Best Practice for context canceled.

[benkawecki]

Is there a good pattern for handling client disconnects? When a get a client cancelation (specifically client timeout or client disconnect) I typically end up having the server return a 500. This makes adding monitoring more difficult because we have alarms setup around 500.

For example, consider the following handler.

// Handler function that does many things
func GetWidget(ctx context.Context, input *Input) (*Output, error) {
    // validate user makes an external http api call and can have a context canceled error
    userInfo, err := validateUser(ctx)
    if err != nil {
        // return a 500 here
    }
    greeting, err := db.getWidget(input.id)
    if err != nil {
        // return 500 or other status code
    }

    // ...
    return resp, nil
}

The client could disconnect causing an err to be returned from either the validateUser function or the getWidget function. I could check the err issue against the client disconnect error, but overall this doesn't seem like an easy to abstract pattern.

My questions are:

1. What should the server do when the client disconnects (is there a way to effectively "cancel" the request within the huma handler?)
2. If the server should return a status code which one should it be?
3. What is the best abstraction to use to add this to a large number of handlers which may not have complicated logic to handle if the client disconnects mid request.