Absinthe.Subscription (absinthe v1.5.4) View Source

Real time updates via GraphQL

For a how to guide on getting started with Absinthe.Subscriptions in your phoenix project see the Absinthe.Phoenix package.

Define in your schema via Absinthe.Schema.subscription/2

Basic Usage

Performance Characteristics

There are a couple of limitations to the beta release of subscriptions that are worth keeping in mind if you want to use this in production:

By design, all subscription docs triggered by a mutation are run inside the mutation process as a form of back pressure.

At the moment however database batching does not happen across the set of subscription docs. Thus if you have a lot of subscription docs and they each do a lot of extra DB lookups you're going to delay incoming mutation responses by however long it takes to do all that work.

Before the final version of 1.4.0 we want

Batching across subscriptions
More user control over back pressure / async balance.

Link to this section Summary

Types

subscription_field_spec()

Functions

child_spec(pubsub)

publish(pubsub, mutation_result, info)

Publish a mutation

start_link(pubsub)

Add Absinthe.Subscription to your process tree.

Link to this section Types

subscription_field_spec()

Specs

subscription_field_spec() :: {atom(), term() | (term() -> term())}

Link to this section Functions

child_spec(pubsub)

publish(pubsub, mutation_result, info)

Specs

publish(
  Absinthe.Subscription.Pubsub.t(),
  term(),
  Absinthe.Resolution.t() | [subscription_field_spec()]
) :: :ok

Publish a mutation

This function is generally used when trying to publish to one or more subscription fields "out of band" from any particular mutation.

Examples

Note: As with all subscription examples if you're using Absinthe.Phoenix pubsub will be MyAppWeb.Endpoint.

Absinthe.Subscription.publish(pubsub, user, [new_users: user.account_id])

# publish to two subscription fields
Absinthe.Subscription.publish(pubsub, user, [
  new_users: user.account_id,
  other_user_subscription_field: user.id,
])

start_link(pubsub)

Add Absinthe.Subscription to your process tree.