Render and sanitize chat messages server-side. (#237)

* Render and sanitize chat messages server-side. Closes #235

* Render content.md server-side and return it in the client config

* Remove showdown from web project

* Update api spec

* Move example user content file

utils/utils.go

@@ -1,12 +1,17 @@
 package utils
 
 import (
+	"bytes"
 	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
 
 	"github.com/mssola/user_agent"
+	"github.com/yuin/goldmark"
+	"github.com/yuin/goldmark/extension"
+	"github.com/yuin/goldmark/renderer/html"
+	"mvdan.cc/xurls"
 )
 
 //GetTemporaryPipePath gets the temporary path for the streampipe.flv file
@@ -65,3 +70,30 @@ func IsUserAgentABot(userAgent string) bool {
 	ua := user_agent.New(userAgent)
 	return ua.Bot()
 }
+
+func RenderSimpleMarkdown(raw string) string {
+	markdown := goldmark.New(
+		goldmark.WithRendererOptions(
+			html.WithUnsafe(),
+		),
+		goldmark.WithExtensions(
+			extension.NewLinkify(
+				extension.WithLinkifyAllowedProtocols([][]byte{
+					[]byte("http:"),
+					[]byte("https:"),
+				}),
+				extension.WithLinkifyURLRegexp(
+					xurls.Strict,
+				),
+			),
+		),
+	)
+
+	trimmed := strings.TrimSpace(raw)
+	var buf bytes.Buffer
+	if err := markdown.Convert([]byte(trimmed), &buf); err != nil {
+		panic(err)
+	}
+
+	return buf.String()
+}