Custom User Data - Java SDK
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You can read arbitrary data about your application users, known as custom user data, directly within your java application. For example, you might store a user's preferred language, date of birth, or local timezone. To learn more about custom user data, see Enable Custom User Data.
To use custom user data, you must first Enable Custom User Data.
Read a User's Custom Data
You can read the custom user data of a currently logged in user
through that user's User object. You cannot edit custom user data
through a User object. To edit custom user data, see
Update Custom User Data.
To access the data, call the
User.customData()
method on the User object of a logged in user:
MongoDB Realm does not dynamically update the value of User.customData() immediately when underlying data changes. Instead, MongoDB Realm fetches the most recent version of custom user data whenever a user refreshes their access token, which occurs during most SDK operations that contact the MongoDB Realm back end. Realm refreshes access tokens every 30 minutes, so custom user data can be stale for no more than 30 minutes.
If you require the most recent version of custom user data, use the User.refreshCustomData() method to request the latest version of a user's custom data.
Create a User's Custom Data Document
To create, update, or delete custom user data, you will need the following information from your custom user data configuration:
- the custom user data cluster
- the custom user data database
- the custom user data collection in which custom user data documents are stored
- the user ID field used to map custom user data documents to users (via user ID)
You can find this information in the Realm UI on the App Users page under the Custom User Data tab.
To create custom user data for a user, create a MongoDB document in the
custom user data collection. The user ID field of the document should
contain the the user's user ID. The following example uses
MongoDB Data Access to insert a
document containing the user ID of the currently logged in user and a
favoriteColor value into the custom user data collection:
You can add any number of arbitrary fields and values to the custom user
data document when you create it. The user ID field is the only
requirement for the document to become available on the User object
as custom user data.
Update a User's Custom Data
You can update custom user data using MongoDB Data Access, Realm Sync, MongoDB Compass, or the MongoDB Atlas Data Explorer.
To update a user's custom user data with MongoDB Data Access, edit the
MongoDB document whose user ID field contains the user ID of the user.
The following example uses MongoDB Data Access to update the favoriteColor field of
the the document containing the user ID of the currently logged in user
in the custom user data collection:
To determine a user's ID, access the User.id property or find the user in the Realm UI
on the App Users page under the Users tab.