Question

由于网络错误导致重试时，我正在React应用程序中呈现通知。如果/建立连接（重试成功），我希望清除所有此类通知

我使用apollo-link-retry并使用自定义attempts回调在重试循环开始和超时时对缓存进行突变。可以，但是成功重试时通知会保留在屏幕上，因为成功重试后不会调用回调，所以我无法从缓存中清除通知。

我尝试使用具有类似问题的apollo-link-error实现类似的逻辑。仅当发生错误并且成功重试不是错误时，才会调用链接。

这是我对apollo-link-retry的配置，“几乎”有效：

const retryLink = new RetryLink({
  attempts: (count) => {
    let notifyType
    let shouldRetry = true
    if (count === 1) {
      notifyType = 'CONNECTION_RETRY'
      shouldRetry = true
    } else if (count <= 30) {
      shouldRetry = true
    } else {
      notifyType = 'CONNECTION_TIMEOUT'
      shouldRetry = false
    }
    if (notifyType) {
      client.mutate({
        mutation: gql`
          mutation m($notification: Notification!) {
            raiseNotification(notification: $notification) @client
          }
        `,
        variables: {
          notification: { type: notifyType }
        }
      })
    }
    return shouldRetry
  }
})

也许我需要实现一个自定义链接才能完成此任务？我希望找到一种方法来利用apollo-link-retry的不错的重试逻辑，并随着逻辑的进行进一步发出一些要缓存的状态。

Answer 1

我通过做两件事实现了预期的行为：

通过attempts函数在链接上下文中保持重试计数：

new RetryLink({
  delay: {
    initial: INITIAL_RETRY_DELAY,
    max: MAX_RETRY_DELAY,
    jitter: true
  },
  attempts: (count, operation, error) => {
    if (!error.message || error.message !== 'Failed to fetch') {
      // If error is not related to connection, do not retry
      return false
    }
    operation.setContext(context => ({ ...context, retryCount: count }))
    return (count <= MAX_RETRY_COUNT)
  }
})

实施自定义链接，该链接将错误和已完成的事件订阅到链接链的更下方，并使用新的上下文字段来决定是否引发通知：

new ApolloLink((operation, forward) => {
  const context = operation.getContext()
  return new Observable(observer => {
    let subscription, hasApplicationError
    try {
      subscription = forward(operation).subscribe({
        next: result => {
          if (result.errors) {
            // Encountered application error (not network related)
            hasApplicationError = true
            notifications.raiseNotification(apolloClient, 'UNEXPECTED_ERROR')
          }
          observer.next(result)
        },
        error: networkError => {
          // Encountered network error
          if (context.retryCount === 1) {
            // Started retrying
            notifications.raiseNotification(apolloClient, 'CONNECTION_RETRY')
          }
          if (context.retryCount === MAX_RETRY_COUNT) {
            // Timed out after retrying
            notifications.raiseNotification(apolloClient, 'CONNECTION_TIMEOUT')
          }
          observer.error(networkError)
        },
        complete: () => {
          if (!hasApplicationError) {
            // Completed successfully after retrying
            notifications.clearNotification(apolloClient)
          }
          observer.complete.bind(observer)()
        },
      })
    } catch (e) {
      observer.error(e)
    }
    return () => {
      if (subscription) subscription.unsubscribe()
    }
  })
})

成功重试时，Apollo-link @client突变

1 个答案: