Event metadata missing in event object passed to serverless function

[pbochynski]

Description

Kyma delivers messages internally with CloudEvents specification. The metadata of the event is sent in HTTP request headers. Example:

  'ce-eventtypeversion': 'v1',
  'ce-id': 'c2b0aaa5-097e-4fd3-8bec-10e1d48c012e',
  'ce-knativearrivaltime': '2020-10-07T06:36:32.120434441Z',
  'ce-knativehistory': 'default-kne-trigger-kn-channel.default.svc.cluster.local',
  'ce-source': 'commerce',
  'ce-sourceid': 'commerce',
  'ce-specversion': '1.0',
  'ce-time': '2020-10-07T06:36:32.002Z',
  'ce-type': 'order.created',

But in the function different headers are expected and copied to the event object:

        const event = {
            'event-type': req.get('event-type'),
            'event-id': req.get('event-id'),
            'event-time': req.get('event-time'),
            'event-namespace': req.get('event-namespace'),
            data,
            'extensions': { request: req, response: res },
        };

Source: https://github.com/kubeless/runtimes/blob/e40586e968c4ecdb636b0da4c173647cfac16c2b/stable/nodejs/kubeless.js#L87-L94

Expected result

Event object in serverless function contains type, version and source of the event.

Actual result

Metadata fields contain undefined values:

  'event-type': undefined,
  'event-id': undefined,
  'event-time': undefined,
  'event-namespace': undefined

Steps to reproduce

Just send the event to the function with single line in the main body:

module.exports = { 
  main: function (event, context) {
    console.log(event)
  }
}

Workaround

You can access the CloudEvents metadata from incoming request headers:

console.log(event.extensions.request.headers)

[pbochynski]

The possible solutions:

1. send double headers (ce- and event-) from default-broker-filter to the function
2. modify kubeless runtime (contribute to the upstream project or fork)

I vote for option 2

[stale[bot]]

This issue has been automatically marked as stale due to the lack of recent activity. It will soon be closed if no further activity occurs. Thank you for your contributions.