@apollo/client

Ensure cache.readQuery and cache.readFragment always return TData | null, instead of throwing MissingFieldError exceptions when missing fields are encountered.

HttpLink will now automatically strip any unused variables before sending queries to the GraphQL server, since those queries are very likely to fail validation, according to the All Variables Used rule in the GraphQL specification. If you depend on the preservation of unused variables, you can restore the previous behavior by passing includeUnusedVariables: true to the HttpLink constructor (which is typically passed as options.link to the ApolloClient constructor).

Ensure MockLink (used by MockedProvider) returns mock configuration errors (e.g. No more mocked responses for the query ...) through the Link's Observable, instead of throwing them. These errors are now available through the error property of a result.

Unsubscribing the last observer from an ObservableQuery will once again unsubscribe from the underlying network Observable in all cases, as in Apollo Client 2.x, allowing network requests to be cancelled by unsubscribing.

The independent QueryBaseOptions and ModifiableWatchQueryOptions interface supertypes have been eliminated, and their fields are now defined by QueryOptions.

Internally, Apollo Client now avoids nested imports from the graphql package, importing everything from the top-level package instead. For example,