Plugin Framework

/**
 * Base plugin class providing extension points for all OpenSearch functionality
 */
abstract class Plugin implements Closeable {
    /**
     * Get plugin description information
     */
    String getDescription();
    
    /**
     * Create Guice modules for dependency injection
     * @return Collection of Guice modules to register
     */
    Collection<Module> createGuiceModules();
    
    /**
     * Provide additional settings that should be added to the cluster
     * @return Settings to add to cluster configuration
     */
    Settings additionalSettings();
    
    /**
     * Get list of setting definitions for this plugin
     * @return List of setting definitions
     */
    List<Setting<?>> getSettings();
    
    /**
     * Get list of settings that require keystore access
     * @return List of secure setting definitions
     */
    List<Setting<?>> getSecureSettings();
    
    /**
     * Called when plugin is closed during shutdown
     */
    void close() throws IOException;
    
    /**
     * Get plugin classloader for loading plugin resources
     */
    ClassLoader getPluginClassLoader();
}

/**
 * Plugin information container with metadata and dependencies
 */
class PluginInfo implements Streamable {
    /**
     * Create plugin info
     * @param name Plugin name
     * @param description Plugin description
     * @param version Plugin version
     * @param classname Main plugin class name
     * @param hasNativeController Whether plugin has native controller
     */
    PluginInfo(String name, String description, String version, String classname, 
               boolean hasNativeController);
    
    /**
     * Get plugin name
     */
    String getName();
    
    /**
     * Get plugin description
     */
    String getDescription();
    
    /**
     * Get plugin version
     */
    String getVersion();
    
    /**
     * Get main plugin class name
     */
    String getClassname();
    
    /**
     * Check if plugin has native controller
     */
    boolean hasNativeController();
    
    /**
     * Get OpenSearch version compatibility
     */
    String getOpenSearchVersion();
    
    /**
     * Get Java version requirement
     */
    String getJavaVersion();
}

/**
 * Service for managing plugin lifecycle and registration
 */
class PluginsService {
    /**
     * Create plugins service with configuration
     * @param settings OpenSearch settings
     * @param modulesDirectory Modules directory path
     * @param pluginsDirectory Plugins directory path
     * @param classpathPlugins Classpath plugin classes
     */
    PluginsService(Settings settings, Path modulesDirectory, Path pluginsDirectory, 
                   Collection<Class<? extends Plugin>> classpathPlugins);
    
    /**
     * Get all loaded plugins
     */
    List<Tuple<PluginInfo, Plugin>> plugins();
    
    /**
     * Get plugins filtered by type
     * @param type Plugin interface class
     */
    <T> List<T> filterPlugins(Class<T> type);
    
    /**
     * Get plugin info by name
     * @param name Plugin name
     */
    PluginInfo getPluginInfo(String name);
    
    /**
     * Check if plugin is loaded
     * @param name Plugin name
     */
    boolean isPluginLoaded(String name);
}

/**
 * Plugin interface for providing custom actions and REST handlers
 */
interface ActionPlugin {
    /**
     * Get list of action handlers provided by this plugin
     * @return List of action handler registrations
     */
    List<ActionHandler<? extends ActionRequest, ? extends ActionResponse>> getActions();
    
    /**
     * Get list of REST handlers provided by this plugin
     * @param settings Cluster settings
     * @param restController REST controller for registration
     * @param clusterSettings Cluster settings manager
     * @param indexScopedSettings Index-scoped settings manager
     * @param settingsFilter Settings filter for security
     * @param indexNameExpressionResolver Index name pattern resolver
     * @param nodesInCluster Supplier for cluster nodes information
     * @return List of REST handler implementations
     */
    List<RestHandler> getRestHandlers(Settings settings, RestController restController,
        ClusterSettings clusterSettings, IndexScopedSettings indexScopedSettings,
        SettingsFilter settingsFilter, IndexNameExpressionResolver indexNameExpressionResolver,
        Supplier<DiscoveryNodes> nodesInCluster);
    
    /**
     * Get list of action filters for intercepting requests
     * @return List of action filter implementations
     */
    default List<ActionFilter> getActionFilters() {
        return Collections.emptyList();
    }
    
    /**
     * Get list of task headers that should be preserved across requests
     * @return Collection of header names to preserve
     */
    default Collection<String> getTaskHeaders() {
        return Collections.emptyList();
    }
}

/**
 * Registration container for action handlers
 */
class ActionHandler<Request extends ActionRequest, Response extends ActionResponse> {
    /**
     * Create action handler registration
     * @param action Action type definition
     * @param transportAction Transport action implementation class
     */
    ActionHandler(ActionType<Response> action, 
                  Class<? extends TransportAction<Request, Response>> transportAction);
    
    /**
     * Create action handler with support actions
     * @param action Action type definition
     * @param transportAction Transport action implementation class
     * @param supportTransportActions Additional support action classes
     */
    ActionHandler(ActionType<Response> action,
                  Class<? extends TransportAction<Request, Response>> transportAction,
                  Class<?>... supportTransportActions);
    
    /**
     * Get action type
     */
    ActionType<Response> getAction();
    
    /**
     * Get transport action class
     */
    Class<? extends TransportAction<Request, Response>> getTransportAction();
    
    /**
     * Get support transport action classes
     */
    Class<?>[] getSupportTransportActions();
}

/**
 * Base class for REST request handlers
 */
abstract class BaseRestHandler implements RestHandler {
    /**
     * Get routes supported by this handler
     * @return List of route definitions
     */
    abstract List<Route> routes();
    
    /**
     * Handle REST request
     * @param request REST request
     * @param channel Response channel
     * @param client OpenSearch client
     */
    abstract RestChannelConsumer prepareRequest(RestRequest request, NodeClient client) 
        throws IOException;
    
    /**
     * Check if request can be handled without content
     */
    protected boolean canTripCircuitBreaker() {
        return true;
    }
    
    /**
     * Check if handler supports working with content streams
     */
    protected boolean supportsContentStream() {
        return false;
    }
}

/**
 * Plugin interface for extending search functionality
 */
interface SearchPlugin {
    /**
     * Get custom query builders provided by this plugin
     * @return List of query builder registrations
     */
    default List<QuerySpec<?>> getQueries() {
        return Collections.emptyList();
    }
    
    /**
     * Get custom aggregation builders provided by this plugin
     * @return List of aggregation builder registrations
     */
    default List<AggregationSpec> getAggregations() {
        return Collections.emptyList();
    }
    
    /**
     * Get custom pipeline aggregations provided by this plugin
     * @return List of pipeline aggregation registrations
     */
    default List<PipelineAggregationSpec> getPipelineAggregations() {
        return Collections.emptyList();
    }
    
    /**
     * Get custom function score functions provided by this plugin
     * @return List of score function registrations
     */
    default List<ScoreFunctionSpec<?>> getScoreFunctions() {
        return Collections.emptyList();
    }
    
    /**
     * Get custom significance heuristics provided by this plugin
     * @return List of significance heuristic registrations
     */
    default List<SignificanceHeuristicSpec<?>> getSignificanceHeuristics() {
        return Collections.emptyList();
    }
    
    /**
     * Get custom MovAvg models provided by this plugin
     * @return List of moving average model registrations
     */
    default List<MovAvgModelSpec> getMovingAverageModels() {
        return Collections.emptyList();
    }
    
    /**
     * Get custom fetch sub-phases provided by this plugin
     * @return List of fetch sub-phase implementations
     */
    default List<FetchSubPhase> getFetchSubPhases(FetchPhaseConstructionContext context) {
        return Collections.emptyList();
    }
    
    /**
     * Get custom search extensions provided by this plugin
     * @return List of search extension implementations
     */
    default List<SearchExtension> getSearchExtensions() {
        return Collections.emptyList();
    }
}

/**
 * Query builder specification for plugin registration
 */
class QuerySpec<T extends QueryBuilder> implements NamedWriteable.Entry<QueryBuilder> {
    /**
     * Create query spec
     * @param name Query name for parsing
     * @param reader Reader function for deserialization
     * @param parser Parser function for XContent parsing
     */
    QuerySpec(String name, Writeable.Reader<T> reader, CheckedFunction<XContentParser, T, IOException> parser);
    
    /**
     * Get query name
     */
    String getName();
    
    /**
     * Get query class
     */
    Class<T> getQueryClass();
}

/**
 * Aggregation specification for plugin registration
 */
class AggregationSpec implements NamedWriteable.Entry<AggregationBuilder> {
    /**
     * Create aggregation spec
     * @param name Aggregation name
     * @param reader Reader function for deserialization
     * @param parser Parser function for XContent parsing
     */
    AggregationSpec(String name, Writeable.Reader<? extends AggregationBuilder> reader,
        AggregationParser parser);
    
    /**
     * Get aggregation name
     */
    String getName();
    
    /**
     * Get aggregation builder class
     */
    Class<? extends AggregationBuilder> getBuilderClass();
}

/**
 * Plugin interface for providing text analysis components
 */
interface AnalysisPlugin {
    /**
     * Get custom analyzers provided by this plugin
     * @return Map of analyzer name to analyzer provider
     */
    default Map<String, AnalysisProvider<AnalyzerProvider<? extends Analyzer>>> getAnalyzers() {
        return Collections.emptyMap();
    }
    
    /**
     * Get custom character filters provided by this plugin
     * @return Map of char filter name to char filter provider
     */
    default Map<String, AnalysisProvider<CharFilterFactory>> getCharFilters() {
        return Collections.emptyMap();
    }
    
    /**
     * Get custom tokenizers provided by this plugin
     * @return Map of tokenizer name to tokenizer provider
     */
    default Map<String, AnalysisProvider<TokenizerFactory>> getTokenizers() {
        return Collections.emptyMap();
    }
    
    /**
     * Get custom token filters provided by this plugin
     * @return Map of token filter name to token filter provider
     */
    default Map<String, AnalysisProvider<TokenFilterFactory>> getTokenFilters() {
        return Collections.emptyMap();
    }
    
    /**
     * Get custom hunspell dictionaries provided by this plugin
     * @return Map of language to hunspell dictionary
     */
    default Map<String, Dictionary> getHunspellDictionaries() {
        return Collections.emptyMap();
    }
    
    /**
     * Get custom normalizers provided by this plugin
     * @return Map of normalizer name to normalizer provider
     */
    default Map<String, AnalysisProvider<AnalyzerProvider<? extends Analyzer>>> getNormalizers() {
        return Collections.emptyMap();
    }
}

/**
 * Provider interface for analysis components
 */
interface AnalysisProvider<T> {
    /**
     * Create analysis component instance
     * @param indexSettings Index settings context
     * @param environment Plugin environment
     * @param name Component name
     * @param settings Component settings
     */
    T get(IndexSettings indexSettings, Environment environment, String name, Settings settings);
}

/**
 * Factory interface for creating analyzers
 */
interface AnalyzerProvider<T extends Analyzer> extends Closeable {
    /**
     * Get analyzer instance
     */
    T get();
    
    /**
     * Close analyzer and release resources
     */
    void close();
}

/**
 * Factory interface for creating character filters
 */
interface CharFilterFactory {
    /**
     * Get character filter name
     */
    String name();
    
    /**
     * Create character filter reader
     * @param reader Input character reader
     */
    Reader create(Reader reader);
}

/**
 * Factory interface for creating tokenizers
 */
interface TokenizerFactory {
    /**
     * Create tokenizer instance
     */
    Tokenizer create();
}

/**
 * Factory interface for creating token filters
 */
interface TokenFilterFactory {
    /**
     * Create token filter instance
     * @param tokenStream Input token stream
     */
    TokenStream create(TokenStream tokenStream);
}

/**
 * Plugin interface for providing custom field mappers
 */
interface MapperPlugin {
    /**
     * Get custom field mappers provided by this plugin
     * @return Map of type name to mapper parser
     */
    Map<String, Mapper.TypeParser> getMappers();
    
    /**
     * Get custom metadata mappers provided by this plugin
     * @return Map of name to metadata mapper parser
     */
    default Map<String, MetadataFieldMapper.TypeParser> getMetadataMappers() {
        return Collections.emptyMap();
    }
    
    /**
     * Get custom field filter provided by this plugin
     * @return Field filter implementation
     */
    default Function<String, Predicate<String>> getFieldFilter() {
        return MapperPlugin.NOOP_FIELD_FILTER;
    }
    
    /**
     * No-op field filter that allows all fields
     */
    Function<String, Predicate<String>> NOOP_FIELD_FILTER = index -> field -> true;
}

/**
 * Base mapper for field mapping implementations
 */
abstract class Mapper implements Streamable {
    /**
     * Get mapper name
     */
    String name();
    
    /**
     * Get mapper type name
     */
    abstract String typeName();
    
    /**
     * Merge with another mapper
     * @param mergeWith Mapper to merge with
     * @param mergeReason Reason for merge operation
     */
    abstract Mapper merge(Mapper mergeWith, MergeReason mergeReason);
    
    /**
     * Validate field mapping configuration
     * @param indexSettings Index settings context
     */
    abstract void validate(MappingLookup mappers, IndexSettings indexSettings);
    
    /**
     * Type parser interface for creating mapper instances
     */
    interface TypeParser {
        /**
         * Parse mapper configuration and create mapper builder
         * @param name Field name
         * @param node Mapping configuration
         * @param parserContext Parser context
         */
        Builder parse(String name, Map<String, Object> node, ParserContext parserContext)
            throws MapperParsingException;
    }
    
    /**
     * Builder interface for constructing mappers
     */
    abstract static class Builder {
        /**
         * Build mapper instance
         * @param context Build context
         */
        abstract Mapper build(ContentPath contentPath, MapperBuilderContext context);
    }
}

/**
 * Plugin interface for providing custom ingest processors
 */
interface IngestPlugin {
    /**
     * Get custom processors provided by this plugin
     * @param processorFactories Existing processor factories
     * @return Map of processor name to processor factory
     */
    Map<String, Processor.Factory> getProcessors(Processor.Parameters processorFactories);
    
    /**
     * Get additional ingest capabilities provided by this plugin
     * @return List of ingest capability extensions
     */
    default List<IngestCapability> getIngestCapabilities() {
        return Collections.emptyList();
    }
}

/**
 * Base processor interface for document processing in ingest pipelines
 */
interface Processor {
    /**
     * Get processor type name
     */
    String getType();
    
    /**
     * Get processor tag for identification
     */
    String getTag();
    
    /**
     * Get processor description
     */
    String getDescription();
    
    /**
     * Execute processor on ingest document
     * @param ingestDocument Document to process
     * @return Processed ingest document
     */
    IngestDocument execute(IngestDocument ingestDocument) throws Exception;
    
    /**
     * Factory interface for creating processor instances
     */
    interface Factory {
        /**
         * Create processor instance
         * @param processorFactories Available processor factories
         * @param tag Processor tag
         * @param description Processor description
         * @param config Processor configuration
         */
        Processor create(Map<String, Factory> processorFactories, String tag, 
                        String description, Map<String, Object> config) throws Exception;
    }
    
    /**
     * Parameters container for processor factory access
     */
    class Parameters {
        /**
         * Get environment configuration
         */
        public Environment env;
        
        /**
         * Get script service for script processors
         */
        public ScriptService scriptService;
        
        /**
         * Get analysis registry for text analysis
         */
        public AnalysisRegistry analysisRegistry;
        
        /**
         * Get thread pool for async operations
         */
        public ThreadPool threadPool;
        
        /**
         * Get ingest service reference
         */
        public IngestService ingestService;
    }
}

/**
 * Abstract base class for simple processor implementations
 */
abstract class AbstractProcessor implements Processor {
    /**
     * Create abstract processor
     * @param tag Processor tag
     * @param description Processor description
     */
    protected AbstractProcessor(String tag, String description);
    
    /**
     * Get processor tag
     */
    String getTag();
    
    /**
     * Get processor description
     */
    String getDescription();
}

/**
 * Plugin interface for providing custom snapshot repositories
 */
interface RepositoryPlugin {
    /**
     * Get custom repository types provided by this plugin
     * @return Map of repository type to repository factory
     */
    Map<String, Repository.Factory> getRepositories(Environment env, NamedXContentRegistry namedXContentRegistry,
        ClusterService clusterService, BigArrays bigArrays, RecoverySettings recoverySettings);
    
    /**
     * Get custom repository cleanup extensions
     * @return Map of repository type to cleanup extensions
     */
    default Map<String, Repository.Factory> getInternalRepositories(Environment env, 
        NamedXContentRegistry namedXContentRegistry, ClusterService clusterService,
        RecoverySettings recoverySettings) {
        return Collections.emptyMap();
    }
}

/**
 * Base repository interface for snapshot storage implementations
 */
interface Repository extends Closeable {
    /**
     * Get repository metadata
     */
    RepositoryMetadata getMetadata();
    
    /**
     * Initialize repository with cluster state
     * @param clusterState Current cluster state
     */
    void initializeSnapshot(SnapshotId snapshotId, List<IndexId> indices, Metadata metadata);
    
    /**
     * Finalize snapshot creation
     * @param finalizeContext Snapshot finalization context
     */
    SnapshotInfo finalizeSnapshot(FinalizeSnapshotContext finalizeContext);
    
    /**
     * Delete snapshot from repository
     * @param snapshotId Snapshot to delete
     * @param repositoryStateId Repository state version
     * @param writeShardGens Whether to write shard generation files
     * @param listener Completion callback
     */
    void deleteSnapshots(Collection<SnapshotId> snapshotIds, long repositoryStateId,
        boolean writeShardGens, ActionListener<RepositoryData> listener);
    
    /**
     * Factory interface for creating repository instances
     */
    interface Factory {
        /**
         * Create repository instance
         * @param metadata Repository metadata configuration
         */
        Repository create(RepositoryMetadata metadata) throws Exception;
        
        /**
         * Create repository instance with recovery settings
         * @param metadata Repository metadata configuration
         * @param typeLookup Type lookup for deserialization
         */
        Repository create(RepositoryMetadata metadata, Function<String, Repository.Factory> typeLookup) 
            throws Exception;
    }
}

import org.opensearch.plugins.ActionPlugin;
import org.opensearch.plugins.Plugin;
import org.opensearch.rest.BaseRestHandler;
import org.opensearch.rest.RestRequest;
import org.opensearch.client.node.NodeClient;

/**
 * Example plugin that provides a custom action and REST endpoint
 */
public class CustomActionPlugin extends Plugin implements ActionPlugin {
    
    @Override
    public List<ActionHandler<? extends ActionRequest, ? extends ActionResponse>> getActions() {
        return List.of(
            new ActionHandler<>(CustomAction.INSTANCE, TransportCustomAction.class)
        );
    }
    
    @Override
    public List<RestHandler> getRestHandlers(Settings settings, RestController restController,
            ClusterSettings clusterSettings, IndexScopedSettings indexScopedSettings,
            SettingsFilter settingsFilter, IndexNameExpressionResolver indexNameExpressionResolver,
            Supplier<DiscoveryNodes> nodesInCluster) {
        
        return List.of(new RestCustomHandler());
    }
}

/**
 * Custom action type definition
 */
public class CustomAction extends ActionType<CustomResponse> {
    public static final CustomAction INSTANCE = new CustomAction();
    public static final String NAME = "cluster:admin/custom_action";
    
    private CustomAction() {
        super(NAME, CustomResponse::new);
    }
}

/**
 * Custom action request
 */
public class CustomRequest extends ActionRequest {
    private String parameter;
    
    public CustomRequest(String parameter) {
        this.parameter = parameter;
    }
    
    public String getParameter() {
        return parameter;
    }
    
    @Override
    public ActionRequestValidationException validate() {
        if (parameter == null || parameter.isEmpty()) {
            ActionRequestValidationException validationException = new ActionRequestValidationException();
            validationException.addValidationError("parameter cannot be null or empty");
            return validationException;
        }
        return null;
    }
}

/**
 * Custom action response
 */
public class CustomResponse extends ActionResponse {
    private String result;
    
    public CustomResponse(String result) {
        this.result = result;
    }
    
    public String getResult() {
        return result;
    }
    
    @Override
    public void writeTo(StreamOutput out) throws IOException {
        out.writeString(result);
    }
}

/**
 * REST handler for custom action
 */
public class RestCustomHandler extends BaseRestHandler {
    
    @Override
    public List<Route> routes() {
        return List.of(
            new Route(GET, "/_custom/{param}"),
            new Route(POST, "/_custom/{param}")
        );
    }
    
    @Override
    public String getName() {
        return "custom_action_handler";
    }
    
    @Override
    protected RestChannelConsumer prepareRequest(RestRequest request, NodeClient client) throws IOException {
        String param = request.param("param");
        CustomRequest customRequest = new CustomRequest(param);
        
        return channel -> client.execute(CustomAction.INSTANCE, customRequest,
            new RestToXContentListener<>(channel));
    }
}

import org.opensearch.plugins.SearchPlugin;
import org.opensearch.index.query.QueryBuilder;
import org.opensearch.index.query.AbstractQueryBuilder;

/**
 * Plugin providing a custom query builder
 */
public class CustomQueryPlugin extends Plugin implements SearchPlugin {
    
    @Override
    public List<QuerySpec<?>> getQueries() {
        return List.of(
            new QuerySpec<>(
                CustomQueryBuilder.NAME,
                CustomQueryBuilder::new,
                CustomQueryBuilder::fromXContent
            )
        );
    }
}

/**
 * Custom query builder implementation
 */
public class CustomQueryBuilder extends AbstractQueryBuilder<CustomQueryBuilder> {
    public static final String NAME = "custom_query";
    
    private final String field;
    private final String value;
    private final float boost;
    
    public CustomQueryBuilder(String field, String value) {
        this.field = field;
        this.value = value;
        this.boost = 1.0f;
    }
    
    public CustomQueryBuilder boost(float boost) {
        return new CustomQueryBuilder(field, value).boost(boost);
    }
    
    @Override
    protected void doWriteTo(StreamOutput out) throws IOException {
        out.writeString(field);
        out.writeString(value);
        out.writeFloat(boost);
    }
    
    @Override
    protected void doXContent(XContentBuilder builder, Params params) throws IOException {
        builder.startObject(NAME);
        builder.startObject(field);
        builder.field("value", value);
        if (boost != 1.0f) {
            builder.field("boost", boost);
        }
        builder.endObject();
        builder.endObject();
    }
    
    public static CustomQueryBuilder fromXContent(XContentParser parser) throws IOException {
        // Implementation for parsing from XContent
        // ... parsing logic here
        return new CustomQueryBuilder("field", "value");
    }
    
    @Override
    protected Query doToQuery(QueryShardContext context) throws IOException {
        // Convert to Lucene query
        return new TermQuery(new Term(field, value));
    }
    
    @Override
    protected boolean doEquals(CustomQueryBuilder other) {
        return Objects.equals(field, other.field) &&
               Objects.equals(value, other.value) &&
               Float.compare(boost, other.boost) == 0;
    }
    
    @Override
    protected int doHashCode() {
        return Objects.hash(field, value, boost);
    }
    
    @Override
    public String getWriteableName() {
        return NAME;
    }
}

import org.opensearch.plugins.AnalysisPlugin;
import org.opensearch.index.analysis.TokenFilterFactory;

/**
 * Plugin providing custom text analysis components
 */
public class CustomAnalysisPlugin extends Plugin implements AnalysisPlugin {
    
    @Override
    public Map<String, AnalysisProvider<TokenFilterFactory>> getTokenFilters() {
        return Map.of("custom_filter", CustomTokenFilterFactory::new);
    }
    
    @Override
    public Map<String, AnalysisProvider<AnalyzerProvider<? extends Analyzer>>> getAnalyzers() {
        return Map.of("custom_analyzer", CustomAnalyzerProvider::new);
    }
}

/**
 * Custom token filter factory
 */
public class CustomTokenFilterFactory implements TokenFilterFactory {
    private final Settings settings;
    
    public CustomTokenFilterFactory(IndexSettings indexSettings, Environment environment,
                                    String name, Settings settings) {
        this.settings = settings;
    }
    
    @Override
    public String name() {
        return "custom_filter";
    }
    
    @Override
    public TokenStream create(TokenStream tokenStream) {
        return new CustomTokenFilter(tokenStream, settings);
    }
}

/**
 * Custom token filter implementation
 */
public class CustomTokenFilter extends TokenFilter {
    private final CharTermAttribute termAttribute;
    private final Settings settings;
    
    public CustomTokenFilter(TokenStream input, Settings settings) {
        super(input);
        this.settings = settings;
        this.termAttribute = addAttribute(CharTermAttribute.class);
    }
    
    @Override
    public boolean incrementToken() throws IOException {
        if (input.incrementToken()) {
            // Custom token processing logic
            String term = termAttribute.toString();
            String processed = processTerm(term);
            termAttribute.setEmpty().append(processed);
            return true;
        }
        return false;
    }
    
    private String processTerm(String term) {
        // Custom processing logic
        return term.toLowerCase();
    }
}

/**
 * Custom analyzer provider
 */
public class CustomAnalyzerProvider implements AnalyzerProvider<Analyzer> {
    private final Analyzer analyzer;
    
    public CustomAnalyzerProvider(IndexSettings indexSettings, Environment environment,
                                  String name, Settings settings) {
        this.analyzer = new CustomAnalyzer(settings);
    }
    
    @Override
    public Analyzer get() {
        return analyzer;
    }
    
    @Override
    public void close() {
        // Cleanup if needed
    }
}

import org.opensearch.plugins.IngestPlugin;
import org.opensearch.ingest.Processor;
import org.opensearch.ingest.AbstractProcessor;
import org.opensearch.ingest.IngestDocument;

/**
 * Plugin providing custom ingest processors
 */
public class CustomIngestPlugin extends Plugin implements IngestPlugin {
    
    @Override
    public Map<String, Processor.Factory> getProcessors(Processor.Parameters parameters) {
        return Map.of("custom_processor", new CustomProcessorFactory());
    }
}

/**
 * Factory for creating custom processor instances
 */
public class CustomProcessorFactory implements Processor.Factory {
    
    @Override
    public CustomProcessor create(Map<String, Processor.Factory> processorFactories,
                                  String tag, String description, Map<String, Object> config) {
        String field = ConfigurationUtils.readStringProperty("custom_processor", tag, config, "field");
        String value = ConfigurationUtils.readStringProperty("custom_processor", tag, config, "value");
        boolean ignoreMissing = ConfigurationUtils.readBooleanProperty("custom_processor", tag, config, 
            "ignore_missing", false);
        
        return new CustomProcessor(tag, description, field, value, ignoreMissing);
    }
}

/**
 * Custom ingest processor implementation
 */
public class CustomProcessor extends AbstractProcessor {
    public static final String TYPE = "custom_processor";
    
    private final String field;
    private final String value;
    private final boolean ignoreMissing;
    
    public CustomProcessor(String tag, String description, String field, String value, boolean ignoreMissing) {
        super(tag, description);
        this.field = field;
        this.value = value;
        this.ignoreMissing = ignoreMissing;
    }
    
    @Override
    public String getType() {
        return TYPE;
    }
    
    @Override
    public IngestDocument execute(IngestDocument ingestDocument) throws Exception {
        if (!ingestDocument.hasField(field)) {
            if (ignoreMissing) {
                return ingestDocument;
            } else {
                throw new IllegalArgumentException("Field [" + field + "] does not exist");
            }
        }
        
        // Custom processing logic
        String currentValue = ingestDocument.getFieldValue(field, String.class);
        String processedValue = processValue(currentValue);
        ingestDocument.setFieldValue(field, processedValue);
        
        return ingestDocument;
    }
    
    private String processValue(String input) {
        // Custom value processing
        return input + "_" + value;
    }
}

/**
 * Plugin environment providing access to configuration and resources
 */
class Environment {
    /**
     * Get settings configuration
     */
    Settings settings();
    
    /**
     * Get config directory path
     */
    Path configDir();
    
    /**
     * Get plugins directory path
     */
    Path pluginsDir();
    
    /**
     * Get modules directory path
     */
    Path modulesDir();
    
    /**
     * Get logs directory path
     */
    Path logsDir();
    
    /**
     * Get temporary directory path
     */
    Path tmpDir();
}

/**
 * Route definition for REST handlers
 */
class Route {
    /**
     * Create route with method and path
     * @param method HTTP method
     * @param path URL path pattern
     */
    Route(RestRequest.Method method, String path);
    
    /**
     * Create route with method, path, and deprecation message
     * @param method HTTP method
     * @param path URL path pattern
     * @param deprecationMessage Deprecation warning message
     */
    Route(RestRequest.Method method, String path, String deprecationMessage);
    
    /**
     * Get HTTP method
     */
    RestRequest.Method getMethod();
    
    /**
     * Get path pattern
     */
    String getPath();
    
    /**
     * Get deprecation message
     */
    String getDeprecationMessage();
}

/**
 * Transport action base class for handling cluster operations
 */
abstract class TransportAction<Request extends ActionRequest, Response extends ActionResponse> {
    /**
     * Execute action with request and response listener
     * @param task Task context
     * @param request Action request
     * @param listener Response callback
     */
    protected abstract void doExecute(Task task, Request request, ActionListener<Response> listener);
    
    /**
     * Get action name
     */
    String actionName();
    
    /**
     * Get transport service
     */
    protected TransportService transportService();
    
    /**
     * Get cluster service
     */
    protected ClusterService clusterService();
}

/**
 * Setting definition for plugin configuration
 */
class Setting<T> {
    /**
     * Create setting with key and default value
     * @param key Setting key
     * @param defaultValue Default value
     * @param parser Value parser function
     * @param properties Setting properties
     */
    static <T> Setting<T> simpleString(String key, String defaultValue, Property... properties);
    
    /**
     * Create integer setting
     * @param key Setting key
     * @param defaultValue Default integer value
     * @param minValue Minimum allowed value
     * @param properties Setting properties
     */
    static Setting<Integer> intSetting(String key, int defaultValue, int minValue, Property... properties);
    
    /**
     * Create boolean setting
     * @param key Setting key
     * @param defaultValue Default boolean value
     * @param properties Setting properties
     */
    static Setting<Boolean> boolSetting(String key, boolean defaultValue, Property... properties);
    
    /**
     * Get setting key
     */
    String getKey();
    
    /**
     * Get default value
     */
    T getDefault(Settings settings);
    
    /**
     * Setting properties enumeration
     */
    enum Property {
        DYNAMIC, INDEX_SCOPE, CLUSTER_SCOPE, DEPRECATED, FILTERED
    }
}