pkg/server/middleware: fix invalid project ID errors in logs

don't attempt to parse an invalid public project ID like "-"
if no credentials are present, or if there's an empty string
returned from authservice. If authservice produces an empty
UUID (string as all zeros) then it's still valid and won't
cause any problems.

Change-Id: I6ae5a14d0500397f312694b3afc7a8ce41e95c29

pkg/server/middleware/access_log.go

@@ -65,14 +65,17 @@ func AccessLog(log *zap.Logger, p *accesslogs.Processor, config AccessLogConfig)
 
 			h.ServeHTTP(w, r)
 
-			logEntry := extractLogEntry(r, rw, startTime, gl)
-			credentials := GetAccess(r.Context())
 			var publicProjectID string
-			if credentials == nil {
-				publicProjectID = "-"
-			} else {
+			credentials := GetAccess(r.Context())
+			if credentials != nil {
 				publicProjectID = credentials.PublicProjectID
 			}
+
+			if publicProjectID == "" {
+				return
+			}
+
+			logEntry := extractLogEntry(r, rw, startTime, gl)
 			processLogEntry(log, p, config, publicProjectID, gl.BucketName, &logEntry)
 		}))
 	}
@@ -215,7 +218,9 @@ func extractLogEntry(r *http.Request, rw whmon.ResponseWriter, startTime time.Ti
 func processLogEntry(log *zap.Logger, p *accesslogs.Processor, config AccessLogConfig, publicProjectID, bucketName string, logEntry *accesslogs.S3AccessLogEntry) {
 	parsedPublicProjectID, err := uuid.FromString(publicProjectID)
 	if err != nil {
-		log.Error("Error parsing public project ID from authservice", zap.Error(err))
+		log.Error("Error parsing public project ID from authservice",
+			zap.Error(err),
+			zap.String("publicProjectID", publicProjectID))
 		return
 	}