node-liblzma/lib/pool.d.ts

NodeJS wrapper for liblzma

/**
 * node-liblzma - Node.js bindings for liblzma
 * Copyright (C) Olivier Orabona <olivier.orabona@gmail.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
import { EventEmitter } from 'node:events';
import { type LZMAOptions } from './lzma.js';
/**
 * Metrics for pool monitoring
 */
export interface PoolMetrics {
    /** Number of currently active compression/decompression operations */
    active: number;
    /** Number of operations waiting in the queue */
    queued: number;
    /** Total number of successfully completed operations */
    completed: number;
    /** Total number of failed operations */
    failed: number;
}
/**
 * LZMA Pool with concurrency control and event monitoring
 *
 * Provides rate limiting and backpressure for LZMA operations.
 * Emits events for monitoring and metrics collection in production.
 *
 * @example
 * ```typescript
 * const pool = new LZMAPool(10); // Max 10 concurrent operations
 *
 * pool.on('metrics', (metrics) => {
 *   console.log(`Active: ${metrics.active}, Queued: ${metrics.queued}`);
 * });
 *
 * const compressed = await pool.compress(buffer);
 * ```
 *
 * Events:
 * - 'queue': Emitted when task added to queue
 * - 'start': Emitted when task starts processing
 * - 'complete': Emitted when task completes successfully
 * - 'error-task': Emitted when task fails
 * - 'metrics': Emitted after each state change with current metrics
 */
export declare class LZMAPool extends EventEmitter {
    private maxConcurrent;
    private queue;
    private metrics;
    /**
     * Create a new LZMA pool
     * @param maxConcurrent Maximum number of concurrent operations (default: 10)
     */
    constructor(maxConcurrent?: number);
    /**
     * Compress data with automatic queue management
     * @param data Buffer to compress
     * @param opts LZMA compression options
     * @returns Promise that resolves to compressed buffer
     */
    compress(data: Buffer, opts?: LZMAOptions): Promise<Buffer>;
    /**
     * Decompress data with automatic queue management
     * @param data Compressed buffer to decompress
     * @param opts LZMA decompression options
     * @returns Promise that resolves to decompressed buffer
     */
    decompress(data: Buffer, opts?: LZMAOptions): Promise<Buffer>;
    /**
     * Get current pool metrics
     * @returns Copy of current metrics
     */
    getMetrics(): Readonly<PoolMetrics>;
    /**
     * Get number of tasks waiting in queue
     * @returns Queue length
     */
    get queueLength(): number;
    /**
     * Get number of currently active tasks
     * @returns Active task count
     */
    get activeCount(): number;
    /**
     * Check if pool is at maximum capacity
     * @returns True if at capacity
     */
    get isAtCapacity(): boolean;
    /**
     * Enqueue a task for execution
     * @param fn Task function returning Promise<Buffer>
     * @returns Promise that resolves when task completes
     */
    private enqueue;
    /**
     * Process tasks from queue respecting concurrency limit
     */
    private processQueue;
    /**
     * Wait for all active tasks to complete
     * Does not process new tasks added while waiting
     * @returns Promise that resolves when all active tasks are done
     */
    drain(): Promise<void>;
    /**
     * Clear all pending tasks from the queue
     * Active tasks will continue to run
     * @returns Number of tasks removed from queue
     */
    clearQueue(): number;
}
//# sourceMappingURL=pool.d.ts.map