When writing to console inside catch in a Google Cloud Function nothing is written - exception

Question

I have an array of work to do inside a Google Cloud Function. If I run the script locally it produces output to console but not in the cloud function.
// this is logged
console.error('An error');
for (var i=0; i<chunks.length; i++) {
const work = chunks[i].map(c => createOrUpdateTable(c, timestamp));
await Promise.all(work)
// this is not logged
.catch(e => console.error(e.message));
}
I've tried to put the catch inside the function and a whole lot of other things but same behaviour. How can I get the error to appear in the log?

Answer 1

According to the official documentation, you can emit an error from a Cloud Function to
Stackdriver Error Reporting:
// These WILL be reported to Stackdriver Error Reporting
console.error(new Error('I failed you'));
console.error('I failed you', new Error('I failed you too'));
throw new Error('I failed you'); // Will cause a cold start if not caught
// These will NOT be reported to Stackdriver Error Reporting
console.info(new Error('I failed you')); // Logging an Error object at the info level
console.error('I failed you'); // Logging something other than an Error object
throw 1; // Throwing something other than an Error object
callback('I failed you');
res.status(500).send('I failed you');
Reporting Errors

Answer 2

You should use a try/catch block as follows:
for (var i=0; i<chunks.length; i++) {
const work = chunks[i].map(c => createOrUpdateTable(c, timestamp));
try {
await Promise.all(work)
} catch (e) {
console.error(e.message));
return { error: err }
}
}

Answer 3

I have reproduced the issue and I get the error logged but differently.
First function:
exports.helloError = (data, context, callback) => {
// [START functions_helloworld_error]
// These WILL be reported to Stackdriver Error Reporting
console.error(new Error('I failed you'));
console.error('I failed you', new Error('I failed you too'));
throw new Error('I failed you'); // Will cause a cold start if not caught
// [END functions_helloworld_error]
};
In stackdriver logging it appears as an error !!
severity: "ERROR"
textPayload: "Error: I failed you
at exports.helloError (/srv/index.js:4:17)
at /worker/worker.js:783:7
at /worker/worker.js:766:11
And with the second function:
exports.helloError = (data, context, callback) => {
try{
throw new Error('I failed you'); // Will cause a cold start if not caught
}catch(e){
console.log(e.message);
};
};
It is reported as an INFO λ
severity: "INFO"
textPayload: "I failed you"
I suspect that as the error is handled in the second one, the function is working as expected, so it will not be reported as an error but information of the performance.