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TracingChannel.prototype.tracePromise - diagnostics_channel - Node documentation
method TracingChannel.prototype.tracePromise
Unstable

Usage in Deno

import { TracingChannel } from "node:diagnostics_channel";
TracingChannel.prototype.tracePromise<
ThisArg = any,
Args extends any[] = any[],
>
(
fn: (
this: ThisArg,
...args: Args,
) => Promise<any>
,
context?: ContextType,
thisArg?: ThisArg,
...args: Args,
): void

Trace a promise-returning function call. This will always produce a start event and end event around the synchronous portion of the function execution, and will produce an asyncStart event and asyncEnd event when a promise continuation is reached. It may also produce an error event if the given function throws an error or the returned promise rejects. This will run the given function using channel.runStores(context, ...) on the start channel which ensures all events should have any bound stores set to match this trace context.

To ensure only correct trace graphs are formed, events will only be published if subscribers are present prior to starting the trace. Subscriptions which are added after the trace begins will not receive future events from that trace, only future traces will be seen.

import diagnostics_channel from 'node:diagnostics_channel';

const channels = diagnostics_channel.tracingChannel('my-channel');

channels.tracePromise(async () => {
  // Do something
}, {
  some: 'thing',
});

Type Parameters

ThisArg = any
Args extends any[] = any[]

Parameters

fn: (
this: ThisArg,
...args: Args,
) => Promise<any>

Promise-returning function to wrap a trace around

optional
context: ContextType

Shared object to correlate trace events through

optional
thisArg: ThisArg

The receiver to be used for the function call

...args: Args

Return Type

void

Chained from promise returned by the given function