TiddlyWiki Saver Server (Simple)

server.go

// From a directory that contains your TiddlyWiki file (or download https://tiddlywiki.com/empty.html if you don't have one)
// `go run main.go`
// Navigate to the printed URL and open your wiki file
// Enjoy your changes getting saved !

package main

import (
	"fmt"
	"io"
	"log"
	"net/http"
	"os"
	"path/filepath"
)

func main() {
	var root string

	if len(os.Args) != 1 {
		root = os.Args[1]
	} else {
		root = "."
	}

	fmt.Println(root)

	fileServerHandler := http.FileServer(http.Dir(root))

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
		switch r.Method {
		case "GET":
			fileServerHandler.ServeHTTP(w, r)
		case "PUT":
			handlePut(w, r, root)
		case "OPTIONS":
			handleOptions(w, r)
		default:
			w.WriteHeader(200)
		}
	})

	server := &http.Server{
		Addr:    "127.0.0.1:8000",
		Handler: http.DefaultServeMux,
	}

	go func() {
		if err := server.ListenAndServe(); err != nil {
			fmt.Println(err)
		}
	}()

	fmt.Println("TiddlyWiki Backup Server is running at http://127.0.0.1:8000/")
	fmt.Println("Press Ctrl+C to shutdown...")
	select {}
}

func handlePut(w http.ResponseWriter, r *http.Request, root string) {
	filePath := filepath.Join(root, r.URL.Path)

	writeErr := func(err error) {
		log.Printf("error: %s", err)
		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
	}

	src, err := os.Open(filePath)
	if err != nil {
		http.Error(w, "Not Found", http.StatusNotFound)
		return
	}
	defer src.Close()

	body, err := io.ReadAll(r.Body)
	if err != nil {
		writeErr(err)
		return
	}

	if err := os.WriteFile(filePath, body, os.ModePerm); err != nil {
		writeErr(err)
		return
	}

	w.WriteHeader(http.StatusOK)
	fmt.Print(".")
}

func handleOptions(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Allow", "GET,HEAD,OPTIONS,PUT")
	// TiddlyWiki looks for a 'dav' header, and ignores any value
	w.Header().Set("dav", "anything")
}