Add a listener - Optimizely for Web

Listen to a snippet lifecycle event.

addListener

Syntax

window["optimizely"].push(addListener);

Parameters

Parameter and Type	Child Attribute	Description
`addListener` AddListenerObject		An object with the `type` field set to `addListener`. The other fields are the function arguments. Required.
`type` string	Child attribute of type AddListenerObject	The argument indicating that you are using the `addListener` function. Required.
`filter` FilterObject	Child attribute of type AddListenerObject	By setting a filter, you can define the type of events or category of events the handler is called for.
`type` string Required	Child attribute of type FilterObject	The category of an event. Possible values: `lifecycle` and `analytics`. Required.
`name` string	Child attribute of type FilterObject	The name of the event type. The value can be `initialized`, `applied`, `activated`, `campaignDecided`, `pageActivated`, `pageDeactivated`, `originsSynced`, or `trackEvent`.
`handler` function	Child attribute of type AddListenerObject	The function that will be called when the event occurs.

Example Call

window["optimizely"].push({
  "type": "addListener",
  "filter": {
    "type": "lifecycle",
    "name": "initialized"
  },
  "handler": function(event) {
    console.log("Project " + window["optimizely"].get("data").projectId + " is initialized");
  }
});

Description

Listen to a specific event from somewhere in the snippet's execution. For example, you can listen to the initialized event if you want to use the window.optimizely.get APIs as soon as they become available, or you can listen to the pageActivated event if you want to run code every time a page activates.

Your handler function will be invoked for each applicable lifecycle event that occurs after the handler is registered. It is not retroactively invoked for events that may have occurred prior to handler registration.

You can listen to the following types of events:

initialized

Fires once the JavaScript API has been initialized.

Syntax

var initialized = function(initialized);

Parameters

Parameter and Type	Child Attribute	Description
`initialized` InitializedObject		This is the object passed to the handler function. Required.
`type` string	Child attribute of type InitializedObject	The category of an event. The value will be lifecycle for this event. Required.
`name` string	Child attribute of type InitializedObject	The name of the event type. This is set to initialized.

Example Call

function onInitialized(event) {
  console.log("Project " + window["optimizely"].get("data").projectId + " is initialized");
}

window["optimizely"] = window["optimizely"] || [];
window["optimizely"].push({
  type: "addListener",
  filter: {
    type: "lifecycle",
    name: "initialized"
  },
  handler: onInitialized
});

Description

By this point, the Optimizely snippet will have processed all window.optimizely.push API calls that were made before the snippet began to execute or during Project JavaScript.

window.optimizely.get will now be defined in addition to window.optimizely.push, although visitor-specific state data (such as that returned by get('visitor') and get('state').getCampaignStates()) may not have been determined yet.

The snippet only initializes once per browser page load.

action.applied

Fires when some action (set of changes) has been applied.

Syntax

var actionApplied = function(actionAppliedEvent);

Parameters

Parameter and Type	Child Attribute	Description
`actionAppliedEvent` ActionAppliedEvent		The data relevant to the action.applied event. Required.
`type` string	Child attribute of type ActionAppliedEvent	The type of the event. Always "action" for this event. Required.
`name` string	Child attribute of type ActionAppliedEvent	The name of the event. Always "applied" for this event. Required.
`data` ActionAppliedEventData	Child attribute of type ActionAppliedEvent	Data about the event. Required.
`changes` array[ChangeData]	Child attribute of type array[ChangeData]	List of changes that were attempted.
`type` string	Child attribute of type ChangeData	Type of the change (e.g., "attribute", "code").
`selector` string or undefined	Child attribute of type ChangeData	(For visual element-based changes only) Selector chosen in the editor.
`attributes` object or undefined	Child attribute of type ChangeData	Change-specific attributes, such as the HTML attribute to modify, and the modified value.
`type` string or function or undefined	Child attribute of type ChangeData	String value for "insert_html", "insert_image", and "custom_css". Function to execute if "custom_code".
`campaignId` string	Child attribute of type ActionAppliedEvent	ID of campaign the action belongs to. Required.
`pageId` string	Child attribute of type ActionAppliedEvent	ID of the page on which the action was executed. Required.
`experimentId` string or undefined	Child attribute of type ActionAppliedEvent	ID of experiment the action belongs to, or undefined if campaign action.
`variationId` string or undefined	Child attribute of type ActionAppliedEvent	ID of variation the action belongs to, or undefined if campaign or experiment action.

Example Call

function onActionApplied(event) {
  console.log("Applied action for Campaign:", event.data.campaignId);
}

window.optimizely.push({
  "type": "addListener",
  "filter": {
    "type": "action",
    "name": "applied"
  },
  "handler": onActionApplied
});

Description

After the Optimizely snippet has decided on a variation for a particular campaign or experiment, it delivers the experience as a set of "actions". Each action is specific to a variation (for most changes) or experiment (for Shared Code and Shared CSS), and may be specific to a page.

Use this lifecycle event to detect when actions have been applied. Your handler can inspect the event payload to distinguish between the various actions that may be applied during the current page load.

Note: The snippet may reapply an action's changes after the corresponding lifecycle event has fired, if elements relevant to a particular change appear at different times rather than all at once. This is particularly likely if you're using Optimizely on a dynamic website.

activated

Fires each time the Optimizely snippet activates.

Syntax

var activated = function(activated);

Parameters

Parameter and Type	Child Attribute	Description
`activated` ActivatedObject		This is the object passed to the handler function. Required.
`type` string	Child attribute of type ActivatedObject	The category of an event. The value will be lifecycle for this event. Required.
`name` string	Child attribute of type ActivatedObject	The name of the event type. This is set to activated.

Example Call

function onActivated(event) {
  var visitorId = window.optimizely.get('visitor_id').randomId;
  console.log("The visitor's ID is: " + visitorId);
}

window["optimizely"] = window["optimizely"] || [];
window["optimizely"].push({
  type: "addListener",
  filter: {
    type: "lifecycle",
    name: "activated"
  },
  handler: onActivated
});

Description

At this point, the Optimizely snippet has been activated, and you can query query for visitor state such as:

Visitor ID.
Page states. A page will be marked isActive if it was synchronously triggered
by:
- an immediate trigger.
- a URL change or DOM change trigger. (These triggers fire immediately during snippet activation, not just when the URL or DOM changes.)
- a callback trigger, if its conditional activation code synchronously invokes the callback.
- a manual trigger, if the corresponding JavaScript API was called before snippet activation and was found to have passing conditions.
Campaign states and experiment states, for campaigns and experiments that
1. specify changes to active Pages (see above), and
2. target audiences that the snippet was able to evaluate using data it already had on hand, without waiting for the browser to download additional data.

The snippet activates immediately upon snippet initialization, but will also reactivate each time the activate API is called.

campaignDecided

Fires each time the visitor is assigned a variation (or none) for a campaign or experiment.

Syntax

var campaignDecided = function(campaignDecided);

Parameters

Parameter and Type	Child Attribute	Description
`campaignDecided` CampaignDecidedObject		The data relevant to the campaignDecided event. Required.
`type` string	Child attribute of type CampaignDecidedObject	The category of an event. The value will be lifecycle for this event. Required.
`name` string	Child attribute of type CampaignDecidedObject	The name of the event type. This is set to campaignDecided.
`data` CampaignEventData	Child attribute of type CampaignDecidedObject	Data associated to this event. You can use this object to determine which campaign a decision was made for.
`campaign` Campaign	Child attribute of type CampaignEventData	The complete campaign object.
`changes` array[Change]	Child attribute of type Campaign	Changes on a campaign level. These changes are executed every time the campaign gets activated, regardless of the experiment and variation a visitor is assigned to.
`` string* or integer	Child attribute of type Change	You can specify additional properties of your choice.
`commitId` string	Child attribute of type Campaign	A new "commit" is made every time a campaign is published. The commit ID refers to the commit that was made. Every time a campaign is published, the commit ID changes.
`experiments` array[Experiment]	Child attribute of type Campaign	An array of experiments within the campaign. For AB tests, there is always one experiment. Personalization Campaigns can have more experiments.
`audienceIds` array[string,array]	Child attribute of type Experiment	Representation of audience conditions for the experiment, including audience IDs and combinators. See audience_conditions for format.
`audienceName` string	Child attribute of type Experiment	Representation of name of audience(s) used in the experiment.
`id` string	Child attribute of type Experiment	The ID of the experiment.
`name` string	Child attribute of type Experiment	The name of the experiment.
`integrationSettings` IntegrationObject	Child attribute of type Experiment	An object that contains all the integration settings that are enabled for this experiment. Each key in the object is mapped to a particular integration.
`` string* or integer	Child attribute of type IntegrationObject	You can specify additional properties of your choice.
`variations` array[Variation]	Child attribute of type Experiment	The variations within an experiment. There are one or more variations in an experiment.
`actions` Action	Child attribute of type Variation	The actions that are executed once a visitor gets bucketed in this variation. The actions describe the variation.
`pageId` string	Child attribute of type Action	The ID of the page where the action will take place.
`changes` array[Change] or string	Child attribute of type Action	An array of changes that have been set up for this page.
`` string* or integer	Child attribute of type Change	You can specify additional properties of your choice.
`commitId` string	Child attribute of type Campaign	A new "commit" is made every time a campaign is published. The commit ID refers to the commit that was made. Every time a campaign is published, the commit ID changes.
`experiments` array[Experiment]	Child attribute of type Campaign	An array of experiments within the campaign. For AB tests, there is always one experiment. Personalization Campaigns can have more experiments.
`audienceIds` array[string,array]	Child attribute of type Experiment	Representation of audience conditions for the experiment, including Audience IDs and combinators. See audience_conditions for format.
`audienceName` string	Child attribute of type Experiment	Representation of name of audience(s) used in experiment.
`id` string	Child attribute of type Experiment	The ID of the experiment.
`name` string	Child attribute of type Experiment	The name of the experiment.
`integrationSettings` IntegrationObject	Child attribute of type Experiment	An object that contains all the integration settings that are enabled for this experiment. Each key in the object is mapped to a particular integration.
`` string* or integer	Child attribute of type IntegrationObject	You can specify additional properties of your choice.
`variations` array[Variation]	Child attribute of type Experiment	The variations within an experiment. There are one or more variations in an experiment.
`actions` Action	Child attribute of type Variation	The actions that are executed once a visitor gets bucketed in this variation. The actions describe the variation.
`pageId` string	Child attribute of type Action	The ID of the page where the action will take place.
`changes` array[Change]	Child attribute of type Action	An array of changes that have been set up for this page.
`` string* or integer	Child attribute of type Change	You can specify additional properties of your choice.
`id` string	Child attribute of type Variation	The ID of the variation.
`name` string	Child attribute of type Variation	The name of the variation.
`weightDistributions` null or array[WeightDistributionsObject]	Child attribute of type Experiment	Traffic allocation among the variations in the experiment.
`entityId` string	Child attribute of type WeightDistributionsObject	The ID of the variation that has the endOfRange value assigned to it.
`endOfRange` integer	Child attribute of type WeightDistributionsObject	Each object in the array has a endOfRange value. The endOfRange of the current object minus the endOfRange object of the previous object is the traffic allocation assigned to the variation. The last object in the array always has a endOfRange value of 10000.
`id` string	Child attribute of type Campaign	The ID of the campaign.
`name` string	Child attribute of type Campaign	The name of the campaign.
`holdback` integer	Child attribute of type Campaign	The holdback value on a campaign represents the percentage of visitors excluded from a campaign. If the holdback is set to 500, then 5% of all visitors are excluded from the campaign.
`policy` string	Child attribute of type Campaign	The policy of a campaign indicates if the campaign is an AB test or a Personalization campaign. The possible values are: "single_experiment": A normal AB test "random": A Personalization campaign
`integrationSettings` IntegrationObject	Child attribute of type Campaign	An object that contains all the integration settings that are enabled for this campaign.
`` string* or integer	Child attribute of type IntegrationObject	You can specify additional properties of your choice.
`pageIds` array[string]	Child attribute of type Campaign	An array with the IDs of all the pages that are used within the campaign.
`decisionTicket` DecisionTicketObject	Child attribute of type CampaignEventData	The decision ticket.
`audienceIds` array	Child attribute of type DecisionTicketObject	An array of audiences the visitor qualified for at the time of the decision.
`bucketingId` string	Child attribute of type DecisionTicketObject	Optimizely unique end user ID used to bucket the visitor.
`preferredVariationMap` object	Child attribute of type DecisionTicketObject	Contains a map of experiment ID to variation ID.
`decision` DecisionObject	Child attribute of type CampaignEventData	The decision for this campaign. Required.
`campaignId` string	Child attribute of type DecisionObject	The ID of the campaign the visitor is bucketed in.
`experimentId` string	Child attribute of type DecisionObject	The ID of the experiment the visitor is bucketed in (if any).
`isCampaignHoldback` Boolean	Child attribute of type DecisionObject	Property showing if a user has been included in the experiment based on the traffic allocation setting of the A/B experiment. For Personalization Campaigns, this property is based on the campaign holdback setting.
`variationId` string	Child attribute of type DecisionObject	The ID of the variation the visitor is bucketed in (if any).
`reason` string	Child attribute of type DecisionObject	The reason the visitor was not bucketed into a variation, e.g., "not eligible for any experiments".
`error` Error	Child attribute of type DecisionObject	Any uncaught error encountered in the process of evaluating the decision. This could be indicative of a problem and should be reported to Optimizely support.
`audiences` array[integer]	Child attribute of type CampaignEventData	The IDs of all the audiences in this campaign the visitor qualified for.

Example Call

function onCampaignDecided(event) {
  console.log("The visitor is now seeing variation " + event.data.decision.variationId + " of campaign " + event.data.campaign.name);
}

window["optimizely"] = window["optimizely"] || [];
window["optimizely"].push({
  type: "addListener",
  filter: {
    type: "lifecycle",
    name: "campaignDecided"
  },
  handler: onCampaignDecided
});

Description

Each time the Optimizely snippet activates a campaign or experiment, the snippet decides which variation (if any) to serve to the current visitor and then fires a campaignDecided event.

Any X Web events triggered by your handler function will attribute to the variation that the visitor has just been assigned to, in addition to previously served variations.

If you want to track decisions in an external analytics platform, we recommend that you create a custom analytics integration instead of using this API directly. Custom analytics integrations are easier to configure and, unlike this API, can be used to track redirect decisions.

pageActivated

Fires each time a page becomes active.

Syntax

var pageActivated = function(pageActivated);

Parameters

Parameter and Type	Child Attribute	Description
`pageActivated` PageActivatedObject		The data relevant to the pageActivated event. Required.
`type` string	Child attribute of type PageActivatedObject	The category of an event. The value will be `lifecycle` for this event. Required.
`name` string	Child attribute of type PageActivatedObject	The name of the event type. This is set to `pageActivated`.
`data` PageEventData	Child attribute of type PageActivatedObject	Data associated to this event. You can use this object to determine which page has been activated.
`page` Page	Child attribute of type PageEventData	The complete page object.
`activationType` string	Child attribute of type Page	The trigger type that activates the page.
`apiName` string	Child attribute of type Page	A machine-readable name for the page. The `apiName` value can be used in the page function to indicate which event has occurred.
`category` string	Child attribute of type Page	An event category that was selected upon creation of the page. Some valid values for category are "added to cart", "saved", "shared", "searched", "purchased", "converted", "signed up", "subscribed", "other".
`deactivationEnabled` Boolean	Child attribute of type Page	Whether or not this page is automatically deactivated when its trigger fires and conditions are false.
`id` string	Child attribute of type Page	The page ID.
`staticConditions` array	Child attribute of type Page	The conditions that need to be true for the page to be activated.
`undoOnDeactivation` Boolean	Child attribute of type Page	Whether or not the changes for this page are undone when this page deactivates. Note that not all types of changes can be undone. Learn more.
`tags` array[VisualTagObject]	Child attribute of type Page	An array of the visual tags saved on a page. Read more about visual tags.
`category` string	Child attribute of type VisualTagObject	A tag category that was selected upon creation of the tag. Some valid values for category are: "category", "subcategory", "title", "price", "other".
`locator` string	Child attribute of type VisualTagObject	The logic/CSS selector indicating where a tag is located on the page.
`apiName` string	Child attribute of type VisualTagObject	A machine-readable name for the tag.
`locatorType` string	Child attribute of type VisualTagObject	A enum that indicates if the locator is custom "javascript" or a "css_selector".

Example Call

function onPageActivated(event) {
  console.log("The Page " + event.data.page.name + " is now active");
}

window["optimizely"] = window["optimizely"] || [];
window["optimizely"].push({
  type: "addListener",
  filter: {
    type: "lifecycle",
    name: "pageActivated"
  },
  handler: onPageActivated
});

Description

This event indicates when a page has become active.

In some cases a page may activate during snippet activation, while in other cases activation may occur after snippet activation or not at all.

This event may fire before or after the snippet applies the page-specific changes specified by active variations.

pageDeactivated

Fires each time a page is deactivated.

Syntax

var pageDeactivated = function(pageDeactivated);

Parameters

Parameter and Type	Child Attribute	Description
`pageDeactivated` PageDeactivatedObject		The data relevant to the pageDeactivated event. Required.
`type` string	Child attribute of type PageDeactivatedObject	The category of an event. The value will be `lifecycle` for this event. Required.
`name` string	Child attribute of type PageDeactivatedObject	The name of the event type. This is set to `pageDeactivated`.
`data` PageEventData	Child attribute of type PageDeactivatedObject	Data associated to this event. You can use this object to determine which page has been activated.
`page` Page	Child attribute of type PageEventData	The complete page object.
`activationType` string	Child attribute of type Page	The trigger type that activates the page.
`apiName` string	Child attribute of type Page	A machine-readable name for the page. The `apiName` value can be used in the page function to indicate which event has occurred.
`category` string	Child attribute of type Page	An event category that was selected upon creation of the page. Some valid values for category are "added to cart", "saved", "shared", "searched", "purchased", "converted", "signed up", "subscribed", "other".
`deactivationEnabled` Boolean	Child attribute of type Page	Whether or not this page is automatically deactivated when its trigger fires and conditions are false.
`id` string	Child attribute of type Page	The page ID.
`staticConditions` array	Child attribute of type Page	The conditions that need to be true for the page to be activated.
`undoOnDeactivation` Boolean	Child attribute of type Page	Whether or not the changes for this page are undone when this page deactivates. Note that not all types of changes can be undone. Learn more.
`tags` array[VisualTagObject]	Child attribute of type Page	An array of the visual tags saved on a page. Read more about visual tags.
`category` string	Child attribute of type VisualTagObject	A tag category that was selected upon creation of the tag. Some valid values for category are: "category", "subcategory", "title", "price", "other".
`locator` string	Child attribute of type VisualTagObject	The logic/CSS selector indicating where a tag is located on the page.
`apiName` string	Child attribute of type VisualTagObject	A machine-readable name for the tag.
`locatorType` string	Child attribute of type VisualTagObject	A enum that indicates if the locator is custom "javascript" or a "css_selector".

Example Call

function onPageDeactivated(event) {
  console.log("The Page " + event.data.page.name + " is no longer active");
}

window["optimizely"] = window["optimizely"] || [];
window["optimizely"].push({
  type: "addListener",
  filter: {
    type: "lifecycle",
    name: "pageDeactivated"
  },
  handler: onPageDeactivated
});

Description

This event indicates when a page has been deactivated.

This event may fire before or after the snippet undoes the page-specific changes specified by active variations (if the Undo Changes setting is on for this page).

originsSynced

Fires when visitor data has been loaded from other origins.

Syntax

var originsSynced = function(originsSynced);

Parameters

Parameter and Type	Child Attribute	Description
`originsSynced` OriginsSyncedObject		The name and type of the originsSynced event. Required.
`type` string	Child attribute of type OriginsSyncedObject	The type of the event. The value will be lifecycle for this event. Required.
`name` string	Child attribute of type OriginsSyncedObject	The name of the event. The value will be originsSynced for this event.

Example Call

function onOriginsSynced() {
  console.log("Cross-origin data is now synced.");
}

window["optimizely"] = window["optimizely"] || [];
window["optimizely"].push({
  type: "addListener",
  filter: {
    type: "lifecycle",
    name: "originsSynced"
  },
  handler: onOriginsSynced
});

Description

During snippet initialization, Optimizely tries to fetch data that has been saved for the current visitor ID under other origins' localStorage. Such data may exist if the visitor has previously used the current web browser to visit other origins on which you're running Optimizely X Web snippets.

This operation is asynchronous and may complete after the initial snippet activation (unless you use the waitForOriginSync API to delay that snippet activation). The originsSynced event indicates when this operation has succeeded or failed. You may want to wait for this event before executing logic that preferably sees data from all your origins.

After the originsSynced event, syncing will continue until the page unloads, but you won't receive any more notifications.

As a security precaution, the snippet only syncs data between origins that you've listed in your account settings.

For more information, see this article on cross-origin targeting.

trackEvent

Fires whenever an X Web event has occurred.

Syntax

var trackEvent = function(trackEvent);

Parameters

Parameter and Type	Child Attribute	Description
`trackEvent` TrackEventObject		The data relevant to the trackEvent event. Required.
`type` string	Child attribute of type TrackEventObject	`analytics`
`name` string	Child attribute of type TrackEventObject	`trackEvent`
`data` TrackEventData	Child attribute of type TrackEventObject	Data associated to this event. You can use this object to determine which event was triggered.
`type` string	Child attribute of type TrackEventData	The type of the tracked event (e.g., "custom" for custom events, "pageview" for page-activated events).
`name` string	Child attribute of type TrackEventData	The name of the tracked event.
`apiName` string	Child attribute of type TrackEventData	The apiName of the tracked event. Note that for "pageview" events, this is the api_name of the page.
`category` string	Child attribute of type TrackEventData	The category of the tracked event/page.
`metrics` MetricData	Child attribute of type TrackEventData	Metrics attached to the event, if any.
`revenue` number or undefined	Child attribute of type MetricData	Revenue value associated with the event, if any.
`tags` Object	Child attribute of type TrackEventData	Map of tag name to tag value.

Example Call

function onTrackEvent(event) {
  console.log("The event " + event.data.name + " was tracked");
}

window["optimizely"] = window["optimizely"] || [];
window["optimizely"].push({
  type: "addListener",
  filter: {
    type: "analytics",
    name: "trackEvent"
  },
  handler: onTrackEvent
});

Description

The trackEvent lifecycle event is fired whenever the visitor triggers an X Web event.

You can use this API if you want to track conversions in an external analytics platform.

You can also use this to manually activate a campaign or experiment after a particular event has occurred. For more complex targeting, you can use behavioral audiences or the get('behavior') API if you have access to Optimizely Personalization.