Expose return value - rest

Question

I have this piece of code that I am working on. To provide context, I am using an event source to stream an server sent event. Once I receive the data/response I want to pass that into my template(handlebars) view. The code below is a GET request in which I am trying to display the data returned from SSEvents.addEventListener.
method: 'GET',
path: '/students',
config: {
handler: (request, reply) => {
SSEvents.addEventListener('score', function(e) {
const data = JSON.parse(e.data);
}, false);
reply.view('students', {result: data});
},
description: "Endpoint lists all users that have received at least one test score.",
tags: ['api']
}
}
The issue with this code is the constant "data" is not available outside of the scope of the event listener. I need to find a way to expose the constant so that I can use it in reply.view('students', {result: data});
NOTE: I have tried adding "reply.view('students', {result: data});" within the event listener and it throws the following error: reply interface called twice.
Any help would be appreciated.
--Thanks!

Answer 1

It should be working like this. How long it takes your event source to produce an answer? Did you call the reply method twice? This is only one call.
handler: (request, reply) => {
SSEvents.addEventListener('score', function(e) {
const data = JSON.parse(e.data);
return reply.view('students', {
result: data
});
}, false);
},
description: "Endpoint lists all users that have received at least one test score.",
tags: ['api']
}