Correlate Logs with Traces

A common use case for the Trace Search tool is to see the related trace while inspecting a log event. To do this, you must attach an active traceId to your logs.
Setup
Follow these steps to attach traceId to your logs.
Use the getContext method, exposed from our package:
const { getContext } = require('@aspecto/opentelemetry');
​
console.log('Something happened!', { traceId: getContext().traceId });
If you're using a custom logger, we recommend you add the traceId to all logs by default.
Here's an example using winston:
const { getContext } = require('@aspecto/opentelemetry');
const winston = require('winston');
​
const addAspectoTraceId = winston.format((info) => {
  info.traceId = getContext().traceId;
  return info;
});
​
const logger = winston.createLogger({
  format: winston.format.combine(
    addAspectoTraceId(), 
    winston.format.json()
  ),
  transports: [ ... ],
});
Sampled Flag
Some traces may be unsampled due to sampling rules or  the samplingRatio SDK setting.
In those cases, you may want to reflect this on your log, so later on, you'd be able to know whether to expect to see the matching trace on Aspecto, or not.

For this, the getContext() response payload will also contain a boolean called sampled, reflecting the sampling result.
Use
After completing the setup, and deploying your service, find the relevant log in your logging solution (e.g., CloudWatch, logz.io, etc...) and copy the traceId.
Finding the traceId in a CloudWatch log
Next, go to Trace Search and search for the traceId you just copied:
Searching for traceId in Trace Search
Then, visualize and debug the trace.

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Last modified 10mo ago

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Outline

Setup

Sampled Flag

Use