Keep things generic for the time being. Refactor for simplicity.

goupnp.go

@@ -1,122 +1,98 @@
+// goupnp is an implementation of a client for UPnP devices.
 package goupnp
 
 import (
 	"encoding/xml"
 	"fmt"
-	"log"
 	"net/http"
+	"net/url"
 )
 
+// Non-exhaustive set of UPnP service types.
 const (
-	// Search Target for InternetGatewayDevice.
+	ServiceTypeLayer3Forwarding         = "urn:schemas-upnp-org:service:Layer3Forwarding:1"
-	SearchTargetIGD = "urn:schemas-upnp-org:device:InternetGatewayDevice:1"
+	ServiceTypeWANCommonInterfaceConfig = "WANCommonInterfaceConfig:1"
+	// WANPPPConnection is typically useful with regard to the external IP and
+	// port forwarding.
+	ServiceTypeWANPPPConnection = "WANPPPConnection:1"
 )
 
-// DiscoverIGD attempts to find Internet Gateway Devices.
+// Non-exhaustive set of UPnP device types.
-//
+const (
-// TODO: Fix implementation to discover multiple. Currently it will find a
+	// Device type for InternetGatewayDevice.
-// maximum of one.
+	// http://upnp.org/specs/gw/upnp-gw-internetgatewaydevice-v1-device.pdf
-func DiscoverIGD() ([]*IGD, error) {
+	DeviceTypeInternetGatewayDevice = "urn:schemas-upnp-org:device:InternetGatewayDevice:1"
+)
+
+type ContextError struct {
+	Context string
+	Err     error
+}
+
+func (err ContextError) Error() string {
+	return fmt.Sprintf("%s: %v", err.Context, err.Err)
+}
+
+type MaybeRootDevice struct {
+	Root *RootDevice
+	Err  error
+}
+
+// DiscoverDevices attempts to find targets of the given type. searchTarget is
+// typically a value from a DeviceType* constant. An error is returned for
+// errors while attempting to send the query. An error or RootDevice is
+// returned for each discovered service.
+func DiscoverDevices(searchTarget string) ([]MaybeRootDevice, error) {
 	httpu, err := NewHTTPUClient()
 	if err != nil {
 		return nil, err
 	}
-	responses, err := SSDPRawSearch(httpu, SearchTargetIGD, 2, 3)
+	defer httpu.Close()
+	responses, err := SSDPRawSearch(httpu, string(searchTarget), 2, 3)
+	if err != nil {
+		return nil, err
+	}
 
-	results := make([]*IGD, 0, len(responses))
+	results := make([]MaybeRootDevice, len(responses))
-	for _, response := range responses {
+	for i, response := range responses {
+		maybe := &results[i]
 		loc, err := response.Location()
 		if err != nil {
-			log.Printf("goupnp: unexpected bad location from search: %v", err)
+			maybe.Err = ContextError{"unexpected bad location from search", err}
 			continue
 		}
-		igd, err := requestIgd(loc.String())
+		locStr := loc.String()
+		root := new(RootDevice)
+		if err := requestXml(locStr, DeviceXMLNamespace, root); err != nil {
+			maybe.Err = ContextError{fmt.Sprintf("error requesting root device details from %q", locStr), err}
+			continue
+		}
+		urlBase, err := url.Parse(root.URLBaseStr)
 		if err != nil {
-			log.Printf("goupnp: error requesting IGD: %v", err)
+			maybe.Err = ContextError{fmt.Sprintf("error parsing URLBase %q from %q: %v", root.URLBaseStr, locStr), err}
 			continue
 		}
-		results = append(results, igd)
+		root.SetURLBase(urlBase)
+		maybe.Root = root
 	}
 
 	return results, nil
 }
 
-// IGD defines the interface for an Internet Gateway Device.
+func requestXml(url string, defaultSpace string, doc interface{}) error {
-type IGD struct {
+	resp, err := http.Get(url)
-	xml xmlRootDevice
-}
-
-func requestIgd(serviceUrl string) (*IGD, error) {
-	resp, err := http.Get(serviceUrl)
 	if err != nil {
-		return nil, err
+		return err
 	}
 	defer resp.Body.Close()
 
 	if resp.StatusCode != 200 {
-		return nil, fmt.Errorf("goupnp: got response status %s from IGD at %q",
+		return fmt.Errorf("goupnp: got response status %s from %q",
-			resp.Status, serviceUrl)
+			resp.Status, url)
 	}
 
 	decoder := xml.NewDecoder(resp.Body)
-	decoder.DefaultSpace = deviceXmlNs
+	decoder.DefaultSpace = defaultSpace
-	var xml xmlRootDevice
-	if err = decoder.Decode(&xml); err != nil {
-		return nil, err
-	}
-	log.Printf("%+v", xml)
 
-	return &IGD{xml}, nil
+	return decoder.Decode(doc)
-}
-
-func (igd *IGD) Device() *Device {
-	return &Device{
-		igd.xml.URLBase,
-		igd.xml.Device,
-	}
-}
-
-func (igd *IGD) String() string {
-	return fmt.Sprintf("IGD{UDN: %q friendlyName: %q}",
-		igd.xml.Device.UDN, igd.xml.Device.FriendlyName)
-}
-
-type Device struct {
-	urlBase string
-	xml     xmlDevice
-}
-
-func (device *Device) String() string {
-	return fmt.Sprintf("Device{friendlyName: %q}", device.xml.FriendlyName)
-}
-
-func (device *Device) Devices() []*Device {
-	devices := make([]*Device, len(device.xml.Devices))
-	for i, childXml := range device.xml.Devices {
-		devices[i] = &Device{
-			device.urlBase,
-			childXml,
-		}
-	}
-	return devices
-}
-
-func (device *Device) Services() []*Service {
-	srvs := make([]*Service, len(device.xml.Services))
-	for i, childXml := range device.xml.Services {
-		srvs[i] = &Service{
-			device.urlBase,
-			childXml,
-		}
-	}
-	return srvs
-}
-
-type Service struct {
-	urlBase string
-	xml     xmlService
-}
-
-func (srv *Service) String() string {
-	return fmt.Sprintf("Service{serviceType: %q}", srv.xml.ServiceType)
 }

httpu.go

@@ -67,7 +67,7 @@ func (httpu *HTTPUClient) Do(req *http.Request, timeout time.Duration, numSends
 			return nil, fmt.Errorf("httpu: wrote %d bytes rather than full %d in request",
 				n, len(requestBuf.Bytes()))
 		}
-		time.Sleep(10 * time.Millisecond)
+		time.Sleep(5 * time.Millisecond)
 	}
 
 	// Await responses until timeout.

xml.go

@@ -4,25 +4,35 @@ package goupnp
 
 import (
 	"encoding/xml"
+	"fmt"
+	"net/url"
 )
 
 const (
-	deviceXmlNs = "urn:schemas-upnp-org:device-1-0"
+	DeviceXMLNamespace = "urn:schemas-upnp-org:device-1-0"
 )
 
-type xmlRootDevice struct {
+type RootDevice struct {
+	URLBase     *url.URL    `xml:"-"`
 	Name        xml.Name    `xml:"root`
-	SpecVersion xmlSpecVersion `xml:"specVersion"`
+	SpecVersion SpecVersion `xml:"specVersion"`
-	URLBase     string         `xml:"URLBase"`
+	URLBaseStr  string      `xml:"URLBase"`
-	Device      xmlDevice      `xml:"device"`
+	Device      *Device     `xml:"device"`
 }
 
-type xmlSpecVersion struct {
+func (root *RootDevice) SetURLBase(urlBase *url.URL) {
+	root.URLBase = urlBase
+	root.URLBaseStr = urlBase.String()
+	root.Device.SetURLBase(urlBase)
+}
+
+type SpecVersion struct {
 	Major int32 `xml:"major"`
 	Minor int32 `xml:"minor"`
 }
 
-type xmlDevice struct {
+type Device struct {
+	URLBase          *url.URL   `xml:"-"`
 	DeviceType       string     `xml:"deviceType"`
 	FriendlyName     string     `xml:"friendlyName"`
 	Manufacturer     string     `xml:"manufacturer"`
@@ -34,15 +44,29 @@ type xmlDevice struct {
 	SerialNumber     string     `xml:"serialNumber"`
 	UDN              string     `xml:"UDN"`
 	UPC              string     `xml:"UPC,omitempty"`
-	Icons            []xmlIcon    `xml:"iconList>icon,omitempty"`
+	Icons            []*Icon    `xml:"iconList>icon,omitempty"`
-	Services         []xmlService `xml:"serviceList>service,omitempty"`
+	Services         []*Service `xml:"serviceList>service,omitempty"`
-	Devices          []xmlDevice  `xml:"deviceList>device,omitempty"`
+	Devices          []*Device  `xml:"deviceList>device,omitempty"`
 
 	// Extra observed elements:
 	PresentationURL string `xml:"presentationURL"`
 }
 
-type xmlIcon struct {
+func (device *Device) SetURLBase(urlBase *url.URL) {
+	device.URLBase = urlBase
+	for _, srv := range device.Services {
+		srv.SetURLBase(urlBase)
+	}
+	for _, child := range device.Devices {
+		child.SetURLBase(urlBase)
+	}
+}
+
+func (device *Device) String() string {
+	return fmt.Sprintf("Device ID %s : %s (%s)", device.UDN, device.DeviceType, device.FriendlyName)
+}
+
+type Icon struct {
 	Mimetype string `xml:"mimetype"`
 	Width    int32  `xml:"width"`
 	Height   int32  `xml:"height"`
@@ -50,10 +74,19 @@ type xmlIcon struct {
 	URL      string `xml:"url"`
 }
 
-type xmlService struct {
+type Service struct {
+	URLBase     *url.URL `xml:"-"`
 	ServiceType string   `xml:"serviceType"`
 	ServiceId   string   `xml:"serviceId"`
 	SCPDURL     string   `xml:"SCPDURL"`
 	ControlURL  string   `xml:"controlURL"`
 	EventSubURL string   `xml:"eventSubURL"`
 }
+
+func (srv *Service) SetURLBase(urlBase *url.URL) {
+	srv.URLBase = urlBase
+}
+
+func (srv *Service) String() string {
+	return fmt.Sprintf("Service ID %s : %s", srv.ServiceId, srv.ServiceType)
+}