Looking for reactive Apollo query controllers? See @apollo-elements/core/apollo-query-controller.
ApolloQuery inherits from ApolloElement and implements the ApolloQueryInterface.
Demo
import { ApolloQuery, html } from '@apollo-elements/lit-apollo';
import { customElement } from 'lit/decorators.js';
import { LaunchesQuery } from './Launches.query.graphql.js';
import { style } from './SpacexLaunches.css.js';
import '@apollo-elements/components/apollo-client';
@customElement('spacex-launches')
class SpacexLaunches extends ApolloQuery<typeof LaunchesQuery> {
static readonly styles = style;
variables = { limit: 3 };
query = LaunchesQuery;
render() {
const launches = this.data?.launchesPast ?? [];
return html`
<ol>${launches.map(x => html`
<li>
<article>
<span>${x.mission_name ?? ''}</span>
<img .src="${x.links?.mission_patch_small}" alt="Badge" role="presentation"/>
</article>
</li>`)}
</ol>
`;
}
}Read the query component guides for more examples and tips.
ApolloQuery
🚀 Custom element base class that connects to your Apollo cache.
See ApolloQueryInterface for more information on events
Properties
data
Data<D> | nullvariables
Variables<D, V> | nullcontroller
ApolloController<D, V>canAutoSubscribe
booleanoptions
ApolloQueryControllerOptions<D, V>| Option | Type | Description |
|---|---|---|
| fetchPolicy | WatchQueryFetchPolicy |
The fetchPolicy for the query. |
| variables | Variables<D, V> |
Variables for the query. |
| noAutoSubscribe | boolean |
If true, the element will not begin querying data until you manually call subscribe |
| shouldSubscribe | (op?: Partial<Operation<D, V>>) => boolean |
Determines whether the element should attempt to subscribe automatically\nOverride to prevent subscribing unless your conditions are met |
| onData | (data: Data<D>) => void |
Optional callback for when a query resolves. |
| onError | (error: Error) => void |
Optional callback for when an error occurs. |
Inherits from ApolloControllerOptions
networkStatus
networkStatus is useful if you want to display a different loading indicator (or no indicator at all)
depending on your network status as it provides a more detailed view into the state of a network request
on your component than loading does. networkStatus is an enum with different number values between 1 and 8.
These number values each represent a different network state.
loading: The query has never been run before and the request is now pending. A query will still have this network status even if a result was returned from the cache, but a query was dispatched anyway.setVariables: If a query’s variables change and a network request was fired then the network status will be setVariables until the result of that query comes back. React users will see this when options.variables changes on their queries.fetchMore: Indicates that fetchMore was called on this query and that the network request created is currently in flight.refetch: It means that refetch was called on a query and the refetch request is currently in flight.- Unused.
poll: Indicates that a polling query is currently in flight. So for example if you are polling a query every 10 seconds then the network status will switch to poll every 10 seconds whenever a poll request has been sent but not resolved.ready: No request is in flight for this query, and no errors happened. Everything is OK.error: No request is in flight for this query, but one or more errors were detected.
If the network status is less then 7 then it is equivalent to loading being true. In fact you could
replace all of your loading checks with networkStatus < 7 and you would not see a difference.
It is recommended that you use loading, however.
query
null | ComponentDocument<D, V>partial
booleanpartialRefetch
boolean | undefinedIf true, perform a query refetch if the query result is marked as being partial, and the returned data is reset to an empty Object by the Apollo Client QueryManager (due to a cache miss).
The default value is false for backwards-compatibility’s sake, but should be changed to true for most use-cases.
pollInterval
number | undefinedreturnPartialData
boolean | undefinednoAutoSubscribe
booleansubscribe() method to do so.notifyOnNetworkStatusChange
boolean | undefinederrorPolicy
C.ErrorPolicy | undefinederrorPolicy determines the level of events for errors in the execution result. The options 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 callnextall: errors are treated like data and will notify observables
fetchPolicy
C.WatchQueryFetchPolicy | undefinedDetermines where the client may return a result from. The options are:
cache-first(default): return result from cache, fetch from network if cached result is not available.cache-and-network: return result from cache first (if it exists), then return network result once it’s available.cache-only: return result from cache if available, fail otherwise.no-cache: return result from network, fail if network call doesn’t succeed, don’t save to cachenetwork-only: return result from network, fail if network call doesn’t succeed, save to cachestandby: only for queries that aren’t actively watched, but should be available for refetch and updateQueries.
nextFetchPolicy
this['controller']['options']['nextFetchPolicy'] | undefinedcache-and-network or network-only.When someone chooses cache-and-network or network-only as their
initial FetchPolicy, they often do not want future cache updates to
trigger unconditional network requests, which is what repeatedly
applying the cache-and-network or network-only policies would seem
to imply. Instead, when the cache reports an update after the
initial network request, it may be desirable for subsequent network
requests to be triggered only if the cache result is incomplete.
The nextFetchPolicy option provides a way to update
options.fetchPolicy after the intial network request, without
having to set options.readyToReceiveDocument
booleanclient
ApolloClient<NormalizedCacheObject> | nulldocument
ComponentDocument<D, V> | nullDocumentNodecontext
Record<string, unknown> | undefinedloading
booleanerror
Error | ApolloError | nullerrors
readonly GraphQLError[]Methods
shouldSubscribe
Determines whether the element should attempt to subscribe i.e. begin querying Override to prevent subscribing unless your conditions are metParameters
options
Partial<C.SubscriptionOptions<Variables<D, V>, Data<D>>>Returns
booleanrefetch
publicasyncExposes theObservableQuery#refetch method.Parameters
variables
Variables<D, V>Returns
Promise<C.ApolloQueryResult<Data<D>>>subscribe
publicResets the observableQuery and subscribes.Parameters
params
Partial<C.WatchQueryOptions<Variables<D, V>, Data<D>>>Returns
C.ObservableSubscriptionsubscribeToMore
publicLets you pass a GraphQL subscription and updateQuery function to subscribe to more updates for your query.
The updateQuery parameter is a function that takes the previous query data,
then a { subscriptionData: TSubscriptionResult } object,
and returns an object with updated query data based on the new results.
Parameters
options
C.SubscribeToMoreOptions<Data<D>, TSubscriptionVariables, TSubscriptionData>Returns
(() => void) | voidexecuteQuery
publicasyncExecutes a Query once and updates the with the resultParameters
params
Partial<C.QueryOptions<Variables<D, V>, Data<D>>>Returns
Promise<C.ApolloQueryResult<Data<D>>>fetchMore
publicasyncExposes the ObservableQuery#fetchMore method.
https://www.apollographql.com/docs/react/api/core/ObservableQuery/#ObservableQuery.fetchMore
The optional updateQuery parameter is a function that takes the previous query data,
then a { subscriptionData: TSubscriptionResult } object,
and returns an object with updated query data based on the new results.
The optional variables parameter is an optional new variables object.
Parameters
params
Partial<FetchMoreParams<D, V>>| Option | Type | Description |
|---|---|---|
| query | DocumentNode |
Query to fetch, defaults to this.query |
| updateQuery | Function |
Function to determine how to update the cache when the query resolves. (deprecated - use field policies instead) |
| variables | Variables<D, V> |
Query variables |
| context | Record<string, unknown> |
Context object passed through the link execution chain. |
Returns
Promise<C.ApolloQueryResult<Data<D>>>startPolling
publicParameters
ms
numberReturns
voidstopPolling
publicReturns
voidonData
Optional callback for when a query is completed.Parameters
data
Data<D>Returns
voidonError
Optional callback for when an error occurs.Parameters
error
ErrorReturns
voidEvents
apollo-element-connected
ApolloElementEventapollo-element-disconnected
ApolloElementEventExports
js ApolloQuery from apollo-query.js