install go2rtc on bob

installs_on_host/go2rtc/pkg/gopro/discovery.go

@@ -0,0 +1,43 @@
+package gopro
+
+import (
+	"net"
+	"net/http"
+	"regexp"
+)
+
+func Discovery() (urls []string) {
+	ints, err := net.Interfaces()
+	if err != nil {
+		return nil
+	}
+
+	// The socket address for USB connections is 172.2X.1YZ.51:8080
+	// https://gopro.github.io/OpenGoPro/http_2_0#socket-address
+	re := regexp.MustCompile(`^172\.2\d\.1\d\d\.`)
+
+	for _, itf := range ints {
+		addrs, err := itf.Addrs()
+		if err != nil {
+			continue
+		}
+
+		for _, addr := range addrs {
+			host := addr.String()
+			if !re.MatchString(host) {
+				continue
+			}
+
+			host = host[:11] + "51" // 172.2x.1xx.xxx
+			res, err := http.Get("http://" + host + ":8080/gopro/webcam/status")
+			if err != nil {
+				continue
+			}
+			_ = res.Body.Close()
+
+			urls = append(urls, host)
+		}
+	}
+
+	return
+}