Notification System

Overview

Notifications are stored in the database and hydrated with related data before being rendered. The system supports multiple notification types (comments, subscriptions, etc.) that are processed in parallel.

Key Files

• src/notifications.ts - Core notification types and hydration logic
• app/(home-pages)/notifications/NotificationList.tsx - Renders all notification types
• app/(home-pages)/notifications/Notification.tsx - Base notification component
• Individual notification components (e.g., CommentNotification.tsx, FollowNotification.tsx)

Adding a New Notification Type

1. Update Notification Data Types (src/notifications.ts)

Add your type to the NotificationData union:

export type NotificationData =
  | { type: "comment"; comment_uri: string; parent_uri?: string }
  | { type: "subscribe"; subscription_uri: string }
  | { type: "your_type"; your_field: string }; // Add here

Add to the HydratedNotification union:

export type HydratedNotification =
  | HydratedCommentNotification
  | HydratedSubscribeNotification
  | HydratedYourNotification; // Add here

2. Create Hydration Function (src/notifications.ts)

export type HydratedYourNotification = Awaited<
  ReturnType<typeof hydrateYourNotifications>
>[0];

async function hydrateYourNotifications(notifications: NotificationRow[]) {
  const yourNotifications = notifications.filter(
    (n): n is NotificationRow & { data: ExtractNotificationType<"your_type"> } =>
      (n.data as NotificationData)?.type === "your_type",
  );

  if (yourNotifications.length === 0) return [];

  // Fetch related data with joins
  const { data } = await supabaseServerClient
    .from("your_table")
    .select("*, related_table(*)")
    .in("uri", yourNotifications.map((n) => n.data.your_field));

  return yourNotifications.map((notification) => ({
    id: notification.id,
    recipient: notification.recipient,
    created_at: notification.created_at,
    type: "your_type" as const,
    your_field: notification.data.your_field,
    yourData: data?.find((d) => d.uri === notification.data.your_field)!,
  }));
}

Add to hydrateNotifications parallel array:

const [commentNotifications, subscribeNotifications, yourNotifications] = await Promise.all([
  hydrateCommentNotifications(notifications),
  hydrateSubscribeNotifications(notifications),
  hydrateYourNotifications(notifications), // Add here
]);

const allHydrated = [...commentNotifications, ...subscribeNotifications, ...yourNotifications];

3. Trigger the Notification (in your action file)

import { Notification, pingIdentityToUpdateNotification } from "src/notifications";
import { v7 } from "uuid";

// When the event occurs:
const recipient = /* determine who should receive it */;
if (recipient !== currentUser) {
  const notification: Notification = {
    id: v7(),
    recipient,
    data: {
      type: "your_type",
      your_field: "value",
    },
  };
  await supabaseServerClient.from("notifications").insert(notification);
  await pingIdentityToUpdateNotification(recipient);
}

4. Create Notification Component

Create a new component (e.g., YourNotification.tsx):

import { HydratedYourNotification } from "src/notifications";
import { Notification } from "./Notification";

export const YourNotification = (props: HydratedYourNotification) => {
  // Extract data from props.yourData

  return (
    <Notification
      timestamp={props.created_at}
      href={/* link to relevant page */}
      icon={/* icon or avatar */}
      actionText={<>Message to display</>}
      content={/* optional additional content */}
    />
  );
};

5. Update NotificationList (NotificationList.tsx)

Import and render your notification type:

import { YourNotification } from "./YourNotification";

// In the map function:
if (n.type === "your_type") {
  return <YourNotification key={n.id} {...n} />;
}

Example: Subscribe Notifications

See the implementation in:

• src/notifications.ts:88-125 - Hydration logic
• actions/publications/subscribeToPublication.ts:55-68 - Trigger
• app/(home-pages)/notifications/FollowNotification.tsx - Component
• app/(home-pages)/notifications/NotificationList.tsx:40-42 - Rendering