Express js middleware’s integration error with apollov4

[SwadipSinghoRoy]

I’m using Express js with @apollo/server & installed various middleware e.g: morgan, cors, cookieParser. But they didn’t executed.

// required dependencies here
..........
// Multiple schema configured file
const mergedSchema = require('./schemas/schemaConfig');

// Apollo server connection build
const apolloserver = new ApolloServer({
  schema: mergedSchema
})

// connection establishing
async function serverStart(server) {
  const PORT = process.env.PORT || 2080
  try {
    const { url } = await startStandaloneServer(server, {
      context: ({req, res}) => ({req, res}),
      listen: { port: PORT }
    })
    console.log(`# ~Server ready at: ${url}`);
    
    await mongoose.connect('mongodb://127.0.0.1:27017/DB-Name', {
      useNewUrlParser: true
    })
    mongoose.set("strictQuery", false);
    console.log("~Database connected.....");
  } catch (error) {
    console.log(error);
  }
}
serverStart(apolloserver);

// applied middlewares
app.use(
  morgan('dev'),
  cors(),
  express.json(),
  cookieParser()
)

Applied middleware doesn’t executing e.g: Didn’t executed morgan logger, cookieParser() etc. I tried expressMiddleware() with await server.start() instead of await startStandaloneServer() for managing middleware but facing another issues. When i’m going to await startStandaloneServer() approach server started & working, but middleware’s not working expectedly.

[glasser]

I'm a bit confused by your code snippet above. It doesn't match the text below.

startStandaloneServer is for when you don't want to tweak middleware with Express. If you want to do that, use expressMiddleware. It seems like you understand that, but the code snippet doesn't show what you tried to do with expressMiddleware.

Ideally, a full reproduction (try codesandbox.io) is helpful.

[SwadipSinghoRoy]

I applied as @glasser said. Sandbox implementation

[trevor-scheer]

The sandbox was broken, I fixed it (resolver -> resolvers).
It seems to be working, but I don't see any logs at all and I'm not sure why (not even console logs)

sandbox

[SwadipSinghoRoy]

Everything is working but don't print log so i can't understand what is happening actually. But log printed in my local device.

[trevor-scheer]

Ok. I ran your code locally and logging was fine. Maybe something with codesandbox.

The reason you're seeing the repeated logs seemingly after each query is because Explorer is querying your schema every second for changes. If you close Explorer or disable schema polling you'll notice the logs stop.

[SwadipSinghoRoy]

I don't understand, how explorer is querying automatically without send request from client side & how occured changes? Any suggested documentation/guideline for closing or disabling schema polling?

[trevor-scheer]

Explorer runs an introspection query which asks the graph about the schema itself. Explorer uses information about the schema to provide useful features like autocomplete.

To disable in the UI:
https://www.apollographql.com/docs/graphos/explorer/additional-features#local-development
To disable via config:
https://www.apollographql.com/docs/apollo-server/api/plugin/landing-pages#pollforschemaupdates

[trevor-scheer]

It does send a request, which you can see in the network tab in your browser.