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HTTP Error Responses

Now that we can pass logging context upstream, we can improve HTTP error logging. Wouldn't it be useful to include stack traces whenever we log an error status?

We'll start by adding a small helper that wraps http.Error. It still sends the HTTP response, but first stores the error in LogContext (if present) so request logs can include it:

func httpError(ctx context.Context, w http.ResponseWriter, status int, err error) {
	if logCtx, ok := ctx.Value(logContextKey).(*LogContext); ok {
		logCtx.Error = err
	}
	http.Error(w, err.Error(), status)
}

Now request logs for error responses include full error details (including stack traces when present). How handy is that?

Assignment

Capture HTTP response errors in request logs.

Add an Error error field to your LogContext struct.
Create an httpError helper function (as shown above) that accepts a context.Context, http.ResponseWriter, status code, and error. It should stash the error in the LogContext (if present) and then call http.Error to actually send the response.
Replace existing http.Error calls in your handlers and auth middleware with the new httpError helper.

Pass lowercase internal messages (for example, unauthorized and internal server error) so logs stay consistent. That's the Go standard.
Update your requestLogger middleware to include the error from the log context in an "error" attribute if it exists, so each response error is logged once.

Restart your server with LINKO_LOG_FILE=linko.access.log set:

LINKO_LOG_FILE=linko.access.log go run .

Run and submit the CLI tests from the root of the Linko repo.