Added MarkDown rendering support

Author: lkarlslund

go.mod

@@ -124,6 +124,7 @@ require (
 	github.com/gabriel-vasile/mimetype v1.4.7 // indirect
 	github.com/goccy/go-json v0.10.4 // indirect
 	github.com/godbus/dbus/v5 v5.1.0 // indirect
+	github.com/gomarkdown/markdown v0.0.0-20241205020045-f7e15b2f3e62 // indirect
 	github.com/google/deck v0.0.0-20230104221208-105ad94aa8ae // indirect
 	github.com/google/pprof v0.0.0-20240227163752-401108e1b7e7 // indirect
 	github.com/hashicorp/errwrap v1.1.0 // indirect

go.sum

@@ -149,6 +149,8 @@ github.com/golang/protobuf v1.4.0-rc.2/go.mod h1:LlEzMj4AhA7rCAGe4KMBDvJI+AwstrU
 github.com/golang/protobuf v1.4.0-rc.4.0.20200313231945-b860323f09d0/go.mod h1:WU3c8KckQ9AFe+yFwt9sWVRKCVIyN9cPHBJSNnbL67w=
 github.com/golang/protobuf v1.4.0/go.mod h1:jodUvKwWbYaEsadDk5Fwe5c77LiNKVO9IDvqG2KuDX0=
 github.com/golang/protobuf v1.4.2/go.mod h1:oDoupMAO8OvCJWAcko0GGGIgR6R6ocIYbsSw735rRwI=
+github.com/gomarkdown/markdown v0.0.0-20241205020045-f7e15b2f3e62 h1:pbAFUZisjG4s6sxvRJvf2N7vhpCvx2Oxb3PmS6pDO1g=
+github.com/gomarkdown/markdown v0.0.0-20241205020045-f7e15b2f3e62/go.mod h1:JDGcbDT52eL4fju3sZ4TeHGsQwhG9nbDV21aMyhwPoA=
 github.com/google/aukera v0.0.0-20201117230544-d145c8357fea/go.mod h1:oXqTZORBzdwQ6L32YjJmaPajqIV/hoGEouwpFMf4cJE=
 github.com/google/cabbie v1.0.2/go.mod h1:6MmHaUrgfabehCHAIaxdrbmvHSxUVXj3Abs08FMABSo=
 github.com/google/cabbie v1.0.5 h1:j+JWBiMpzJCTkVLKrzsNBQLkRff55sjzXc0AQOTV2JU=

modules/frontend/webservice.go

@@ -17,6 +17,9 @@ import (
 	"time"
 
 	"github.com/gin-gonic/gin"
+	"github.com/gomarkdown/markdown"
+	"github.com/gomarkdown/markdown/html"
+	"github.com/gomarkdown/markdown/parser"
 	jsoniter "github.com/json-iterator/go"
 	"github.com/lkarlslund/adalanche/modules/engine"
 	"github.com/lkarlslund/adalanche/modules/ui"
@@ -280,7 +283,19 @@ func (ws *WebService) ServeTemplate(c *gin.Context, path string, data any) {
 }
 
 func serveMarkDown(r io.Reader, ctx *gin.Context) {
+	md, _ := io.ReadAll(r)
 
+	extensions := parser.CommonExtensions | parser.AutoHeadingIDs | parser.NoEmptyLineBeforeBlock
+	p := parser.NewWithExtensions(extensions)
+	doc := p.Parse(md)
+
+	// create HTML renderer with extensions
+	htmlFlags := html.CommonFlags | html.HrefTargetBlank
+	opts := html.RendererOptions{Flags: htmlFlags}
+	renderer := html.NewRenderer(opts)
+
+	ctx.Status(200)
+	ctx.Writer.Write(markdown.Render(doc, renderer))
 }
 
 func serveTemplate(r io.Reader, ctx *gin.Context, data any) {