Styjun

I'm having trouble finding out why the following function finished with a status code of 304 rather then sending the 200 response. The documents update as required, but I want to get the correct status code.

const firestoreInstance = admin.firestore();

export async function onTwitchGiveawayPostback(req, res) 
 const reward = 1;

 const userName = await utils.getParameterByName('name', req.originalUrl);

 if (!userName) throw new Error('User Display Name is not set on REQLoot :('); 

 const displayNameDocPath = firestoreInstance.collection('displayNames').doc(userName);

 return displayNameDocPath.get().then(snapshot => snapshot.data()).then(displayNameDocDetails => 
 if (!displayNameDocDetails) 
 res.status(200).send('User Display Name: ' + userName + ' is not set on REQLoot :(');
 return Promise.resolve('Ok');
 else 
 const uid = displayNameDocDetails.uid;

 const staminaEntryDoc = firestoreInstance.collection(utils.API_URLS.userStaminaBalanceSheet + '/' + uid + '/entries').doc();
 const userDocPath = firestoreInstance.collection('users').doc(uid);

 const promises = [];
 promises.push(
 userDocPath.get(),
 );

 return Promise.all(promises).then((snapshots) => 
 return Promise.all(snapshots.map((doc) => 
 return doc.data();
 )).then(data => 
 const userDocDetails = data[0];

 const serverTimestamp = admin.firestore.Timestamp.now();

 const batch = firestoreInstance.batch();

 const staminaBalanceSheetDescription = 'winner';
 const staminaPrev = userDocDetails.stamina;
 const staminaNew = staminaPrev + reward;

 batch.update(userDocPath, 
 stamina: staminaNew,
 updatedAt: serverTimestamp,
 );

 // Update the User's stamina balance sheet
 batch.set(staminaEntryDoc, 
 description: staminaBalanceSheetDescription,
 stamina: 
 previous: staminaPrev,
 new: staminaNew,
 ,
 staminaAmount: reward,
 updatedAt: serverTimestamp,
 );

 return batch.commit();
 )
 .then(() => 
 res.status(200).send(userName + ' won some stamina!');
 )
 .catch((err) => 
 console.error(err)
 return err;
 );
 )
 
 )
 .catch(err => console.log(err))

Other posts have mentioned that the function always needs to return a Promise, but I think I've added them where necessary. What am I missing that is preventing a normal 200 response?

The issue was CORS.

The function was executing and updating firestore, but returning a 304 status code and not sending the string payload. Updating the function with the following line:

res.set('Access-Control-Allow-Origin', '*');

Allowed for a 200 status code and proper string being sent on completion.