Attributes

In addition of overriding the language/region or setting a custom user ID, you can assign attributes and tags to your users, allowing you to improve your Push targeting.

IMPORTANT
- User IDs (email address, username, etc) must be managed using our custom user ID implementation.
- Region/language data must be managed using our custom region/language implementation.
- Never use an existing tagging plan. Read our guide on custom data before tagging your app.
- Newly tracked attributes and tags are hidden by default. You will need to manually display them from the dashboard settings > "Custom data" tab.

Managing attributes

Before we get started on how to implement custom attributes, here are some rules you should know.

Naming

Attribute names are strings. They should be made of letters, numbers or underscores ([a-z0-9_]) and can't be longer than 30 characters (e.g. has_premium).

Values

Values must be any of the following types, or their native Swift equivalent:

NSString
Must not be longer than 64 characters and can be empty. For better results, you should make them upper/lowercase and trim the whitespaces.

NSNumber

• Anything bigger than a long long or a double will be rejected.
  
• Unsigned values will be rejected.
  
• Booleans are supported, but should be initialized with [NSNumber numberWithBool:<your value>] or @YES/@NO.

NSDate
Since timezones are not supported, this will typically represent UTC dates.

Using any unsupported type as a value (NSNull, NSObject, NSArray, NSDictionary for example) will NOT work. Be careful, as it may cause [editor save] to fail.

NSURL
≥ 1.18 Must not be longer than 2048 characters and must follow the format scheme://[authority][path][?query][#fragment].

Setting an attribute

The custom attribute API works using an editor. You need to get an instance of the editor, enqueue your changes and then call save.
Changes will NOT be persisted until you call this method, please make sure you call it!

There is one setAttribute/set(attribute:forKey:) method per attribute type. Use Xcode's autocompletion or see BatchUser.h for all available variants. If you're using Swift, the appropriate method will automatically be used according to the value's type.

Those methods throw an error if key/value failed validation according to the rules expressed higher up in this documentation.
The error status does not mean that the attributes have been sent to the the server, as it happens at a latter date.

Removing an attribute by settings its value to nil, like with pre 1.16 APIs is no longer supported.

// Get a new editor instance.
// You need to save this in a local variable until you call save
// Editor instances don't share changes, and calling save on an empty editor will do nothing
let editor = BatchUser.editor()

// Set an attribute. try? allows a potential error to be silently ignored
// This example is a valid key/attribute pair, and will not throw an error.
try? editor.set(attribute: 26, forKey:"age")

do {
    // Invalid attribute name, $ is a forbidden character
    try editor.set(attribute: "patricia", forKey: "fir$t_name")
} catch {
    // Handle the error here.
    // Error is of type BatchUserDataEditorError if you want to specifically
    // handle it.
}

editor.save() // Don't forget to save the changes

Please test your implementation using our debug tool before releasing your app on the store. Make sure you're unwrapping your optionals!

Legacy setAttribute

Before Batch 1.16.0, only one setAttribute variant was available. It takes any object for the value, and doesn't throw on validation errors.

Example:

// Deprecated in 1.16, use set(attribute:forKey:)
let editor = BatchUser.editor()
editor.setAttribute(26, forKey:"age")
editor.setAttribute(nil, forKey:"age") // Removes the attribute
editor.save() // Don't forget to save the changes

Removing one or multiple attributes

Use removeAttributeForKey to remove one attribute and clearAttributes to remove them all.

// Get a new editor instance.
// You need to save this in a local variable until you call save
// Editor instances don't share changes, and calling save on an empty editor will do nothing
let editor = BatchUser.editor()

editor.removeAttribute(forKey: "age") // Remove an attribute

editor.clearAttributes() // Removes all attributes

editor.save() // Don't forget to save the changes

Managing tag collections

You can attach multiple tags to different collections. Collections names can't be longer than 30 characters (e.g. favorite_categories).

Tags have some limitations:

• They are strings.
• They will automatically be lowercased
• Their size can't be greater than 64 characters and they can't be empty.

Collection names have the same limitations as attribute names.

Here are the available methods:

// Get a new editor instance.
// You need to save this in a local variable until you call save
// Editor instances don't share changes, and calling save on an empty editor will do nothing
let editor = BatchUser.editor()
editor.addTag("has_bought", inCollection: "actions") // Add a tag to the "actions" collection
editor.removeTag("has_bought", fromCollection: "actions") // Remove it

editor.clearTagCollection("actions") // Removes all tags from that collection
// editor.clearTags() // Removes all tag collections and tags

editor.save(); // Don't forget to save the changes

Reading attributes and tag collections

Since Batch 1.14, two class methods of BatchUser are available to asynchronously fetch saved attributes and tag collections.

Reading attributes

BatchUser.fetchAttributes { attributes in
    // Attributes are retrieved in the form of a dictionary
    // Values are encapsulated in an instance of BatchUserAttribute
    let attribute: BatchUserAttribute = attributes["age"]
            
    // BatchUserAttribute holds a reference to the value of the attribute
    let rawValue: Any = attribute.value // Raw value is not typed
    print(rawValue) // Prints "NSNumber(26)"
            
    // The type of the value is specified via a BatchUserAttributeType enumeration
    print(attribute.type) // Prints "BatchUserAttributeTypeLongLong"
            
    // To obtain a typed result you can use one of the four helper methods
    attribute.numberValue() // Will return "26" here
    attribute.dateValue()   // Will return nil here
    attribute.stringValue() // Will return nil here
    attribute.urlValue()    // Will return nil here
}

Reading tag collections

BatchUser.fetchTags { tagCollections in
    // Tags are also retrieved in the form of a dictionary
    // Keys are names of collections, values are sets of tags
    let tagCollection: Set<String> = tagCollections["actions"]
    print(tagCollection) // Prints "["has_bought"]"
}

Note: Since tags are limited in size and are case sensitive, reading them back might produce different results than what had been saved.