React native Apollo setContext无法从服务器保存令牌

我想实现apollo链接上下文/react native/graphql，但apollo setContext不保存accessToken。如果我用console.log检查它，我会得到未定义。在我从服务器获取令牌之前，看起来像是setContext调用。因此setContext无法及时保存令牌。谁能帮帮我吗

App.js

import React from 'react'
import { ApolloProvider } from 'react-apollo'
import { ApolloProvider as ApolloHooksProvider } from 'react-apollo-hooks'
import { ApolloClient } from 'apollo-client'
import { createHttpLink } from 'apollo-link-http'
import { setContext } from 'apollo-link-context'
import { InMemoryCache } from 'apollo-cache-inmemory'
import * as Keychain from 'react-native-keychain'
import AppNavigator from './AppNavigator'

const httpLink = createHttpLink({
  uri: 'http://localhost:4000'
})

const authLink = setContext(async (_, { headers }) => {
  const tokens = await Keychain.getGenericPassword()
  const accessToken = tokens.accessToken
  console.log('accessTokenSetContext', accessToken)
  return {
    headers: {
      ...headers,
      authorization: accessToken ? `Bearer ${accessToken}` : ''
    }
  }
})

const client = new ApolloClient({
  link: authLink.concat(httpLink),
  cache: new InMemoryCache(),
  connectToDevTools: true
})

const App = () => {
  return (
    <ApolloProvider client={client}>
      <ApolloHooksProvider client={client}>
        <AppNavigator />
      </ApolloHooksProvider>
    </ApolloProvider>
  )
}

export default App

从“React”导入React
从'react apollo'导入{ApolloProvider}
从'react apollo hooks'导入{ApolloProvider as ApollooksProvider}
从“apollo客户端”导入{apollo客户端}
从“apollo链接http”导入{createHttpLink}
从“apollo链接上下文”导入{setContext}
从'apollo cache inmemory'导入{InMemoryCache}
从“react native Keychain”导入*作为密钥链
从“./AppNavigator”导入AppNavigator
const httpLink=createHttpLink({
uri:'http://localhost:4000'
})
const authLink=setContext（异步（{headers}）=>{
const tokens=wait Keychain.getGenericPassword（）
const accessToken=tokens.accessToken
log（'accessTokenSetContext'，accessToken）
返回{
标题：{
…标题，
授权：accessToken？`Bearer${accessToken}`:''
}
}
})
const客户端=新客户端({
链接：authLink.concat（httpLink），
缓存：新的InMemoryCache（），
connectToDevTools:true
})
常量应用=（）=>{
返回(
)
}
导出默认应用程序