Simplify filter flag handling. Rename Filter interface.

flags.go

@@ -45,8 +45,8 @@ var symbolLength = flag.Int("symbollength", 72, "symbol length in samples, see -
 var decimation = flag.Int("decimation", 1, "integer decimation factor, keep every nth sample")
 
 var timeLimit = flag.Duration("duration", 0, "time to run for, 0 for infinite, ex. 1h5m10s")
-var meterID UintMap
-var meterType UintMap
+var meterID MeterIDFilter
+var meterType MeterTypeFilter
 
 var unique = flag.Bool("unique", false, "suppress duplicate messages from each meter")
 
@@ -58,8 +58,8 @@ var quiet = flag.Bool("quiet", false, "suppress printing state information at st
 var single = flag.Bool("single", false, "one shot execution")
 
 func RegisterFlags() {
-	meterID = make(UintMap)
-	meterType = make(UintMap)
+	meterID = MeterIDFilter{make(UintMap)}
+	meterType = MeterTypeFilter{make(UintMap)}
 
 	flag.Var(meterID, "filterid", "display only messages matching an id in a comma-separated list of ids.")
 	flag.Var(meterType, "filtertype", "display only messages matching a type in a comma-separated list of types.")
@@ -171,16 +171,20 @@ func (m UintMap) Set(value string) error {
 	return nil
 }
 
-type MeterIDFilter UintMap
+type MeterIDFilter struct {
+	UintMap
+}
 
 func (m MeterIDFilter) Filter(msg parse.Message) bool {
-	return m[uint(msg.MeterID())]
+	return m.UintMap[uint(msg.MeterID())]
 }
 
-type MeterTypeFilter UintMap
+type MeterTypeFilter struct {
+	UintMap
+}
 
 func (m MeterTypeFilter) Filter(msg parse.Message) bool {
-	return m[uint(msg.MeterType())]
+	return m.UintMap[uint(msg.MeterType())]
 }
 
 type UniqueFilter map[uint][]byte

parse/parse.go

@@ -78,9 +78,9 @@ func (msg LogMessage) Record() (r []string) {
 	return r
 }
 
-type FilterChain []Filter
+type FilterChain []MessageFilter
 
-func (fc *FilterChain) Add(filter Filter) {
+func (fc *FilterChain) Add(filter MessageFilter) {
 	*fc = append(*fc, filter)
 }
 
@@ -90,14 +90,14 @@ func (fc FilterChain) Match(msg Message) bool {
 	}
 
 	for _, filter := range fc {
-		if !filter.Filter(msg) {
+		if !filter.MessageFilter(msg) {
 			return false
 		}
 	}
 
 	return true
 }
 
-type Filter interface {
+type MessageFilter interface {
 	Filter(Message) bool
 }

recv.go

@@ -85,9 +85,9 @@ func (rcvr *Receiver) NewReceiver() {
 		case "unique":
 			rcvr.fc.Add(NewUniqueFilter())
 		case "filterid":
-			rcvr.fc.Add(MeterIDFilter(meterID))
+			rcvr.fc.Add(meterID)
 		case "filtertype":
-			rcvr.fc.Add(MeterTypeFilter(meterType))
+			rcvr.fc.Add(meterType)
 		default:
 			fmt.Println(f.Name)
 		}