ApolloClient/Server authentication issue

[platocrat]

Issue

For the life of me, I cannot figure out what the issue is when I provide my auth secret keys to both my ApolloServer and ApolloClient scripts. On Fauna's forum, I saw that others do not have the same issue when authenticating with the same stack: Next.js, ApolloClient & Server, and FaunaDB.

Scripts

Here's what my client and server scripts look like:
pages/api/graphql.js:

const {
  ApolloServer,
  makeRemoteExecutableSchema,
  introspectSchema
} = require('apollo-server-micro')
const { createHttpLink } = require('apollo-link-http')
const fetch = require('isomorphic-fetch')

const link = createHttpLink({
  uri: 'https://graphql.fauna.com/graphql',
  fetch,
  headers: {
    Authorization: `Bearer ${process.env.SERVER_KEY}`
  }
})

async function schema() {
  const schema = makeRemoteExecutableSchema({
    schema: await introspectSchema(link),
    link
  })
}

const server = new ApolloServer({
  schema,
  introspection: true,
  playground: true,
})

export const config = {
  api: {
    bodyParser: false,
  },
}

const handler = server.createHandler({
  path: '/api/graphql',
})

export default handler

pages/api/client.js:

import { useMemo } from 'react'
import { ApolloClient, createHttpLink, InMemoryCache } from '@apollo/client'
import { setContext } from '@apollo/client/link/context'

const httpLink = createHttpLink({
  uri: 'https://graphql.fauna.com/graphql',
  credentials: 'same-origin',
  fetch,
})

const authLink = setContext((_, { headers }) => {
  return {
    headers: {
      ...headers,
      authorization: `Bearer ${process.env.FAUNA_ADMIN}`
    }
  }
})

console.log(process.env.FAUNA_ADMIN)

export const client = new ApolloClient({
  ssrMode: typeof window === 'undefined',
  link: authLink.concat(httpLink),
  cache: new InMemoryCache()
})

Current experiences and knowledge

GraphQL query

On the landing page, I attempt to make GET query with useQuery and return the error if there is one. The error returned from useQuery is:

Error: Invalid database secret.

Which to me makes no sense since I have tested new DBs and new sets of keys several times and all result in the same error.

ApolloClient and ApolloServer

Since useQuery relies on the client script, I assume there is an issue with the client script, hence the Invalid database secret error, but the issue is not with the database secret being used there. It must be with something else (because I have checked my keys, over and over again, and with tried even with new keys)

ApolloServer
When I navigate to the ApolloServer endpoint, it returns the following error:

Error: Unexpected error: Unable to resolve a valid GraphQLSchema.  Please file an issue with a reproduction of this error, if possible.

So, I'm not sure what I'm doing wrong.

Any help would be greatly appreciated!