Initial search pipelines implementation

This commit includes the basic features of search pipelines
(see opensearch-project/search-processor#80).

Search pipelines are modeled after ingest pipelines and provide a
simple, clean API for components to modify search requests and
responses.

With this commit we can:

1. Can create, retrieve, update, and delete search pipelines.
2. Transform search requests and responses by explicitly referencing a
   pipeline.

Later work will include:

1. Adding an index setting to specify a default search pipeline.
2. Allowing search pipelines to be defined within a search request (for
   development/testing purposes, akin to simulating an ingest
   pipeline).
3. Adding a collection of search pipeline processors to support common
   useful transformations. (Suggestions welcome!)

Signed-off-by: Michael Froh <froh@amazon.com>

CHANGELOG.md

@@ -78,6 +78,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Disallow multiple data paths for search nodes ([#6427](https://github.com/opensearch-project/OpenSearch/pull/6427))
 - [Segment Replication] Allocation and rebalancing based on average primary shard count per index ([#6422](https://github.com/opensearch-project/OpenSearch/pull/6422))
 - Add 'base_path' setting to File System Repository ([#6558](https://github.com/opensearch-project/OpenSearch/pull/6558))
+- Add initial search pipelines ([#dummy](https://github.com/opensearch-project/OpenSearch/pull/dummy))
 
 ### Dependencies
 - Bump `org.apache.logging.log4j:log4j-core` from 2.18.0 to 2.20.0 ([#6490](https://github.com/opensearch-project/OpenSearch/pull/6490))

modules/search-pipeline-common/build.gradle

@@ -0,0 +1,68 @@
+/*
+ * 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.
+ *
+ * Modifications Copyright OpenSearch Contributors. See
+ * GitHub history for details.
+ */
+
+/*
+ * 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.
+ */
+apply plugin: 'opensearch.yaml-rest-test'
+apply plugin: 'opensearch.internal-cluster-test'
+
+opensearchplugin {
+  description 'Module for search pipeline processors that do not require additional security permissions or have large dependencies and resources'
+  classname 'org.opensearch.search.pipeline.common.SearchPipelineCommonModulePlugin'
+  extendedPlugins = ['lang-painless']
+}
+
+dependencies {
+  compileOnly project(':modules:lang-painless')
+  api project(':libs:opensearch-grok')
+  api project(':libs:opensearch-dissect')
+}
+
+restResources {
+  restApi {
+    includeCore '_common', 'search', 'cluster', 'indices', 'index', 'bulk', 'nodes', 'get', 'update', 'cat', 'mget'
+  }
+}
+
+testClusters.all {
+  // Needed in order to test ingest pipeline templating:
+  // (this is because the integTest node is not using default distribution, but only the minimal number of required modules)
+  module ':modules:lang-mustache'
+}
+
+thirdPartyAudit.ignoreMissingClasses(
+  // from log4j
+  'org.osgi.framework.AdaptPermission',
+  'org.osgi.framework.AdminPermission',
+  'org.osgi.framework.Bundle',
+  'org.osgi.framework.BundleActivator',
+  'org.osgi.framework.BundleContext',
+  'org.osgi.framework.BundleEvent',
+  'org.osgi.framework.SynchronousBundleListener',
+  'org.osgi.framework.wiring.BundleWire',
+  'org.osgi.framework.wiring.BundleWiring'
+)

modules/search-pipeline-common/src/internalClusterTest/java/org/opensearch/search/pipeline/common/SearchPipelineCommonIT.java

@@ -0,0 +1,13 @@
+/*
+ * 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.search.pipeline.common;
+
+import org.opensearch.test.OpenSearchIntegTestCase;
+
+public class SearchPipelineCommonIT extends OpenSearchIntegTestCase {}

modules/search-pipeline-common/src/main/java/org/opensearch/search/pipeline/common/AbstractProcessor.java

@@ -0,0 +1,34 @@
+/*
+ * 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.search.pipeline.common;
+
+import org.opensearch.search.pipeline.Processor;
+
+/**
+ * Base class for common processor behavior.
+ */
+abstract class AbstractProcessor implements Processor {
+    private final String tag;
+    private final String description;
+
+    protected AbstractProcessor(String tag, String description) {
+        this.tag = tag;
+        this.description = description;
+    }
+
+    @Override
+    public String getTag() {
+        return tag;
+    }
+
+    @Override
+    public String getDescription() {
+        return description;
+    }
+}

modules/search-pipeline-common/src/main/java/org/opensearch/search/pipeline/common/FilterQueryRequestProcessor.java

@@ -0,0 +1,117 @@
+/*
+ * 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.search.pipeline.common;
+
+import org.opensearch.action.search.SearchRequest;
+import org.opensearch.common.bytes.BytesReference;
+import org.opensearch.common.xcontent.LoggingDeprecationHandler;
+import org.opensearch.common.xcontent.XContentType;
+import org.opensearch.common.xcontent.json.JsonXContent;
+import org.opensearch.core.ParseField;
+import org.opensearch.core.xcontent.NamedXContentRegistry;
+import org.opensearch.core.xcontent.XContentBuilder;
+import org.opensearch.core.xcontent.XContentParser;
+import org.opensearch.index.query.BoolQueryBuilder;
+import org.opensearch.index.query.QueryBuilder;
+import org.opensearch.search.builder.SearchSourceBuilder;
+import org.opensearch.search.pipeline.Processor;
+import org.opensearch.search.pipeline.SearchRequestProcessor;
+
+import java.io.InputStream;
+import java.util.Map;
+
+import static org.opensearch.index.query.AbstractQueryBuilder.parseInnerQueryBuilder;
+
+/**
+ * This is a {@link SearchRequestProcessor} that replaces the incoming query with a BooleanQuery
+ * that MUST match the incoming query with a FILTER clause based on the configured query.
+ */
+public class FilterQueryRequestProcessor extends AbstractProcessor implements SearchRequestProcessor {
+    /**
+     * Key to reference this processor type from a search pipeline.
+     */
+    public static final String TYPE = "filter_query";
+
+    final QueryBuilder filterQuery;
+
+    @Override
+    public String getType() {
+        return TYPE;
+    }
+
+    /**
+     * Constructor that takes a filter query.
+     *
+     * @param tag         processor tag
+     * @param description processor description
+     * @param filterQuery the query that will be added as a filter to incoming queries
+     */
+    public FilterQueryRequestProcessor(String tag, String description, QueryBuilder filterQuery) {
+        super(tag, description);
+        this.filterQuery = filterQuery;
+    }
+
+    @Override
+    public SearchRequest processRequest(SearchRequest request) throws Exception {
+        QueryBuilder originalQuery = null;
+        if (request.source() != null) {
+            originalQuery = request.source().query();
+        }
+
+        BoolQueryBuilder filteredQuery = new BoolQueryBuilder().filter(filterQuery);
+        if (originalQuery != null) {
+            filteredQuery.must(originalQuery);
+        }
+        if (request.source() == null) {
+            request.source(new SearchSourceBuilder());
+        }
+        request.source().query(filteredQuery);
+        return request;
+    }
+
+    static class Factory implements Processor.Factory {
+        private final NamedXContentRegistry namedXContentRegistry;
+        public static final ParseField QUERY_FIELD = new ParseField("query");
+
+        Factory(NamedXContentRegistry namedXContentRegistry) {
+            this.namedXContentRegistry = namedXContentRegistry;
+        }
+
+        @Override
+        public FilterQueryRequestProcessor create(
+            Map<String, Processor.Factory> processorFactories,
+            String tag,
+            String description,
+            Map<String, Object> config
+        ) throws Exception {
+            try (
+                XContentBuilder builder = XContentBuilder.builder(JsonXContent.jsonXContent).map(config);
+                InputStream stream = BytesReference.bytes(builder).streamInput();
+                XContentParser parser = XContentType.JSON.xContent()
+                    .createParser(namedXContentRegistry, LoggingDeprecationHandler.INSTANCE, stream)
+            ) {
+                XContentParser.Token token = parser.nextToken();
+                assert token == XContentParser.Token.START_OBJECT;
+                String currentFieldName = null;
+                while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
+                    if (token == XContentParser.Token.FIELD_NAME) {
+                        currentFieldName = parser.currentName();
+                    } else if (token == XContentParser.Token.START_OBJECT) {
+                        if (QUERY_FIELD.match(currentFieldName, parser.getDeprecationHandler())) {
+                            return new FilterQueryRequestProcessor(tag, description, parseInnerQueryBuilder(parser));
+                        }
+                    }
+                }
+            }
+            throw new IllegalArgumentException(
+                "Did not specify the " + QUERY_FIELD.getPreferredName() + " property in processor of type " + TYPE
+            );
+        }
+    }
+}

modules/search-pipeline-common/src/main/java/org/opensearch/search/pipeline/common/SearchPipelineCommonModulePlugin.java

@@ -0,0 +1,31 @@
+/*
+ * 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.search.pipeline.common;
+
+import org.opensearch.plugins.Plugin;
+import org.opensearch.plugins.SearchPipelinesPlugin;
+import org.opensearch.search.pipeline.Processor;
+
+import java.util.Map;
+
+/**
+ * Plugin providing common search request/response processors for use in search pipelines.
+ */
+public class SearchPipelineCommonModulePlugin extends Plugin implements SearchPipelinesPlugin {
+
+    /**
+     * No constructor needed, but build complains if we don't have a constructor with JavaDoc.
+     */
+    public SearchPipelineCommonModulePlugin() {}
+
+    @Override
+    public Map<String, Processor.Factory> getProcessors(Processor.Parameters parameters) {
+        return Map.of(FilterQueryRequestProcessor.TYPE, new FilterQueryRequestProcessor.Factory(parameters.namedXContentRegistry));
+    }
+}

modules/search-pipeline-common/src/main/java/org/opensearch/search/pipeline/common/package-info.java

@@ -0,0 +1,12 @@
+/*
+ * 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.
+ */
+
+/**
+ * A collection of commonly-useful request and response processors for use in search pipelines.
+ */
+package org.opensearch.search.pipeline.common;

modules/search-pipeline-common/src/test/java/org/opensearch/search/pipeline/common/FilterQueryRequestProcessorTests.java

@@ -0,0 +1,51 @@
+/*
+ * 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.search.pipeline.common;
+
+import org.opensearch.action.search.SearchRequest;
+import org.opensearch.index.query.BoolQueryBuilder;
+import org.opensearch.index.query.QueryBuilder;
+import org.opensearch.index.query.TermQueryBuilder;
+import org.opensearch.search.builder.SearchSourceBuilder;
+import org.opensearch.test.AbstractBuilderTestCase;
+
+import java.util.Collections;
+import java.util.Map;
+
+public class FilterQueryRequestProcessorTests extends AbstractBuilderTestCase {
+
+    public void testFilterQuery() throws Exception {
+        QueryBuilder filterQuery = new TermQueryBuilder("field", "value");
+        FilterQueryRequestProcessor filterQueryRequestProcessor = new FilterQueryRequestProcessor(null, null, filterQuery);
+        QueryBuilder incomingQuery = new TermQueryBuilder("text", "foo");
+        SearchSourceBuilder source = new SearchSourceBuilder().query(incomingQuery);
+        SearchRequest request = new SearchRequest().source(source);
+        SearchRequest transformedRequest = filterQueryRequestProcessor.processRequest(request);
+        assertEquals(new BoolQueryBuilder().must(incomingQuery).filter(filterQuery), transformedRequest.source().query());
+
+        // Test missing incoming query
+        request = new SearchRequest();
+        transformedRequest = filterQueryRequestProcessor.processRequest(request);
+        assertEquals(new BoolQueryBuilder().filter(filterQuery), transformedRequest.source().query());
+    }
+
+    public void testFactory() throws Exception {
+        FilterQueryRequestProcessor.Factory factory = new FilterQueryRequestProcessor.Factory(this.xContentRegistry());
+        FilterQueryRequestProcessor processor = factory.create(
+            Collections.emptyMap(),
+            null,
+            null,
+            Map.of("query", Map.of("term", Map.of("field", "value")))
+        );
+        assertEquals(new TermQueryBuilder("field", "value"), processor.filterQuery);
+
+        // Missing "query" parameter:
+        expectThrows(IllegalArgumentException.class, () -> factory.create(Collections.emptyMap(), null, null, Collections.emptyMap()));
+    }
+}

modules/search-pipeline-common/src/yamlRestTest/java/org/opensearch/search/pipeline/common/SearchPipelineCommonYamlTestSuiteIT.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.search.pipeline.common;
+
+import com.carrotsearch.randomizedtesting.annotations.Name;
+import com.carrotsearch.randomizedtesting.annotations.ParametersFactory;
+import org.opensearch.test.rest.yaml.ClientYamlTestCandidate;
+import org.opensearch.test.rest.yaml.OpenSearchClientYamlSuiteTestCase;
+
+public class SearchPipelineCommonYamlTestSuiteIT extends OpenSearchClientYamlSuiteTestCase {
+    public SearchPipelineCommonYamlTestSuiteIT(@Name("yaml") ClientYamlTestCandidate testCandidate) {
+        super(testCandidate);
+    }
+
+    @ParametersFactory
+    public static Iterable<Object[]> parameters() throws Exception {
+        return OpenSearchClientYamlSuiteTestCase.createParameters();
+    }
+}

modules/search-pipeline-common/src/yamlRestTest/resources/rest-api-spec/test/search_pipeline/10_basic.yml

@@ -0,0 +1,15 @@
+"Search pipeline common installed":
+  - skip:
+      reason: "contains is a newly added assertion"
+      features: contains
+  - do:
+      cluster.state: {}
+
+  # Get cluster-manager node id
+  - set: { cluster_manager_node: cluster_manager }
+
+  - do:
+      nodes.info: {}
+
+  - contains:  { nodes.$cluster_manager.modules: { name: search-pipeline-common } }
+  - contains:  { nodes.$cluster_manager.search_pipelines.processors: { type: filter_query } }