Node.jsSet Up Metrics
Metrics for JavaScript are supported with Sentry JavaScript SDK version 7.103.0 and above.
Sentry metrics help you pinpoint and solve issues that impact user experience and app performance by measuring the data points that are important to you. You can track things like processing time, event size, user signups, and conversion rates, then correlate them back to tracing data in order to get deeper insights and solve issues faster.
To configure metrics, add the metricsAggregator experimental option to your Sentry.init call.
Sentry.init({
dsn: 'https://examplePublicKey@o0.ingest.sentry.io/0',
_experiments: {
metricsAggregator: true,
},
});
Counters are one of the more basic types of metrics and can be used to count certain event occurrences.
To emit a counter, do the following:
// Increment a counter by one for each button click.
Sentry.metrics.increment("button_click", 1, {
tags: { browser: "Firefox", app_version: "1.0.0" },
});
Distributions help you get the most insights from your data by allowing you to obtain aggregations such as p90, min, max, and avg.
To emit a distribution, do the following:
// Add '15.0' to a distribution used for tracking the loading times for component.
Sentry.metrics.distribution("component_load_time", 15.0, {
tags: { type: "important" },
unit: "millisecond",
});
Sets are useful for looking at unique occurrences and counting the unique elements you added.
To emit a set, do the following:
// Add 'jane' to a set used for tracking the number of users that viewed a page.
Sentry.metrics.set("user_view", "jane");
Gauges let you obtain aggregates like min, max, avg, sum, and count. They can be represented in a more space-efficient way than distributions, but they can't be used to get percentiles. If percentiles aren't important to you, we recommend using gauges.
To emit a gauge, do the following:
// Add 2 to a gauge tracking CPU usage.
Sentry.metrics.gauge("cpu_usage", 34, {
tags: { os: "MacOS" },
unit: "percent",
});
You can pass a unit as a optional parameter of the third argument of the increment, distribution, set, and gauge methods.
Units augment metric values by giving meaning to what otherwise might be abstract numbers. Adding units also allows Sentry to offer controls - unit conversions, filters, and so on - based on those units. For values that are unitless, you can supply an empty string or none.
These following units are understood by the Sentry backend, but you can supply any arbitrary units you want.
nanosecondmicrosecondmillisecondsecondminutehourdayweek
bitbytekilobytekibibytemegabytemebibytegigabytegibibyteterabytetebibytepetabytepebibyteexabyteexbibyte
ratiopercent
If you want to explore further, you can find details about supported units in our event ingestion documentation.
Our documentation is open source and available on GitHub. Your contributions are welcome, whether fixing a typo (drat!) or suggesting an update ("yeah, this would be better").
