feat: 重建 ONVIF 与 RTSP 视频接入 (#66)

Sense/server/app/sense/onvif/parser.go

@@ -0,0 +1,75 @@
+package onvif
+
+import (
+	"encoding/xml"
+	"errors"
+	"io"
+	"strings"
+)
+
+var ErrInvalidResponse = errors.New("ONVIF 返回内容无法识别")
+
+type profileEnvelope struct {
+	Profiles []struct {
+		Token   string `xml:"token,attr"`
+		Name    string `xml:"Name"`
+		Encoder struct {
+			Encoding   string `xml:"Encoding"`
+			Resolution struct {
+				Width  int `xml:"Width"`
+				Height int `xml:"Height"`
+			} `xml:"Resolution"`
+		} `xml:"VideoEncoderConfiguration"`
+	} `xml:"Body>GetProfilesResponse>Profiles"`
+}
+
+func parseProfiles(data []byte) ([]Profile, error) {
+	var envelope profileEnvelope
+	if err := xml.Unmarshal(data, &envelope); err != nil || len(envelope.Profiles) == 0 || len(envelope.Profiles) > 128 {
+		return nil, ErrInvalidResponse
+	}
+	result := make([]Profile, 0, len(envelope.Profiles))
+	for _, p := range envelope.Profiles {
+		if strings.TrimSpace(p.Token) == "" || len(p.Token) > 255 || len([]rune(p.Name)) > 255 || p.Encoder.Resolution.Width <= 0 || p.Encoder.Resolution.Width > 32768 || p.Encoder.Resolution.Height <= 0 || p.Encoder.Resolution.Height > 32768 || len(p.Encoder.Encoding) > 32 {
+			continue
+		}
+		result = append(result, Profile{Token: p.Token, Name: p.Name, Width: p.Encoder.Resolution.Width, Height: p.Encoder.Resolution.Height, Encoding: p.Encoder.Encoding})
+	}
+	if len(result) == 0 {
+		return nil, ErrInvalidResponse
+	}
+	return result, nil
+}
+
+func parseElement(data []byte, parent, name string) (string, error) {
+	decoder := xml.NewDecoder(strings.NewReader(string(data)))
+	depth := 0
+	for {
+		token, err := decoder.Token()
+		if err != nil {
+			if errors.Is(err, io.EOF) {
+				return "", ErrInvalidResponse
+			}
+			return "", ErrInvalidResponse
+		}
+		switch value := token.(type) {
+		case xml.StartElement:
+			if parent == "" || value.Name.Local == parent {
+				if value.Name.Local == parent {
+					depth++
+				}
+			}
+			if (parent == "" || depth > 0) && value.Name.Local == name {
+				var text string
+				if err := decoder.DecodeElement(&text, &value); err != nil {
+					return "", ErrInvalidResponse
+				}
+				return strings.TrimSpace(text), nil
+			}
+		case xml.EndElement:
+			if value.Name.Local == parent && depth > 0 {
+				depth--
+			}
+		}
+	}
+}