Filter out bots

Third-parties bots can skew your experiment results by crawling your website and triggering events you only want to count for "real" visitors. Optimizely Feature Experimentation can solve this for you by filtering out bots on the IAB/ABC blacklist. Include the user agent for an event when you send that event to Optimizely.

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Note

Bot filtering does not apply to past bot events, so it is best to configure it before you start the experiment. Otherwise, if you enable filtering halfway through an experiment, you might have to discard (or export and manually filter) any bot-contaminated event data from the start of the experiment.

Enable bot filtering

Go to Settings > Advanced > Bot Filtering in the Optimizely Feature Experimentation app to toggle bot filtering on or off.

For information on how Optimizely filters bots, see Filter bots and spiders.

Client-side JavaScript events

No additional JavaScript code is required to enable bot filtering for events sent from browsers. When you track an event by calling the JavaScript SDK’s Track Event method, the SDK automatically includes the user’s user agent in the outbound request. If bot filtering is enabled for your project, Optimizely Feature Experimentation applies bot filtering automatically.

All other events

When you track events with an SDK from somewhere other than a web browser, you must pass the user agent to the user context so it can be filtered with your event. You should pass it using the reserved $opt_user_agent attribute in user-based methods. If bot filtering is enabled for your project and the user agent is passed in this way, Optimizely Feature Experimentation applies bot filtering.

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Important

Before implementing the $opt_user_agent attribute, Enable bot filtering in Optimizely first.

The example below shows how to pass the $opt_user_agent attribute.

// Get the user agent and pass it to the Optimizely  user context 
// as the attribute $opt_user_agent

let user_agent = "this_could_be_a_bot"

let attributes = ["device"          : "iphone",
                  "location"        : "Chicago",
                  "$opt_user_agent" : "this_could_be_a_bot"]

user = optimizely.createUserContext(userId: "test-user-id", attributes: attributes)

// now any user-based call filters out the bot
let decision = user.decide(key: "flag_1")
try? user.trackEvent(eventKey: "my_purchase_event_key")

The example below shows how to pass the $opt_user_agent attribute.

// Get the user agent and pass it to the Optimizely  user context 
// as the attribute $opt_user_agent

let user_agent = "this_could_be_a_bot"

let attributes = ["device"          : "iphone",
                  "location"        : "Chicago",
                  "$opt_user_agent" : "this_could_be_a_bot"]

user = optimizely.createUserContext(userId: "test-user-id", attributes: attributes)

// now any user-based call filters out the bot
let decision = user.decide(key: "flag_1")
try? user.trackEvent(eventKey: "my_purchase_event_key")