Breadcrumbs Interface

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 technical information about a breadcrumb structure. You can read an overview of manual breadcrumb recording and customization on our Breadcrumbs Sentry docs page.

An event may contain a breadcrumbs property with one entry, values, which is an array of breadcrumb objects. The entries are ordered from oldest to newest. Consequently, the last entry in the list should be the last entry before the event occurred. Alternatively, the breadcrumbs property may be an array of breadcrumb objects by itself.

The following example illustrates the breadcrumbs part of the event payload and omits other attributes for simplicity.

{
  "breadcrumbs": {
    "values": [
      {
        "timestamp": "2016-04-20T20:55:53.845Z",
        "message": "Something happened",
        "category": "log",
        "data": {
          "foo": "bar",
          "blub": "blah"
        }
      },
      {
        "timestamp": "2016-04-20T20:55:53.847Z",
        "type": "navigation",
        "data": {
          "from": "/login",
          "to": "/dashboard"
        }
      }
    ]
  }
}

Or, alternatively:

{
  "breadcrumbs": [
    {
      "timestamp": "2016-04-20T20:55:53.845Z",
      "message": "Something happened",
      "category": "log",
      "data": {
        "foo": "bar",
        "blub": "blah"
      }
    },
    {
      "timestamp": "2016-04-20T20:55:53.847Z",
      "type": "navigation",
      "data": {
        "from": "/login",
        "to": "/dashboard"
      }
    }
  ]
}

A breadcrumb object has the following properties:

type (optional)

The type of breadcrumb. By default, all breadcrumbs are recorded as default, which makes them appear as a Debug entry, but Sentry provides other types that influence how the breadcrumbs are rendered. For more information, see the description of recognized breadcrumb types.

category (optional)

A dotted string indicating what the crumb is or from where it comes. Typically it is a module name or a descriptive string. For instance, ui.click could be used to indicate that a click happened in the UI or flask could be used to indicate that the event originated in the Flask framework.

Internally we render some crumbs' color and icon based on the provided category. For more information, see the description of recognized breadcrumb types.

message (optional)

Human-readable message for the breadcrumb.

If a message is provided, it is rendered as text with all whitespace preserved.

data (optional)

Arbitrary data associated with this breadcrumb.

Contains a dictionary whose contents depend on the breadcrumb type. Additional parameters that are unsupported by the type are rendered as a key/value table.

level (optional)

This defines the severity level of the breadcrumb. Allowed values are, from highest to lowest: fatal, error, warning, info, and debug. Levels are used in the UI to emphasize and deemphasize the crumb. The default is info.

origin (optional)

A string representing the origin of the breadcrumb. This is typically used to identify the source of the breadcrumb. For example hybrid SDKs can identify native breadcrumbs from JS or Flutter.

timestamp (recommended)

A timestamp representing when the breadcrumb occurred. The format is either a string as defined in RFC 3339 or a numeric (integer or float) value representing the number of seconds that have elapsed since the Unixepoch.

Breadcrumbs are most useful when they include a timestamp, as it creates a timeline leading up to an event expection/error.

Breadcrumb Types

Below are descriptions of individual breadcrumb types, and what their data properties look like.

default

Describes a generic breadcrumb. This is typically a log message or user-generated breadcrumb. The data part is entirely undefined and as such, completely rendered as a key/value table.

{
  "type": "default",
  "category": "started",
  "data": undefined,
  "level": "info",
  "message": "this is a message",
  "timestamp": 1596814007.035
}

debug

This is typically a log message. The data part is entirely undefined and as such, completely rendered as a key/value table.

Internally we display breadcrumbs of type default that contain category console as a breadcrumb of type debug.

{
  "type": "debug",
  "category": "started",
  "data": null,
  "level": "info",
  "message": "this is a message",
  "timestamp": 1596814007.035
}

error

An error that occurred before the exception.

{
  "type": "error",
  "category": "error",
  "level": "error",
  "message": "this is a message",
  "timestamp": 1596814007.035
}

navigation

A navigation event can be a URL change in a web application, or a UI transition in a mobile or desktop application, etc.

Internally we display breadcrumbs of type default that contain category navigation as a breadcrumb of type navigation.

Its data property has the following sub-properties:

from (Required)

A string representing the original application state / location.

to (Required)

A string representing the new application state / location.

{
  "type": "navigation",
  "category": "navigation",
  "timestamp": "2016-04-20T20:55:53.845Z",
  "data": {
    "from": "/login",
    "to": "/dashboard"
  }
}

http

This represents an HTTP request transmitted from your application. This could be an AJAX request from a web application, or a server-to-server HTTP request to an API service provider, etc.

Its data property has the following sub-properties:

url (optional)

The request URL.

method (optional)

The HTTP request method.

status_code (optional)

The HTTP status code of the response.

reason (optional)

Text that describes the status code.

{
  "type": "http",
  "category": "xhr",
  "data": {
    "url": "http://example.com/api/1.0/users",
    "method": "GET",
    "status_code": 200,
    "reason": "OK"
  },
  "timestamp": "2016-04-20T20:55:53.845Z"
}

info

Information that helps identify the root cause of the issue or for whom the error occurred.

{
  "type": "info",
  "category": "started",
  "level": "info",
  "message": "this is a message",
  "timestamp": 1596813998.386
}

query

This represents a query that was made in your application.

{
  "type": "query",
  "category": "started",
  "level": "info",
  "message": "this is a message",
  "timestamp": 1596813998.386
}

transaction

Describes a tracing event.

Internally we display breadcrumbs of type default that contain categories sentry.transaction and sentry.event as a breadcrumb of type transaction.

{
  "type": "default",
  "category": "sentry.transaction",
  "level": "info",
  "message": "this is a message",
  "timestamp": 1596813997.646
}

ui

A user interaction with your app's UI.

Internally, we display breadcrumbs of type default that contain category ui.* as a breadcrumb of type ui.

{
  "type": "default",
  "category": "ui.click",
  "message": "div.css-bsbdc4-TextOverflow.e1kpcezi0",
  "level": "info",
  "timestamp": 1598613151.875368
}

user

A user interaction with your app's UI.

{
  "type": "user",
  "category": "click",
  "message": "div.css-bsbdc4-TextOverflow.e1kpcezi0",
  "level": "info",
  "timestamp": 1598613151.875368
}