import { type HealthIndicatorResult } from './';
/**
 * A health indicator function for a health check
 *
 * @publicApi
 */
export type HealthIndicatorFunction = () => PromiseLike<HealthIndicatorResult> | HealthIndicatorResult;
/**
 * Represents an abstract health indicator
 * with common functionalities
 *
 * A custom HealthIndicator should inherit the `HealthIndicator` class.
 *
 * ```typescript
 *
 * class MyHealthIndicator extends HealthIndicator {
 *   public check(key: string) {
 *     // Replace with the actual check
 *     const isHealthy = true;
 *     // Returns { [key]: { status: 'up', message: 'Up and running' } }
 *     return super.getStatus(key, isHealthy, { message: 'Up and running' });
 *   }
 * }
 * ```
 *
 * @publicApi
 */
export declare abstract class HealthIndicator {
    /**
     * Generates the health indicator result object
     * @param key The key which will be used as key for the result object
     * @param isHealthy Whether the health indicator is healthy
     * @param data Additional data which will get appended to the result object
     */
    protected getStatus(key: string, isHealthy: boolean, data?: {
        [key: string]: any;
    }): HealthIndicatorResult;
}