Mono repo -> Master (#22553)

Combines the following repositories into one:

https://github.com/mattermost/mattermost-server
https://github.com/mattermost/mattermost-webapp
https://github.com/mattermost/focalboard
https://github.com/mattermost/mattermost-plugin-playbooks

server/channels/app/imaging/svg.go

@@ -0,0 +1,86 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package imaging
+
+import (
+	"encoding/xml"
+	"fmt"
+	"io"
+	"strings"
+
+	"github.com/pkg/errors"
+)
+
+// SVGInfo holds information for a SVG image.
+type SVGInfo struct {
+	Width  int
+	Height int
+}
+
+// ParseSVG returns information for the given SVG input data.
+func ParseSVG(svgReader io.Reader) (SVGInfo, error) {
+	svgInfo := SVGInfo{
+		Width:  0,
+		Height: 0,
+	}
+
+	decoder := xml.NewDecoder(svgReader)
+
+	for {
+		token, err := decoder.Token()
+		if err != nil {
+			return svgInfo, err
+		}
+		switch t := token.(type) {
+		case xml.StartElement:
+			for _, attr := range t.Attr {
+				if attr.Name.Local == "viewBox" {
+					values := strings.Fields(attr.Value)
+					if len(values) == 4 {
+						width := 0
+						_, widthErr := fmt.Sscan(values[2], &width)
+
+						height := 0
+						_, heightErr := fmt.Sscan(values[3], &height)
+
+						if widthErr != nil || heightErr != nil {
+							return svgInfo, err
+						}
+
+						svgInfo.Width = width
+						svgInfo.Height = height
+
+						return svgInfo, nil
+					}
+				}
+				if attr.Name.Local == "width" {
+					width := 0
+					_, err := fmt.Sscan(attr.Value, &width)
+
+					if err != nil {
+						return svgInfo, err
+					}
+
+					svgInfo.Width = width
+				}
+				if attr.Name.Local == "height" {
+					height := 0
+					_, err := fmt.Sscan(attr.Value, &height)
+
+					if err != nil {
+						return svgInfo, err
+					}
+
+					svgInfo.Height = height
+				}
+			}
+
+			if svgInfo.Width == 0 || svgInfo.Height == 0 {
+				return svgInfo, errors.New("unable to extract SVG dimensions")
+			}
+
+			return svgInfo, nil
+		}
+	}
+}