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Preferences

Overview

Preferences overview

Learn how to implement notification preferences in Knock.

Preferences enable your users to opt-out of the notifications you send using Knock.

How preferences work

A user has a PreferenceSet. A PreferenceSet is a JSON object that tells Knock which channels, categories, and/or workflows a user has opted out of receiving.

When Knock runs a workflow for a user, we evaluate their PreferenceSet. A message will not send if the user has opted out of receiving it.

A preference set is built using three keys: categories, channel_types, workflows. These keys resolve to boolean values to determine if a user has opted out of receiving a notification.

A recipient's default preference set also has a commercial_unsubscribe key which determines if the recipient should receive notifications sent by commercial workflows or broadcasts. Read more about commercial unsubscribe here.

A few examples:

You can combine these keys to create preference grids like the one in the image below:

The PreferenceSet above models this preference grid in your application:

Build your preference center

Before you start setting preferences for your users, you need to build a preference center in your application. A preference center is a place where users can manage their notification preferences.

There are four steps to building a preference center with Knock:

Create a default PreferenceSet

A default preference set is the PreferenceSet users default to using when they first sign up for your product. Any users who don't have a preference set will default to using the default preference set. You can create a default preference set in the Knock dashboard under Developers > Preferences.

Creating a default preference set in Knock dashboard

The default preference set is environment-specific for testing purposes. You can copy the default preference set from one environment to another to keep your environments in sync.

Get a user's preferences

Once you have your default PreferenceSet created, you will use the getPreferences method to retrieve a user's preferences for rendering in your application. If no preferences are set, this method will return the default preference set you created in the step above.

Render your preference center

Once you have loaded a user's preference, you'll need to render an interface in your application so they can update their notification preferences. Typically you encapsulate all of the getting and setting of preferences in a single component.

You can see an example of this below, but our quickstart guide on building preferences UI provides an in-depth walkthrough of how to build a functional PreferenceCenter component.

Set a user's preferences

When a user makes changes to their preferences in your application, you will use the setPreferences method to save those changes back to Knock.

You can learn more about rendering preferences to users in your application in the Building In-app UI section of our documentation:

Quickstart: Preference UIs in React

React

Javascript SDK preference reference

JavaScript

Merging preferences

When a default PreferenceSet exists for an environment or tenant, Knock will merge all applicable preferences for a recipient when evaluating whether or not to send a notification. Any preferences set at the recipient-level will take precedence in the merge.

Preference evaluation rules

When a workflow is triggered, Knock will evaluate the preferences for each recipient of the workflow and send notifications for each channel step in the workflow based on that evaluation. There are some important rules and caveats to consider:

If you do not set a preference for a given channel, workflow, or workflow category, Knock defaults them to true.
When a recipient clicks an unsubscribe link, their default preference set will be updated, marking commercial_unsubscribe as true. They will be opted-out of commercial messages, and they will continue to receive transactional messages based on their other preferences. Read more about commercial unsubscribe here.

Knock only sends a notification if all preference combinations that exist on the recipient evaluate to true.

A workflow can belong to multiple categories. Only one of those category preferences needs to evaluate to false for the notification not to send.
If a workflow's category is set to false, the notification will not send even if a channel_type on the workflow is explicitly set to true.

Our Preferences API provides endpoints for retrieving all of the preferences that have been set on a recipient.

You can also use the workflow debugger in your dashboard to view the preferences that were evaluated for the recipient on a given workflow run.

An image of a workflow run's evaluated preferences

Bulk set user preferences

You can update the preferences of up to 1000 users in a single batch by using the users.bulkSetPreferences method. This executes an asynchronous job which will overwrite any existing preferences for the users provided. You can track the progress of the BulkOperation returned via the bulk operation API.

Advanced concepts

Per-tenant preferences. In multi-tenant B2B applications, an advanced use case is customer admins who want to set the tenant-level default PreferenceSet for new users within their tenant.
Object preferences. In the guide above, we referred to user preferences. You can also set preferences for objects.
Preference conditions. You can build advanced conditions and store them on Knock’s preference model to power use cases such as per-resource muting (example: mute notifications about this task) or threshold alerts (example: only notify me if my account balance is below $5).
Workflow overrides. If you need to override a recipient's notification preferences to send notifications like a password reset email, you can override the preferences model. To do this, go to your workflow, click "Manage workflow," and enable "Override recipient preferences." You will need to commit this change for it to take effect. When enabled, the workflow will send to all of its channels, regardless of the recipient's preferences.
Commercial unsubscribe. You can configure 1-click unsubscribe links to help users opt-out of commercial or promotional notifications and comply with CAN-SPAM requirements.