RUM Flutter Advanced Configuration

Overview

If you have not set up the Datadog Flutter SDK for RUM yet, follow the in-app setup instructions or refer to the RUM Flutter setup documentation.

Enrich user sessions

Flutter RUM automatically tracks attributes such as user activity, views (using the DatadogNavigationObserver), errors, native crashes, and network requests (using the Datadog Tracking HTTP Client). See the RUM Data Collection documentation to learn about the RUM events and default attributes. You can further enrich user session information and gain finer control over the attributes collected by tracking custom events.

Add your own performance timing

In addition to RUM’s default attributes, you can measure where your application is spending its time by using DdRum.addTiming. The timing measure is relative to the start of the current RUM view.

For example, you can time how long it takes for your hero image to appear:

void _onHeroImageLoaded() {
    DatadogSdk.instance.rum?.addTiming("hero_image");
} 

Once you set the timing, it is accessible as @view.custom_timings.<timing_name>. For example, @view.custom_timings.hero_image.

To create visualizations in your dashboards, create a measure first.

Track user actions

You can track specific user actions such as taps, clicks, and scrolls using DdRum.addUserAction.

To manually register instantaneous RUM actions such as RumUserActionType.tap, use DdRum.addUserAction(). For continuous RUM actions such as RumUserActionType.scroll, use DdRum.startUserAction() or DdRum.stopUserAction().

For example:

void _downloadResourceTapped(String resourceName) {
    DatadogSdk.instance.rum?.addUserAction(
        RumUserActionType.tap,
        resourceName,
    );
}

When using DdRum.startUserAction and DdRum.stopUserAction, the type action must be the same in order for the Datadog Flutter SDK to match an action’s start with its completion.

Track custom resources

In addition to tracking resources automatically using the Datadog Tracking HTTP Client, you can track specific custom resources such as network requests or third-party provider APIs using the following methods:

  • DdRum.startResourceLoading
  • DdRum.stopResourceLoading
  • DdRum.stopResourceLoadingWithError
  • DdRum.stopResourceLoadingWithErrorInfo

For example:

// in your network client:

DatadogSdk.instance.rum?.startResourceLoading(
    "resource-key", 
    RumHttpMethod.get,
    url,
);

// Later

DatadogSdk.instance.rum?.stopResourceLoading(
    "resource-key",
    200,
    RumResourceType.image
);

The String used for resourceKey in both calls must be unique for the resource you are calling in order for the Flutter Datadog SDK to match a resource’s start with its completion.

Track custom errors

To track specific errors, notify DdRum when an error occurs with the message, source, exception, and additional attributes.

DatadogSdk.instance.rum?.addError("This is an error message.");

Track custom global attributes

In addition to the default RUM attributes captured by the Datadog Flutter SDK automatically, you can choose to add additional contextual information (such as custom attributes) to your RUM events to enrich your observability within Datadog.

Custom attributes allow you to filter and group information about observed user behavior (such as the cart value, merchant tier, or ad campaign) with code-level information (such as backend services, session timeline, error logs, and network health).

Set a custom global attribute

To set a custom global attribute, use DdRum.addAttribute.

  • To add or update an attribute, use DdRum.addAttribute.
  • To remove the key, use DdRum.removeAttribute.

Track user sessions

Adding user information to your RUM sessions makes it easy to:

  • Follow the journey of a given user
  • Know which users are the most impacted by errors
  • Monitor performance for your most important users
User API in the RUM UI

The following attributes are optional, provide at least one of them:

AttributeTypeDescription
usr.idStringUnique user identifier.
usr.nameStringUser friendly name, displayed by default in the RUM UI.
usr.emailStringUser email, displayed in the RUM UI if the user name is not present. It is also used to fetch Gravatars.

To identify user sessions, use DdRum.setUserInfo.

For example:

DatadogSdk.instance.setUserInfo("1234", "John Doe", "john@doe.com");

Modify or drop RUM events

To modify attributes of a RUM event before it is sent to Datadog or to drop an event entirely, use the Event Mappers API when configuring the Flutter RUM SDK:

final config = DdSdkConfiguration(
    // other configuration...
    rumConfiguration: RumConfiguration(
        applicationId: '<YOUR_APPLICATION_ID>',
        rumViewEventMapper = (event) => event,
        rumActionEventMapper = (event) => event,
        rumResourceEventMapper = (event) => event,
        rumErrorEventMapper = (event) => event,
        rumLongTaskEventMapper = (event) => event,
    ),
);

Each mapper is a function with a signature of (T) -> T?, where T is a concrete RUM event type. This allows changing portions of the event before it is sent, or dropping the event entirely.

For example, to redact sensitive information in a RUM Resource’s url, implement a custom redacted function and use it in rumResourceEventMapper:

    rumResourceEventMapper = (event) { 
        var resourceEvent = resourceEvent
        resourceEvent.resource.url = redacted(resourceEvent.resource.url)
        return resourceEvent
    }
}

Returning null from the error, resource, or action mapper drops the event entirely; the event is not sent to Datadog. The value returned from the view event mapper must not be null.

Depending on the event’s type, only some specific properties can be modified:

Event TypeAttribute keyDescription
RumViewEventviewEvent.view.nameName of the view.
viewEvent.view.urlURL of the view.
viewEvent.view.referrerReferrer of the view.
RumActionEventactionEvent.action.target?.nameName of the action.
actionEvent.view.nameName the view linked to this action.
actionEvent.view.referrerReferrer of the view linked to this action.
actionEvent.view.urlURL of the view linked to this action.
RumErrorEventerrorEvent.error.messageError message.
errorEvent.error.stackStacktrace of the error.
errorEvent.error.resource?.urlURL of the resource the error refers to.
errorEvent.view.nameName the view linked to this action.
errorEvent.view.referrerReferrer of the view linked to this action.
errorEvent.view.urlURL of the view linked to this error.
RumResourceEventresourceEvent.resource.urlURL of the resource.
resourceEvent.view.nameName the view linked to this action.
resourceEvent.view.referrerReferrer of the view linked to this action.
resourceEvent.view.urlURL of the view linked to this resource.

In order to be compliant with data protection and privacy policies, the Flutter RUM SDK requires the tracking consent value at initialization.

The trackingConsent setting can be one of the following values:

  1. TrackingConsent.pending: The Flutter RUM SDK starts collecting and batching the data but does not send it to Datadog. The Flutter RUM SDK waits for the new tracking consent value to decide what to do with the batched data.
  2. TrackingConsent.granted: The Flutter RUM SDK starts collecting the data and sends it to Datadog.
  3. TrackingConsent.notGranted: The Flutter RUM SDK does not collect any data. No logs, traces, or RUM events are sent to Datadog.

To change the tracking consent value after the Flutter RUM SDK is initialized, use the DatadogSdk.setTrackingConsent API call. The Flutter RUM SDK changes its behavior according to the new value.

For example, if the current tracking consent is TrackingConsent.pending and you change the value to TrackingConsent.granted, the Flutter RUM SDK sends all previously recorded and future data to Datadog.

Likewise, if you change the value from TrackingConsent.pending to TrackingConsent.notGranted, the Flutter RUM SDK wipes all data and does not collect any future data.

Sample RUM sessions

To control the data your application sends to Datadog RUM, you can specify a sampling rate for RUM sessions while initializing the Flutter RUM SDK as a percentage between 0 and 100.

For example, to keep only 50% of sessions, use:

final config = DdSdkConfiguration(
    // other configuration...
    rumConfiguration: RumConfiguration(
        applicationId: '<YOUR_APPLICATION_ID>',
        sessionSamplingRate: 50.0,
    ),
);

Sending data when device is offline

RUM ensures availability of data when your user device is offline. In cases of low-network areas, or when the device battery is too low, all RUM events are first stored on the local device in batches. They are sent as soon as the network is available, and the battery is high enough to ensure the Flutter RUM SDK does not impact the end user’s experience. If the network is not available with your application running in the foreground, or if an upload of data fails, the batch is kept until it can be sent successfully.

This means that even if users open your application while offline, no data is lost.

Note: The data on the disk is automatically deleted if it gets too old to ensure the Flutter RUM SDK does not use too much disk space.

Further reading

Additional helpful documentation, links, and articles: