array attributes vs tag collections

[svenjacobs]

Hello,

we're currently implementing the Batch SDK (3.0.1) and noticed a slight confusion regarding array attributes.
The documentation states that array values should be added and removed like this

Batch.Profile.editor().apply {
   addToArray("actions", listOf("added_to_cart", "has_bought"))
   removeFromArray("actions", "has_bought")
   save()
}

but when reading an array attribute we actually have to use the tag API with Batch.User.fetchTagCollections(). The documentation states

You may also have noticed that APIs to set Tags or Tag Collections have been removed and replaced by array attributes. These methods are backward-compatible and array attributes are converted into tag collections to not break your implementation.

so this happens to not break old implementations. However for consistency it would be nice if array attributes also appear when using Batch.User.fetchAttributes(). Especially for developers that started to use Batch only recently and are not familiar with the old (and deprecated?) tag collections.

Thank you! 😃

[arnaud-roland]

Hi,

Thank you for reaching out. We understand that the distinction between the User and Profile APIs can be confusing. Let me clarify:

The Profile module, introduced in SDK 2.0, manages data at a Project scope. This is part of our Customer Engagement Platform (CEP). Data associated with a Profile is related to your overall project and can be updated from various sources, such as different SDKs or APIs. Currently, the SDKs can send data to a Profile but do not have APIs to fetch data from it.

The User module is our legacy module for managing data at an Installation scope. This is part of our Mobile Engagement Platform (MEP). Data managed via the User module is specific to a single app installation on a device and was not designed to be updated from external sources.

When you use Batch.Profile.editor() APIs, the data is sent to both platforms:

•To the CEP (Profile) for broader project-level user data.
•To the MEP (User) for backward compatibility with older systems.

The Batch.User.fetchAttributes() method, however, reads data directly from the device's local storage. It is designed to return only the data related to that specific installation (MEP data).

You're correct that Array Attributes (a CEP concept introduced in SDK 2.0) are conceptually similar to the older Tag Collections (an MEP concept). Because Batch.User.fetchAttributes() retrieves MEP-specific data, it does not include CEP-only data like Array Attributes. This separation is intentional to maintain the distinct scopes of these modules.

We are always considering future enhancements, and fetching profile-level data via the SDK is something we might explore. I will pass your feedback regarding this to our product team.

I hope this explanation helps!

You might also find this section of our SDK v2 migration guide useful.

Please let me know if you have any further questions.
Have a good day.

[svenjacobs]

Thank you Arnaud for the detailled explanation.

As far as I understand we should use the Customer Engagement Platform (CEP) to store project-level user data. But since there is no API for Batch.Profile to fetch CEP attributes, how is an app supposed to realize when an attribute has been changed from a different source? Let's say for example there is a boolean attribute that represents a switch in the app and which has an impact of how we engage with the customer through Batch?

[arnaud-roland]

Currently, you cannot directly bind your UI to custom data stored in Batch. If your UI relies on this data, we recommend managing it on your own backend server and propagating changes to Batch using Batch.Profile.editor().