NodeJS route with API request in it error - node.js

Question

I am writing a route that checks if a system app is online and then responds to the client with a simple 200 status ok, or a 404 status.
I'm using express and request to make the api call.
Route looks like this:
app.get('/status/keymgr', async (req, res, next) => {
try{
var endpoint = `http://${config.KeyManager.host}:${config.KeyManager.adminPort}/healthcheck`;
console.log(endpoint);
await request.get(endpoint, function(err, response, body){
if (!err && response.statusCode == 200){
res.send('OK');
}else{
res.status(404);
}
}).end();
}catch(error){
res.status(404);
}finally{
next();
}
});
For some reason, I am getting the following error:
uncaughtException: Can't set headers after they are sent.
I am guessing some kind of response is being sent to the browser before the route runs the res.send() or the res.status().
I can't figure out what's wrong here. Any idea??

Answer 1

AS #ndugger mentioned, the reason you are getting this exception is because request.get does not return a promise and hence await here is of no use. You have two options, either you use util.promisify or wrap your request under a new promise and resolve only when the callback finishes. Something like this
app.get('/status/keymgr', async (req, res, next) => {
var endpoint = `http://${config.KeyManager.host}:${config.KeyManager.adminPort}/healthcheck`;
console.log(endpoint);
try {
await new Promise((resolve, reject) => {
request.get(endpoint, function (err, response, body) {
if (!err && response.statusCode == 200) {
// res.send('OK');
resolve('OK');
} else {
reject('404')
// res.status(404);
}
});
});
res.send('OK');
} catch (err) {
res.status(404);
} finally {
next();
}
}