support regex and player name sniff

e2e/e2e_test.go

@@ -63,6 +63,37 @@ func TestRoundTrip(t *testing.T) {
 	}
 }
 
+// TestRegexPatternMatch verifies a wildcard regex pattern routes a matching
+// player (whole-hostname, case-insensitive) and drops a non-matching one, and
+// that the client maps the hub-echoed pattern back to its destination.
+func TestRegexPatternMatch(t *testing.T) {
+	const psk = "e2e-regex"
+	port := freePort(t)
+	hubAddr := fmt.Sprintf("127.0.0.1:%d", port)
+	startHub(t, port, psk)
+	dest := newMockDest(t, modeEcho)
+	startClient(t, hubAddr, psk, 2, []client.Mapping{
+		{Pattern: `mc\d+\.local`, Destination: dest.addr},
+	})
+
+	// Matches the regex (digit wildcard, mixed case); the whole hostname matches.
+	pc := dialPlayer(t, hubAddr, "MC7.Local")
+	defer pc.Close()
+	playerEcho(t, pc, []byte("regex hello"))
+	ev := dest.waitEvent(t, 5*time.Second)
+	if ev.handshakeAddr != "MC7.Local" {
+		t.Fatalf("destination saw handshake address %q, want verbatim %q", ev.handshakeAddr, "MC7.Local")
+	}
+
+	// A host that does not fully match the pattern is dropped ('\d+' needs a digit).
+	pc2 := dialPlayer(t, hubAddr, "mc.local")
+	defer pc2.Close()
+	_ = pc2.SetReadDeadline(time.Now().Add(3 * time.Second))
+	if _, err := pc2.Read(make([]byte, 16)); err == nil {
+		t.Fatalf("expected the hub to drop a host that does not match the regex")
+	}
+}
+
 // TestLargeTransfer pushes a multi-megabyte payload both ways to exercise mux
 // framing and back-pressure.
 func TestLargeTransfer(t *testing.T) {