§2023-07-07

$ pwd
/opt/xfs/home/alexlai/build/caddy-markdown-test/demo/munetakaJupyterHub

$ go mod init alexlai

$ go get -u github.com/russross/blackfriday/v2

• main.go

package main

import (
	"fmt"
	"io/ioutil"
	"net/http"
	"os"
	"path/filepath"

	"github.com/russross/blackfriday/v2"
)

func markdownHandler(w http.ResponseWriter, r *http.Request) {
	filePath := r.URL.Path[1:] // Remove leading slash

	// Check if the requested path is a directory
	if fileInfo, err := os.Stat(filePath); err == nil && fileInfo.IsDir() {
		filePath = filepath.Join(filePath, "index.md") // Append "index.md" for directory requests
	}

	// Check if the requested file exists
	if _, err := os.Stat(filePath); os.IsNotExist(err) {
		http.NotFound(w, r)
		return
	}

	// Read the markdown file
	markdownBytes, err := ioutil.ReadFile(filePath)
	if err != nil {
		http.Error(w, "Failed to read file", http.StatusInternalServerError)
		return
	}

	// Convert markdown to HTML using blackfriday
	htmlBytes := blackfriday.Run(markdownBytes)

	// Set the content type header to HTML
	w.Header().Set("Content-Type", "text/html")

	// Write the HTML response
	_, _ = w.Write(htmlBytes)
}

func main() {
	http.HandleFunc("/", markdownHandler)

	port := "8080"
	fmt.Printf("Starting server on port %s...\n", port)
	err := http.ListenAndServe(":"+port, nil)
	if err != nil {
		fmt.Printf("Server error: %s\n", err)
	}
}

• run

$ go run main.go
Starting server on port 8080...