Subjects

The Subject object lets you send any additional information about your application’s environment, current user etc to Snowplow.

To create a new subject:

$subject = new Subject();
Code language: PHP (php)

By default the subject has one piece information in it already, the platform [“p” => “srv”].

The Subject class contains a variety of ‘set’ methods to attach extra data to your event.

• setPlatform
• setUserId
• setScreenRes
• setViewport
• setColorDepth
• setTimezone
• setLanguage
• setIpAddress
• setUseragent
• setNetworkUserId
• setSessionId
• setSessionIndex

These set methods can be called either directly onto a subject object:

$subject = new Subject();
$subject->setPlatform("tv");
Code language: PHP (php)

Or they can be called through the tracker object:

$tracker->returnSubject()->setPlatform("tv");
Code language: PHP (php)

setPlatform

The default platform is “srv”. You can change the platform of the subject by calling:

$subject->setPlatform($platform);
Code language: PHP (php)

For example:

$subject->setPlatform("tv") # Running on a Connected TV
Code language: PHP (php)

For a full list of supported platforms, please see the Snowplow Tracker Protocol.

setUserId

You can set the user ID to any string:

$subject->setUserId($id);
Code language: PHP (php)

Example:

$subject->setUserId("jbeem");
Code language: PHP (php)

setScreenResolution

If your PHP code has access to the device’s screen resolution, then you can pass this in to Snowplow too:

$subject->setScreenResolution($width, $height);
Code language: PHP (php)

Both numbers should be positive integers; note the order is width followed by height. Example:

$subject->setScreenResolution(1366, 768);
Code language: PHP (php)

setViewport

If your PHP code has access to the viewport dimensions, then you can pass this in to Snowplow too:

$subject->setViewport($width, $height);
Code language: PHP (php)

Both numbers should be positive integers; note the order is width followed by height. Example:

$subject->setViewport(300, 200);
Code language: PHP (php)

setColorDepth

If your PHP code has access to the bit depth of the device’s color palette for displaying images, then you can pass this in to Snowplow too:

$subject->setColorDepth($depth);
Code language: PHP (php)

The number should be a positive integer, in bits per pixel. Example:

$subject->setColorDepth(32);
Code language: PHP (php)

setTimezone

This method lets you pass a user’s timezone in to Snowplow:

$subject->setTimezone($timezone);
Code language: PHP (php)

The timezone should be a string:

$subject->setTimezone("Europe/London");
Code language: PHP (php)

setLanguage

This method lets you pass a user’s language in to Snowplow:

$subject->setLanguage($language);
Code language: PHP (php)

The language should be a string:

$subject->setLanguage('en');
Code language: PHP (php)

setIpAddress

This method lets you pass a user’s IP Address in to Snowplow:

$subject->setIpAddress($ip);
Code language: PHP (php)

The IP Address should be a string:

$subject->setIpAddress('127.0.0.1');
Code language: PHP (php)

setUseragent

This method lets you pass a useragent in to Snowplow:

$subject->setUseragent($useragent);
Code language: PHP (php)

The useragent should be a string:

$subject->setUseragent('Agent Smith');
Code language: PHP (php)

setNetworkUserId

This method lets you pass a Network User ID in to Snowplow:

$subject->setNetworkUserId($networkUserId);
Code language: PHP (php)

The network user id should be a string:

$subject->setNetworkUserId("network-id");
Code language: PHP (php)

setDomainUserId

This method lets you pass a Domain User ID in to Snowplow:

$subject->setDomainUserId($domainUserId);
Code language: PHP (php)

The domain user id should be a string:

$subject->setDomainUserId("domain-id");
Code language: PHP (php)

setSessionId

This method lets you pass a session ID in to Snowplow:

$subject->setSessionId($sessionId);
Code language: PHP (php)

The session ID should be a string:

$subject->setSessionId("759e1c9a-6b74-403c-8b6f-18eb9f0c2f02");
Code language: PHP (php)

setSessionIndex

This method lets you pass a session index in to Snowplow:

$subject->setSessionIndex($sessionIndex);
Code language: PHP (php)

The session index should be a number:

$subject->setSessionIndex(1);
Code language: PHP (php)