跳过参数在来自@apollo/react-hooks 的 useQuery 钩子中被忽略

Question

问题：

你好，所以我在我的 ReactJS 应用程序上使用 apollo-client 已经有一段时间了。我刚刚注意到，有时当我使用useQuery钩子时，执行完全忽略skip参数，并继续onCompleted（尽管没有任何数据）。有趣的是，它也没有向我的端点发出 API 请求。但是，如果我只是设置skip为 false，那么一切正常（如预期）。

此外，每次我使用useQuerywith时都不会发生这种情况skip，它似乎适用于某些而不是其他。

为什么 apollo 忽略skip参数并onCompleted立即使用空数据执行？有没有修复（除了useLazyQuery）？

代码示例：

const userQuery = useQuery(GET_USER, {
    variables: {
      value: userId,
    },
    skip: true,
    onCompleted: props => {
      console.log(`props => `, props)
      const {
        user: { type, role, firstName, lastName, permissions },
      } = props;

      setValue('firstName', firstName);
      setValue('lastName', lastName);
      setValue(
        'type',
        userTypes.find(({ value }) => value === type),
      );
      setValue(
        'role',
        userRoles.find(({ value }) => value === role),
      );
    },
  });

补充说明：

• 从 onCompleted 函数记录道具的输出是props => undefined。

• 我添加skip: true只是为了证明它实际上不起作用。

• 如果我记录userQuery自己，那么在第一个日志上，立即userQuery.called等于 true（但就像我之前所说的，实际上没有执行 API 调用）

依赖关系

"@apollo/react-hooks": "^3.1.5",
"apollo-cache-inmemory": "^1.6.3",
"apollo-client": "^2.6.10",
"apollo-datasource-rest": "^0.6.6",
"apollo-link": "^1.2.13",
"apollo-link-context": "^1.0.19",
"apollo-link-error": "^1.1.12",
"apollo-link-rest": "^0.7.3",
"apollo-link-retry": "^2.2.15",
"apollo-link-token-refresh": "^0.2.7",
"apollo-upload-client": "^11.0.0",
"react": "16.10.2",
"react-apollo": "^3.1.3",

笔记：

useLazyQuery似乎工作正常，因此作为一种解决方法，您可以同时使用它useEffect来实现类似的结果。

Answer 1

Apollo 客户端有问题。跳过中的错误是一个烦人的错误。您可以放弃 GraphQL，或解决它们。我建议放弃它，但如果你不能，这里有一个解决方法。该模块的工作方式与 useQuery 类似，并且可以跳过工作。它对于完整规范来说并不完整，但应该可以帮助您入门。

import { useEffect, useState } from 'react';
import { QueryHookOptions, useApolloClient } from '@apollo/react-hooks';
import { ApolloQueryResult, NetworkStatus, QueryOptions, ApolloError } from 'apollo-client';

interface DocumentNode {
    loc: {
        source: {
            body: string;
        };
    };
}

interface QueryResult<T> extends ApolloQueryResult<T> {
    error?: Error | ApolloError;
    refetch?: () => void;
}

/**
 * Method: useQuery
 * Description: enable skip on useQuery. There is a bug that currently ignores it. The bug is confirmed in the 3.2 release as well.
 * Note: https://github.com/apollographql/react-apollo/issues/3492
 */
export function useQuery<T>(
    query: DocumentNode,
    options?: QueryHookOptions
): QueryResult<T | null> {
    // Note: using useApolloClient because useLazyQuery fires on initialization. If we are skipping, we don't even want the first fire.
    const apolloClient = useApolloClient();
    const [result, setQueryResult] = useState<QueryResult<T | null>>({
    // Note: initial state
        data: null,
        loading: false,
        stale: false,
        networkStatus: NetworkStatus.ready
    });

    const setResult = (res: QueryResult<T | null>) => {
    // Note: GraphQL and Apollo can't decide if they want to return errors, or error in the type contract. I want to be sure the contract is stable. If there are errors, there will be error.
    if (res.errors?.length && !res.error) {
        [res.error] = res.errors;
    }
    // Note: Functions should always exist even if the query is not complete.
    if (!res.refetch) {
        res.refetch = () => {
            if (!result.loading) {
                execQuery();
            }
        };
      }
      setQueryResult(res);
  };

  const execQuery = async () => {
      // Note: loading state. Not spreading "...result" to allow errors to be reset.
      setResult({
          data: options?.fetchPolicy === 'no-cache' ? null : result.data,
          loading: true,
          networkStatus: NetworkStatus.loading,
          stale: true
      });
      try {
          const queryOptions = ({
              ...options,
              query
          } as unknown) as QueryOptions;
          
          await apolloClient
              .query(queryOptions)
              .then(result => {
                  setResult(result);
                  if(options?.onCompleted) options.onCompleted(result.data);
              })
              .catch(err => {
                  setResult(err);
                  if(options?.onError) options.onError(err);
              });
          
      } catch (err) {
          // Note: fail state
          setResult({
              ...result,
              loading: false,
              errors: [err],
              error: err,
              stale: true,
              networkStatus: NetworkStatus.error
          });
      }
  };

  useEffect(() => {
      // Note: Skip Functionality
      if (!result.loading && options?.skip !== true) {
           execQuery();
      }
  // Note only listen too explicit variables. If you listen to whole objects they are always different and will cause endless loops.
  }, [options?.skip, query.loc.source.body]);

  return result;
}