchAfter);
+    }
+
+    @Override
+    public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
+        builder.startObject();
+        builder.startArray("rules");
+        for (Map.Entry<String, Rule> entry : rules.entrySet()) {
+            entry.getValue().toXContent(builder, new MapParams(Map.of(_ID_STRING, entry.getKey())));
+        }
+        builder.endArray();
+        if (searchAfter != null && !searchAfter.isEmpty()) {
+            builder.field("search_after", new Object[] { searchAfter });
+        }
+        builder.endObject();
+        return builder;
+    }
+
+    /**
+     * rules getter
+     */
+    public Map<String, Rule> getRules() {
+        return rules;
+    }
+}

modules/autotagging-commons/common/src/main/java/org/opensearch/rule/RuleAttribute.java

@@ -0,0 +1,47 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.rule;
+
+import org.opensearch.rule.autotagging.Attribute;
+
+/**
+ * Generic Rule attributes that features can use out of the use by using the lib.
+ * @opensearch.experimental
+ */
+public enum RuleAttribute implements Attribute {
+    /**
+     * Represents the index_pattern attribute in RuleAttribute
+     */
+    INDEX_PATTERN("index_pattern");
+
+    private final String name;
+
+    RuleAttribute(String name) {
+        this.name = name;
+        validateAttribute();
+    }
+
+    @Override
+    public String getName() {
+        return name;
+    }
+
+    /**
+     * Retrieves the RuleAttribute from a name string
+     * @param name - attribute name
+     */
+    public static RuleAttribute fromName(String name) {
+        for (RuleAttribute attr : RuleAttribute.values()) {
+            if (attr.getName().equals(name)) {
+                return attr;
+            }
+        }
+        throw new IllegalArgumentException("Unknown RuleAttribute: " + name);
+    }
+}

modules/autotagging-commons/common/src/main/java/org/opensearch/rule/RuleEntityParser.java

@@ -0,0 +1,27 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.rule;
+
+import org.opensearch.common.annotation.ExperimentalApi;
+import org.opensearch.rule.autotagging.Rule;
+
+/**
+ * Interface to parse various string representation of Rule entity
+ * clients can use/implement as per their choice of storage for the Rule
+ */
+@ExperimentalApi
+public interface RuleEntityParser {
+    /**
+     * Parses the src string into {@link Rule} object
+     * @param src String representation of Rule, it could be a XContentObject or something else based on
+     *           where and how it is stored
+     * @return Rule
+     */
+    Rule parse(String src);
+}

modules/autotagging-commons/common/src/main/java/org/opensearch/rule/RulePersistenceService.java

@@ -0,0 +1,25 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.rule;
+
+import org.opensearch.core.action.ActionListener;
+
+/**
+ * Interface for a service that handles rule persistence CRUD operations.
+ * @opensearch.experimental
+ */
+public interface RulePersistenceService {
+
+    /**
+     * Get rules based on the provided request.
+     * @param request The request containing the details for retrieving the rule.
+     * @param listener The listener that will handle the response or failure.
+     */
+    void getRule(GetRuleRequest request, ActionListener<GetRuleResponse> listener);
+}

modules/autotagging-commons/common/src/main/java/org/opensearch/rule/RuleQueryMapper.java

@@ -0,0 +1,26 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.rule;
+
+import org.opensearch.common.annotation.ExperimentalApi;
+
+/**
+ * This interface is responsible for creating query objects which storage layer can use
+ * to query the backend
+ * @param <T>
+ */
+@ExperimentalApi
+public interface RuleQueryMapper<T> {
+    /**
+     * This method translates the {@link GetRuleRequest} to a storage engine specific  query object
+     * @param request
+     * @return
+     */
+    T from(GetRuleRequest request);
+}