Support loggging grpc status details

[devnev]

Problem

GRPC status messages on the wire are protos and include a field called details that allows further protos to be attached to the results - see https://github.com/grpc/grpc/blob/master/src/proto/grpc/status/status.proto#L91

Example of such an additions are in the error_details.proto file https://github.com/googleapis/googleapis/blob/master/google/rpc/error_details.proto

In particular, ErrorInfo can have extended error details and metadata that would be helpful to log

In v1, these could be extracted and added to the fields using the custom message producer option

Suggestion

Probably not a custom message producer like v1, but some kind of option to extend fields with error details or more generally with post-call fields

[johanbrandhorst]

Hi, thanks for your issue! I'm a little confused exactly what the proposal is here - are we talking about a new option, or some sort of automatic behaviour? Could you share an example of the API you'd like to see, what it would do, and alternatives you've considered? Thanks!

[kwargs]

I've encountered the same problem . I want to view error details in the logs since they contain useful information for debugging. However, I haven't found a clear way to configure a logging interceptor.

It would be great to have a logging.Option to control what error details are displayed in the logs. Something like this:

// ErrorToDetails is a function type that extracts details from an error.
// It allows logging of error details when needed.
type ErrorToDetails func(err error) Fields

I'm unsure whether enabling such a function by default is a good idea, as error details might contain private information.

[kwargs]

Hi,
Do you have any other API suggestions?
I'd be happy to prepare a pull request to implement them if that would be more convenient for you.

[johanbrandhorst]

I'd be happy to review a PR for this.