fix(broker): empty pattern if bridge-list is empty

i.e. if no bridge list file is provided, the relay pattern
would not get set.

AFAIK this is not a breaking change because the broker
can't be used as a library, unlike client and server.

broker/broker.go

@@ -53,7 +53,11 @@ func (ctx *BrokerContext) GetBridgeInfo(fingerprint bridgefingerprint.Fingerprin
 	return ctx.bridgeList.GetBridgeInfo(fingerprint)
 }
 
-func NewBrokerContext(metricsLogger *log.Logger) *BrokerContext {
+func NewBrokerContext(
+	metricsLogger *log.Logger,
+	allowedRelayPattern,
+	presumedPatternForLegacyClient string,
+) *BrokerContext {
 	snowflakes := new(SnowflakeHeap)
 	heap.Init(snowflakes)
 	rSnowflakes := new(SnowflakeHeap)
@@ -75,12 +79,14 @@ func NewBrokerContext(metricsLogger *log.Logger) *BrokerContext {
 	bridgeListHolder.LoadBridgeInfo(bytes.NewReader([]byte(DefaultBridges)))
 
 	return &BrokerContext{
-		snowflakes:           snowflakes,
-		restrictedSnowflakes: rSnowflakes,
-		idToSnowflake:        make(map[string]*Snowflake),
-		proxyPolls:           make(chan *ProxyPoll),
-		metrics:              metrics,
-		bridgeList:           bridgeListHolder,
+		snowflakes:                     snowflakes,
+		restrictedSnowflakes:           rSnowflakes,
+		idToSnowflake:                  make(map[string]*Snowflake),
+		proxyPolls:                     make(chan *ProxyPoll),
+		metrics:                        metrics,
+		bridgeList:                     bridgeListHolder,
+		allowedRelayPattern:            allowedRelayPattern,
+		presumedPatternForLegacyClient: presumedPatternForLegacyClient,
 	}
 }
 
@@ -161,12 +167,10 @@ func (ctx *BrokerContext) AddSnowflake(id string, proxyType string, natType stri
 	return snowflake
 }
 
-func (ctx *BrokerContext) InstallBridgeListProfile(reader io.Reader, relayPattern, presumedPatternForLegacyClient string) error {
+func (ctx *BrokerContext) InstallBridgeListProfile(reader io.Reader) error {
 	if err := ctx.bridgeList.LoadBridgeInfo(reader); err != nil {
 		return err
 	}
-	ctx.allowedRelayPattern = relayPattern
-	ctx.presumedPatternForLegacyClient = presumedPatternForLegacyClient
 	return nil
 }
 
@@ -244,14 +248,14 @@ func main() {
 
 	metricsLogger := log.New(metricsFile, "", 0)
 
-	ctx := NewBrokerContext(metricsLogger)
+	ctx := NewBrokerContext(metricsLogger, allowedRelayPattern, presumedPatternForLegacyClient)
 
 	if bridgeListFilePath != "" {
 		bridgeListFile, err := os.Open(bridgeListFilePath)
 		if err != nil {
 			log.Fatal(err.Error())
 		}
-		err = ctx.InstallBridgeListProfile(bridgeListFile, allowedRelayPattern, presumedPatternForLegacyClient)
+		err = ctx.InstallBridgeListProfile(bridgeListFile)
 		if err != nil {
 			log.Fatal(err.Error())
 		}

broker/snowflake-broker_test.go

@@ -89,7 +89,7 @@ func TestBroker(t *testing.T) {
 
 	Convey("Context", t, func() {
 		buf := new(bytes.Buffer)
-		ctx := NewBrokerContext(log.New(buf, "", 0))
+		ctx := NewBrokerContext(log.New(buf, "", 0), "", "")
 		i := &IPC{ctx}
 
 		Convey("Adds Snowflake", func() {
@@ -503,7 +503,7 @@ client-sqs-ips
 	})
 
 	Convey("End-To-End", t, func() {
-		ctx := NewBrokerContext(NullLogger())
+		ctx := NewBrokerContext(NullLogger(), "", "")
 		i := &IPC{ctx}
 
 		Convey("Check for client/proxy data race", func() {
@@ -656,7 +656,7 @@ func TestSnowflakeHeap(t *testing.T) {
 func TestInvalidGeoipFile(t *testing.T) {
 	Convey("Geoip", t, func() {
 		// Make sure things behave properly if geoip file fails to load
-		ctx := NewBrokerContext(NullLogger())
+		ctx := NewBrokerContext(NullLogger(), "", "")
 		if err := ctx.metrics.LoadGeoipDatabases("invalid_filename", "invalid_filename6"); err != nil {
 			log.Printf("loading geo ip databases returned error: %v", err)
 		}
@@ -670,7 +670,7 @@ func TestMetrics(t *testing.T) {
 	Convey("Test metrics...", t, func() {
 		done := make(chan bool)
 		buf := new(bytes.Buffer)
-		ctx := NewBrokerContext(log.New(buf, "", 0))
+		ctx := NewBrokerContext(log.New(buf, "", 0), "", "")
 		i := &IPC{ctx}
 
 		err := ctx.metrics.LoadGeoipDatabases("test_geoip", "test_geoip6")

broker/sqs_test.go

@@ -22,7 +22,7 @@ func TestSQS(t *testing.T) {
 
 	Convey("Context", t, func() {
 		buf := new(bytes.Buffer)
-		ipcCtx := NewBrokerContext(log.New(buf, "", 0))
+		ipcCtx := NewBrokerContext(log.New(buf, "", 0), "", "")
 		i := &IPC{ipcCtx}
 
 		var logBuffer bytes.Buffer