Reduce the amount of useless data in request’s log

I tried to have a log line that uses the “common” format from Apache,
because i thought that it would help me reuse regexps i have defined for
fail2ban filters and such.

However, it makes no much sense.

For once, i was repeating the date and time: log.Printf already does
that for me.

And, second, i do not need that data in Numerus’ log because i always
run it behind a proxy that _has_ a “common”-formatted log file, so
there is no need for me to repeat all that data again.

What i need is the IP, to know whether remotedAdd() function works as
expected; the method, to check that the override does its job; the path,
to know what resource the browser requested; the response status code,
so that i do not need to open the browser console for that; the response
size, to keep on eye that i do not return a lot of data; and the
total response time, to realize how long my unoptimized SQL queries
slows the application down.

The rest, Apache should do its job and record it in its log file for
fail2ban and whatever i need the logs for in the future.

pkg/logger.go

@@ -41,20 +41,12 @@ func Logger(handler http.Handler) http.Handler {
 		if statusCode == 0 {
 			statusCode = http.StatusOK
 		}
-		referer := r.Referer()
-		if referer == "" {
-			referer = "-"
-		}
-		stdout.Printf("HTTP - %s - - [%s] \"%s %s %s\" %d %d \"%s\" \"%s\" %s\n",
+		stdout.Printf("HTTP - %s %s \"%s\" %d %d %s\n",
 			remoteAddr(r),
-			t.Format("02/Jan/2006:15:04:05 -0700"),
 			r.Method,
 			r.URL.Path,
-			r.Proto,
 			statusCode,
 			logger.responseSize,
-			referer,
-			r.UserAgent(),
 			time.Since(t),
 		)