Set Up Metrics
Metrics allow you to send, view and query counters, gauges and measurements from your Sentry-configured apps to track application health and drill down into related traces, logs, and errors.
With Sentry Metrics, you can send counters, gauges, and distributions from your applications to Sentry. Once in Sentry, these metrics can be viewed alongside relevant errors, and searched using their individual attributes.
This feature is currently in open beta. Features in beta are still in progress and may have bugs.
Metrics are supported in Sentry Flutter SDK version 9.11.0 and above.
| Type | Use For |
|---|---|
count | Events (orders, clicks, API calls) |
gauge | Current values (queue depth, connections) |
distribution | Value ranges (response times, payload sizes) |
No setup required beyond SDK initialization.
import 'package:sentry_flutter/sentry_flutter.dart';
// Count occurrences
Sentry.metrics.count('orders_created', 1);
// Track current values
Sentry.metrics.gauge('active_connections', 42);
// Track distributions
Sentry.metrics.distribution(
'api_latency',
187,
unit: 'millisecond',
);
Attributes let you filter and group metrics in Sentry. Use them for:
- Environment segmentation
- Feature flag tracking
- User tier analysis
Each metric has a 2KB size limit. If you exceed this, the metric will be dropped.
Sentry.metrics.count(
'api_calls',
1,
attributes: {
'endpoint': SentryAttribute.string('/api/orders'),
'user_tier': SentryAttribute.string('pro'),
'region': SentryAttribute.string('us-west'),
},
);
Use scope APIs to set attributes that apply to all metrics while the scope is active.
// Add attributes to the global scope
Sentry.setAttributes({'is_admin': SentryAttribute.bool(true)});
// All scope attributes are added to metrics
Sentry.metrics.count('clicks', 1);
Sentry.metrics.gauge(
'time_since_refresh',
4,
unit: 'second',
);
For gauge and distribution metrics, specify a unit to help Sentry display values in a human-readable format.
Common units: millisecond, second, byte, kilobyte, megabyte. Use SentryMetricUnit to conveniently access supported units in Dart. See supported units for the full list.
Sentry.metrics.distribution(
'response_time',
187.5,
unit: SentryMetricUnit.millisecond,
);
Sentry.metrics.gauge(
'memory_usage',
1024,
unit: SentryMetricUnit.byte,
);
Filter or modify metrics before sending. Return null to drop a metric.
import 'package:sentry_flutter/sentry_flutter.dart';
await SentryFlutter.init((options) {
options.dsn = '___PUBLIC_DSN___';
options.beforeSendMetric = (metric) {
// Drop specific metrics
if (metric.attributes.containsKey('debug')) {
return null;
}
// Return the metric to send it
return metric;
};
});
Set enableMetrics: false to disable metrics collection entirely.
import 'package:sentry_flutter/sentry_flutter.dart';
await SentryFlutter.init((options) {
options.dsn = '___PUBLIC_DSN___';
options.enableMetrics = false;
});
Sentry automatically attaches these attributes to every metric:
| Attribute | Description | Context |
|---|---|---|
sentry.environment | Environment from SDK config | Always |
sentry.release | Release version from SDK config | Always |
sentry.sdk.name | SDK name | Always |
sentry.sdk.version | SDK version | Always |
os.name | Operating system name | If available |
os.version | Operating system version | If available |
device.brand | Device manufacturer | If available |
device.model | Device model name | If available |
device.family | Device family | If available |
user.id, user.name, user.email | User identifiers | If sendDefaultPii enabled |
sentry.replay_id | Session replay ID | If replay available |
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").