@apollo/client 4.0.0-alpha.14

v4.0.0-alpha.14

on Node.js Yarn

Major Changes

• #12614 d2851e2 Thanks @jerelmiller! - The getCacheKey function is no longer available from operation.getContext() in the link chain. Use operation.client.cache.identify(obj) in the link chain instead.

• #12556 c3fceda Thanks @phryneas! - ObservableQuery will now keep previous data around when emitting a loading state, unless query or variables changed.
  Note that @exports variables are not taken into account for this, so data will stay around even if they change.

• #12556 c3fceda Thanks @phryneas! - Removed getLastResult, getLastError and resetLastResults from ObservableQuery

• #12614 d2851e2 Thanks @jerelmiller! - Removes the resolvers option from ApolloClient. Local resolvers have instead been moved to the new LocalState instance which is assigned to the localState option in ApolloClient. To migrate, move the resolvers values into a LocalState instance and assign that instance to localState.

  new ApolloClient({
  - resolvers: { /* ... */ }
  + localState: new LocalState({
  +   resolvers: { /* ... */ }
  + }),
  });

• #12614 d2851e2 Thanks @jerelmiller! - Remove local resolvers APIs from ApolloClient in favor of localState. Methods removed are:

  • addResolvers
  • getResolvers
  • setResolvers
  • setLocalStateFragmentMatcher

• #12614 d2851e2 Thanks @jerelmiller! - Third-party caches must now implement the fragmentMatches API. Additionally fragmentMatches must be able to handle both InlineFragmentNode and FragmentDefinitionNode nodes.

  class MyCache extends ApolloCache {
    // This is now required
    public fragmentMatches(
      fragment: InlineFragmentNode | FragmentDefinitionNode,
      typename: string
    ): boolean {
      return; // ... logic to determine if typename matches fragment
    }
  }

• #12556 c3fceda Thanks @phryneas! - Reworked the logic for then a loading state is triggered. If the link chain responds synchronously, a loading state will be omitted, otherwise it will be triggered.
  If local resolvers are used, the time window for "sync vs async" starts as soon as @exports variables are resolved.

• #12556 c3fceda Thanks @phryneas! - Dropped the saveAsLastResult argument from ObservableQuery.getCurrentResult

• #12614 d2851e2 Thanks @jerelmiller! - The resolver function's context argument (the 3rd argument) has changed to provide additional information without the possibility of name clashes. Previously the context argument would spread request context and override the client and cache properties to give access to both inside of a resolver. The context argument takes now takes the following shape:

  {
    // the request context. By default `TContextValue` is of type `DefaultContext`,
    // but can be changed if a `context` function is provided.
    requestContext: TContextValue,
    // The client instance making the request
    client: ApolloClient,
    // Whether the resolver is run as a result of gathering exported variables
    // or resolving the value as part of the result
    phase: "exports" | "resolve"
  }

  To migrate, pull any request context from requestContext and the cache from the client property:

  new LocalState({
    resolvers: {
      Query: {
  -     myResolver: (parent, args, { someValue, cache }) => {
  +     myResolver: (parent, args, { requestContext, client }) => {
  +       const someValue = requestContext.someValue;
  +       const cache = client.cache;
        }
      }
    }
  });

• #12614 d2851e2 Thanks @jerelmiller! - Apollo Client no longer ships with support for @client fields out-of-the-box and now must be opt-in. To opt in to use @client fields, pass an instantiated LocalState instance to the localState option. If a query contains @client and local state hasn't been configured, an error will be thrown.

  import { LocalState } from "@apollo/client/local-state";
  
  new ApolloClient({
    localState: new LocalState(),
  });

• #12614 d2851e2 Thanks @jerelmiller! - Remove the fragmentMatcher option from ApolloClient. Custom fragment matchers used with local state are no longer supported. Fragment matching is now performed by the configured cache via the cache.fragmentMatches API.

• #12556 c3fceda Thanks @phryneas! - A call to ObservableQuery.setVariables with different variables or a ObservableQuery.refetch call will always now guarantee that a value will be emitted from the observable, even if it is deep equal to the previous value.

Minor Changes

• #12614 d2851e2 Thanks @jerelmiller! - Revamp local resolvers and fix several issues from the existing resolvers option.

  • Throwing errors in a resolver will set the field value as null and add an error to the response's errors array.
  • Remote results are dealiased before they are passed as the parent object to a resolver so that you can access fields by their field name.
  • You can now specify a context function that you can use to customize the requestContext given to resolvers.
  • The LocalState class accepts a Resolvers generic that provides autocompletion and type checking against your resolver types to ensure your resolvers are type-safe.
  • data: null is now handled correctly and does not call your local resolvers when the server does not provide a result.
  • Additional warnings have been added to provide hints when resolvers behave unexpectedly.

  import { LocalState } from "@apollo/client/local-state";
  
  import { Resolvers } from "./path/to/local-resolvers-types.ts";
  
  // LocalState now accepts a `Resolvers` generic.
  const localState = new LocalState<Resolvers>({
    // The return value of this funciton
    context: (options) => ({
      // ...
    }),
    resolvers: {
      // ...
    },
  });
  
  // You may also pass a `ContextValue` generic used to ensure the `context`
  // function returns the correct type. This type is inferred from your resolvers
  // if not provided.
  new LocalState<Resolvers, ContextValue>({
    // ...
  });