/** @module trace */
import { IContext } from 'pip-services4-components-node';
import { TraceTiming } from './TraceTiming';
import { ITracer } from './ITracer';
/**
 * Dummy implementation of tracer that doesn't do anything.
 *
 * It can be used in testing or in situations when tracing is required
 * but shall be disabled.
 *
 * @see [[ITracer]]
 */
export declare class NullTracer implements ITracer {
    /**
     * Creates a new instance of the tracer.
     */
    NullTracer(): void;
    /**
     * Records an operation trace with its name and duration
     *
     * @param context     (optional) a context to trace execution through call chain.
     * @param component         a name of called component
     * @param operation         a name of the executed operation.
     * @param duration          execution duration in milliseconds.
     */
    trace(context: IContext, component: string, operation: string, duration: number): void;
    /**
     * Records an operation failure with its name, duration and error
     *
     * @param context     (optional) a context to trace execution through call chain.
     * @param component         a name of called component
     * @param operation         a name of the executed operation.
     * @param error             an error object associated with this trace.
     * @param duration          execution duration in milliseconds.
     */
    failure(context: IContext, component: string, operation: string, error: Error, duration: number): void;
    /**
     * Begings recording an operation trace
     *
     * @param context     (optional) a context to trace execution through call chain.
     * @param component         a name of called component
     * @param operation         a name of the executed operation.
     * @returns                 a trace timing object.
     */
    beginTrace(context: IContext, component: string, operation: string): TraceTiming;
}