Quickstart Subscriptions

This quickstart will help you create your first subscription. We're going to subscribe to live updates for a notification thread.

DOCS E-COMMERCE SAMPLE APP

This quickstart/recipe is dependent upon the docs e-commerce sample app. If you haven't already deployed the sample app, you can do so with one click below. If you've already deployed the sample app, simply use your existing project.

Step 1: Create a Subscription

Head to the API tab of the Hasura Console and paste in this value:

subscription UserNotificationSubscription($user_id: uuid = "9bd9d300-65b7-11ed-b908-571fef22d2ba") {
  notifications(where: { user_id: { _eq: $user_id } }) {
    id
    created_at
    message
  }
}

Once hitting run, you should see the following output:

That's it?

Yep! Remember, you get subscriptions out of the box with Hasura 🔥 You'll see a few notifications in your results because they're already in the database. To test it — and see new notifications mimicking a client application — let's ping the server with curl in the next step.

Step 2: Insert a notification

To avoid the need for a client application, we'll use curl to insert a notification into the database. You can enter the curl command below into a terminal window, and replace the <YOUR_ADMIN_SECRET> and <YOUR_HASURA_PROJECT_ENDPOINT> values with your own:

curl -X POST -H "Content-Type: application/json" -H "x-hasura-admin-secret: <YOUR_ADMIN_SECRET>" -d '{"query":"mutation InsertNewNotification {\n  insert_notifications_one(object: {user_id: \"9bd9d300-65b7-11ed-b908-571fef22d2ba\", message: \"This is a live-updating subscription!\"}) {\n    id\n  }\n}"}' <YOUR_PROJECT_GRAPHQL_ENDPOINT>

After entering the above command hitting enter, you should see the following output on your Console's API tab:

Recap

What just happened? Well, you just wrote your first subscription! You can now subscribe to live updates for a notification thread. Think of the possibilities in a real-world application: you can subscribe to live updates for a chat thread, a shopping cart, or a live leaderboard.

At the start, you created a subscription using the Hasura Console's API tab. This subscription returns the id field for all notifications with a user_id equal to the provided value. This allows us to receive new data, live from the server, rather than just a single response. So, as new notifications are inserted into the database - like we did with the curl command - the subscription will return them.