Add function for markdown generation

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

Author: alexellis

markdown/go.mod

@@ -0,0 +1,5 @@
+module handler/function
+
+go 1.18
+
+require github.com/russross/blackfriday/v2 v2.1.0

markdown/go.sum

@@ -0,0 +1,2 @@
+github.com/russross/blackfriday/v2 v2.1.0 h1:JIOH55/0cWyOuilr9/qlrm0BSXldqnqwMsf35Ld67mk=
+github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=

markdown/handler.go

@@ -0,0 +1,32 @@
+package function
+
+import (
+	"io"
+	"net/http"
+
+	"github.com/russross/blackfriday/v2"
+)
+
+func Handle(w http.ResponseWriter, r *http.Request) {
+	var input []byte
+
+	if r.Body != nil {
+		defer r.Body.Close()
+
+		body, err := io.ReadAll(r.Body)
+		if err != nil {
+			http.Error(w, "Failed to read body", http.StatusInternalServerError)
+			return
+		}
+
+		input = body
+	}
+
+	// Convert Markdown to HTML
+	htmlContent := blackfriday.Run(input)
+
+	// Set response header for HTML
+	w.Header().Set("Content-Type", "text/html")
+	w.WriteHeader(http.StatusOK)
+	w.Write(htmlContent)
+}

stack.yml

@@ -96,8 +96,15 @@ functions:
     handler: ./external-ip
     image: ${SERVER:-ghcr.io}/${OWNER:-openfaas}/external-ip-fn:${TAG:-latest}
 
+  markdown:
+    lang: golang-middleware
+    handler: ./markdown
+    image: ${SERVER:-ghcr.io}/${OWNER:-openfaas}/markdown-fn:${TAG:-latest}
+
+
 configuration:
   templates:
     - name: golang-middleware
       source: https://github.com/openfaas/golang-http-template
 
+