@dooor-ai/toolkit/src/guards/base.ts

Guards, Evals & Observability for AI applications - works seamlessly with LangChain/LangGraph

import { GuardResult, GuardConfig } from "../core/types";

/**
 * Abstract base class for all guards
 */
export abstract class Guard {
  protected config: GuardConfig;

  constructor(config: GuardConfig = {}) {
    this.config = {
      threshold: 0.8,
      blockOnDetection: true,
      enabled: true,
      ...config,
    };
  }

  /**
   * Get the name of this guard
   */
  abstract get name(): string;

  /**
   * Validate the input
   * @param input - The input text to validate
   * @param metadata - Additional metadata (e.g., user info, session)
   * @returns GuardResult indicating if input passed
   */
  abstract validate(
    input: string,
    metadata?: Record<string, any>
  ): Promise<GuardResult> | GuardResult;

  /**
   * Check if this guard is enabled
   */
  isEnabled(): boolean {
    return this.config.enabled ?? true;
  }

  /**
   * Check if guard should block on detection
   */
  shouldBlock(): boolean {
    return this.config.blockOnDetection ?? true;
  }

  /**
   * Get the threshold
   */
  getThreshold(): number {
    return this.config.threshold ?? 0.8;
  }
}