Breadcrumbs
Sentry uses breadcrumbs to create a trail of events that happened prior to an issue. These events are very similar to traditional logs, but can record more rich structured data.
This page provides an overview of manual breadcrumb recording and customization. Learn more about the information that displays on the Issue Details page and how you can filter breadcrumbs to quickly resolve issues in Using Breadcrumbs.
Learn about SDK usage
Developers who want to modify the breadcrumbs interface can read about this in detail using the developer documentation devoted to the Breadcrumbs Interface.
Manual Breadcrumbs
You can manually add breadcrumbs whenever something interesting happens. For example, you might manually record a breadcrumb if the user authenticates or another state change happens.
import io.sentry.Breadcrumb;
import io.sentry.Sentry;
import io.sentry.SentryLevel;
Sentry.configureScope(scope -> {
Breadcrumb breadcrumb = new Breadcrumb();
breadcrumb.setCategory("auth");
breadcrumb.setMessage("Authenticated user " + user.getEmail());
breadcrumb.setLevel(SentryLevel.INFO);
scope.addBreadcrumb(breadcrumb);
});Automatic Breadcrumbs
SDKs will automatically start recording breadcrumbs by enabling integrations. For instance, the browser JavaScript SDK will automatically record all location changes.
Customize Breadcrumbs
SDKs customize breadcrumbs through the before_breadcrumb hook. This hook passes an already assembled breadcrumb and, in some SDKs, an optional
hint. The function can modify the breadcrumb or decide to discard it entirely:
For information about what can be done with the hint see Filtering Events.
import io.sentry.Sentry;
Sentry.init(options -> {
options.setBeforeBreadcrumb((breadcrumb, hint) -> {
if ("a.spammy.Logger".equals(breadcrumb.getCategory())) {
return null;
} else {
return breadcrumb;
}
});
});