fix/DF-531: Error stack traces

[davidjamesstone]

This should fix missing stack traces when an unhandled exception is encountered in a route handler.

More info

Hi all 👋

I'm looking for a way to capture and log stack traces when an unhandled exception is encountered in a route.

I have a generic onPreResponse handler for error logging that looks something like:

server.ext('onPreResponse', (request, h) => {
  const response = request.response

  if (Boom.isBoom(response)) {
    // Stack trace is undefined for unhandled system errors
    console.log(response.stack)
    
    return h.response({}).code(500)
  }
  
  return h.continue
})

If I have a route that generates an unhandled error e.g.

{
    method: 'GET',
    path: '/generate-error',
    async handler(request, h) {
      const o = undefined
      
      // Generate a TypeError
      const val = o.val
      
      return { some: 'thing' }
    }
}

The response.stack in onPreResponse is always undefined.

Stepping through the code it is because of this line in toolkit.js uses Boom.badImplementation which is stripping out the stack here in Hoek.clone

Is this by design? Has anyone overcome this and found a way to access the err.stack in an onPreResponse for unhandled system errors?

TIA

djs — 11:25 AM
Hoek is stripping it here when cloning the error, it gets the descriptor with key "stack" and redefines the property on the cloned error Object.defineProperty(newObj, key, descriptor) but the descriptor value is lost

djs — 12:16 PM
Looking at the most recent version of Hoek (11.0.7) it looks like stack now gets special handling (in node 21+). If I force Boom to use Hoek version 11.0.7, I see a stack trace in onPreResponse.

Latest Boom uses Hoek@^11.0.2.

Ok, I've now just seen this issue.
Given hapijs/hoek#390 is now merged, can we get a new version of Boom published? Or is it awaiting this?

djs — 1:12 PM
Node was installing hoek@11.0.2 for boom. I fixed this by adding an explicit dependency to hoek@11.0.7 in my package.json.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[alexluckett]

good spot, wonder why we never spotted this unreachable code before!