Interfaces: ApolloSubscription

Subscription components update in real time in reaction to events on your GraphQL server. They are ideal for uses like chat rooms or stock tickers.

Subscription components inherit the ApolloElementInterface.

Common interface for subscription elements

See ApolloElementInterface for more information on events

Properties

static

documentType

(read-only) inherited from ApolloElementElement

'document'|'query'|'mutation'|'subscription'

public

subscription

ComponentDocument<D> | null

A GraphQL document containing a single subscription.

public

skip

boolean

If true, the query will be skipped entirely

public

shouldResubscribe

boolean | ((options: SubscriptionDataOptions<Data<D>, Variables<D, V>>) => boolean)

Determines if your subscription should be unsubscribed and subscribed again.

public

pollInterval

number | undefined

The time interval (in milliseconds) on which this subscription should be refetched from the server.

public

notifyOnNetworkStatusChange

boolean | undefined

Whether or not updates to the network status should trigger next on the observer of this subscription.

public

noAutoSubscribe

no-auto-subscribe

boolean

If true, the element will not begin querying data until you manually call subscribe

public

canAutoSubscribe

(read-only)

boolean

Flags an element that's ready and able to auto subscribe

public

client

inherited from ApolloElementElement

ApolloClient<NormalizedCacheObject> | null

The Apollo Client instance.

public

context

inherited from ApolloElementElement

Record<string, unknown> | undefined

Context passed to the link execution chain.

public

controller

inherited from ApolloElementElement

ApolloController<D, V>

public

data

inherited from ApolloElementElement

Data<D> | null

Latest Data.

Latest subscription data.

public

document

inherited from ApolloElementElement

ComponentDocument<D> | null

Operation document.

GraphQL operation document i.e. query, subscription, or mutation. Must be a parsed GraphQL DocumentNode, so use graphql-tag.

public

error

inherited from ApolloElementElement

Error | ApolloError | null

Latest error

public

errorPolicy

inherited from ApolloElementElement error-policy

ErrorPolicy | undefined

Error Policy for the operation.

Much like fetchPolicy, errorPolicy allows you to control how GraphQL errors from the server are sent to your UI code. By default, the error policy treats any GraphQL Errors as network errors and ends the request chain. It doesn't save any data in the cache, and renders your UI with the error property set to an ApolloError. By changing this policy per request, you can adjust how GraphQL Errors are managed by your UI. The possible options for errorPolicy are:

none (default): any errors from the request are treated like runtime errors and the observable is stopped (XXX this is default to lower breaking changes going from AC 1.0 => 2.0)
ignore: errors from the request do not stop the observable, but also don't call next
all: errors are treated like data and will notify observables

public

errors

inherited from ApolloElementElement

readonly GraphQLError[]

Latest errors

public

fetchPolicy

inherited from ApolloElementElement fetch-policy

string | undefined

Specifies the FetchPolicy to be used for this subscription.

public

loading

inherited from ApolloElementElement

boolean

Whether a request is in flight.

public

readyToReceiveDocument

inherited from ApolloElementElement

boolean

True when the element is connected and ready to receive its GraphQL document

public

variables

inherited from ApolloElementElement

Variables<D, V> | null

Subscription variables.

An object map from variable name to variable value, where the variables are used within the GraphQL subscription.

Setting variables will initiate the subscription, unless noAutoSubscribe is also set.

Methods

public

Resets the subscription and subscribes.

params

Partial<SubscriptionDataOptions<D, V>>

Option	Type	Description
client	`ApolloClient`	Apollo Client to use for the subscription.
context	`Record<string, unknown>`	Context object passed through the link execution chain.
errorPolicy	`ErrorPolicy`	Error policy to use for the subscription. See errorPolicy
fetchPolicy	`FetchPolicy`	See fetchPolicy
shouldResubscribe	`boolean`	Boolean, or a predicate function of `SubscriptionDataOptions` that determines if your subscription should be unsubscribed and subscribed again
skip	`boolean`	If skip is true, the subscription will be skipped entirely.
subscription	`DocumentNode`	GraphQL document with a single subscription.
variables	`Variables<D, V>`	An object containing all of the variables your subscription needs to execute.

void

public

shouldSubscribe

Determines whether the element should attempt to subscribe automatically Override to prevent subscribing unless your conditions are met

Parameters

options

Partial<SubscriptionOptions<Variables<D, V>, Data<D>>>

Property	Type	Description
query	`DocumentNode`	See query
variables	`Variables<D, V>`	See variables
fetchPolicy	`FetchPolicy`	See fetchPolicy
errorPolicy	`ErrorPolicy`	See errorPolicy
context	`Record<string, unknown>`	Context object passed through the link execution chain.

Returns

boolean

public

onSubscriptionData

Callback for when data is updated

Parameters

_result

OnSubscriptionDataParams<Data<D>>

Returns

void

public

onSubscriptionComplete

Callback for when subscription completes.

Returns

void

public

onError

Callback for when error is updated

Parameters

error

ApolloError

Returns

void

public

cancel

Cancels and clears the subscription

Returns

void

Events

Name	Type	Description
apollo-subscription-result	`ApolloSubscriptionResultEvent`	The subscription updated
apollo-error	`CustomEvent<ApolloError>`	The subscription produced an error
apollo-element-connected	`ApolloElementEvent`	The element connected to the DOM
apollo-element-disconnected	`ApolloElementEvent`	The element disconnected from the DOM

Private API

Private Methods

protected

documentChanged

inherited from ApolloElementElement

Lifecycle callback that reacts to changes in the GraphQL document

Parameters

document

ComponentDocument<D> | null

Returns

void

protected

variablesChanged

inherited from ApolloElementElement

Lifecycle callback that reacts to changes in the operation variables

Parameters

variables

Variables<D, V> | null

Returns

void

Exports

import {
  CustomElement,
  ControllerHost,
  ApolloElementElement,
  ApolloMutationElement,
  ApolloQueryElement,
  ApolloSubscriptionElement
} from '@apollo-elements/core/types';