Query Operations

/**
 * Execute a GraphQL query and return the result with loading/error states
 * @param query - GraphQL query document
 * @param options - Configuration options for the query
 * @returns Query result with data, loading, error states and utility functions
 */
function useQuery<TData = any, TVariables = OperationVariables>(
  query: DocumentNode,
  options?: QueryHookOptions<TData, TVariables>
): QueryResult<TData, TVariables>;

interface QueryHookOptions<TData, TVariables> extends QueryOptions<TVariables, TData> {
  /** Skip executing the query */
  skip?: boolean;
  /** Execute the query on every render */
  fetchPolicy?: FetchPolicy;
  /** Error policy for handling GraphQL errors */
  errorPolicy?: ErrorPolicy;
  /** Return partial data from cache */
  returnPartialData?: boolean;
  /** Polling interval in milliseconds */
  pollInterval?: number;
  /** Notify when network only fetchPolicy completes */
  notifyOnNetworkStatusChange?: boolean;
  /** Context passed to Apollo Link */
  context?: DefaultContext;
  /** Partial observer options */
  partialRefetch?: boolean;
  /** Client instance to use */
  client?: ApolloClient<any>;
}

interface QueryResult<TData, TVariables> {
  /** Query data */
  data?: TData;
  /** Loading state */
  loading: boolean;
  /** Error state */
  error?: ApolloError;
  /** Network status */
  networkStatus: NetworkStatus;
  /** Whether query has been called */
  called: boolean;
  /** Apollo Client instance */
  client: ApolloClient<any>;
  /** Refetch the query */
  refetch: (variables?: Partial<TVariables>) => Promise<ApolloQueryResult<TData>>;
  /** Fetch more data */
  fetchMore: <K extends keyof TVariables>(
    fetchMoreOptions: FetchMoreQueryOptions<TVariables, K> & FetchMoreOptions<TData, TVariables>
  ) => Promise<ApolloQueryResult<TData>>;
  /** Start polling */
  startPolling: (pollInterval: number) => void;
  /** Stop polling */
  stopPolling: () => void;
  /** Subscribe to more data */
  subscribeToMore: <TSubscriptionData, TSubscriptionVariables>(
    options: SubscribeToMoreOptions<TData, TSubscriptionVariables, TSubscriptionData>
  ) => () => void;
  /** Update query result */
  updateQuery: (
    mapFn: (previousQueryResult: TData, options: UpdateQueryOptions<TVariables>) => TData
  ) => void;
}

import { useQuery, gql } from "@apollo/react-hooks";

const GET_USERS = gql`
  query GetUsers($limit: Int) {
    users(limit: $limit) {
      id
      name
      email
    }
  }
`;

function UsersList() {
  const { loading, error, data, refetch } = useQuery(GET_USERS, {
    variables: { limit: 10 },
    fetchPolicy: "cache-first",
    pollInterval: 5000, // Poll every 5 seconds
  });

  if (loading) return <div>Loading...</div>;
  if (error) return <div>Error: {error.message}</div>;

  return (
    <div>
      <button onClick={() => refetch()}>Refresh</button>
      <ul>
        {data?.users.map(user => (
          <li key={user.id}>{user.name}</li>
        ))}
      </ul>
    </div>
  );
}

/**
 * Create a query function that can be called on-demand
 * @param query - GraphQL query document
 * @param options - Configuration options for the lazy query
 * @returns Tuple with execute function and query result
 */
function useLazyQuery<TData = any, TVariables = OperationVariables>(
  query: DocumentNode,
  options?: LazyQueryHookOptions<TData, TVariables>
): LazyQueryResult<TData, TVariables>;

type LazyQueryResult<TData, TVariables> = [
  LazyQueryExecuteFunction<TData, TVariables>,
  QueryResult<TData, TVariables>
];

type LazyQueryExecuteFunction<TData, TVariables> = (
  options?: QueryLazyOptions<TVariables>
) => Promise<QueryResult<TData, TVariables>>;

interface LazyQueryHookOptions<TData, TVariables> 
  extends Omit<QueryHookOptions<TData, TVariables>, 'skip'> {}

interface QueryLazyOptions<TVariables> {
  /** Variables to pass to the query */
  variables?: TVariables;
  /** Context for the query */
  context?: DefaultContext;
}

import { useLazyQuery, gql } from "@apollo/react-hooks";

const SEARCH_USERS = gql`
  query SearchUsers($query: String!) {
    searchUsers(query: $query) {
      id
      name
      email
    }
  }
`;

function UserSearch() {
  const [searchUsers, { loading, error, data }] = useLazyQuery(SEARCH_USERS);

  const handleSearch = (searchTerm: string) => {
    searchUsers({ variables: { query: searchTerm } });
  };

  return (
    <div>
      <input 
        type="text" 
        onChange={(e) => handleSearch(e.target.value)}
        placeholder="Search users..."
      />
      {loading && <div>Searching...</div>}
      {error && <div>Error: {error.message}</div>}
      {data && (
        <ul>
          {data.searchUsers.map(user => (
            <li key={user.id}>{user.name}</li>
          ))}
        </ul>
      )}
    </div>
  );
}

type FetchPolicy = 
  | 'cache-first'
  | 'cache-only'
  | 'cache-and-network'
  | 'network-only'
  | 'no-cache'
  | 'standby';

type ErrorPolicy = 'none' | 'ignore' | 'all';

enum NetworkStatus {
  loading = 1,
  setVariables = 2,
  fetchMore = 3,
  refetch = 4,
  poll = 6,
  ready = 7,
  error = 8,
}

interface FetchMoreQueryOptions<TVariables, K extends keyof TVariables> {
  variables?: Pick<TVariables, K>;
}

interface FetchMoreOptions<TData, TVariables> {
  updateQuery?: (
    previousQueryResult: TData,
    options: {
      fetchMoreResult?: TData;
      variables?: TVariables;
    }
  ) => TData;
}