drivefs

Implements google drive to fs.FS

Path resolve

Google drive does not implement the file system in the unix filepath format, so we have to resolve this path, this can become costly for the API, we have to make a call for each separator (N+MS+1), so this will end up becoming slow to resolve (This path being /Frog/Google/files, it would be the same as 3 + 0.5ms + 1, total of 2.5ms), for this we have a cache of files in the folder that reduces this time but leaves it undone with the time

Example

package main

import (
	"context"
	"encoding/json"
	"flag"
	"fmt"
	"net"
	"net/http"
	"net/netip"
	"os"

	"golang.org/x/oauth2"
	"google.golang.org/api/drive/v3"
	"sirherobrine23.org/Sirherobrine23/drivefs"
)

var configPath string
var serverPort uint

func main() {
	flag.StringVar(&configPath, "config", "./config.json", "Config file path")
	flag.UintVar(&serverPort, "port", 8081, "server to listen")
	flag.Parse()

	var ggdrive *drivefs.Gdrive = new(drivefs.Gdrive)
	file, err := os.Open(configPath)
	if err != nil {
		panic(err)
	}
	defer file.Close()
	if err := json.NewDecoder(file).Decode(ggdrive); err != nil {
		panic(err)
	}

	if ggdrive.GoogleToken != nil {
		var err error
		if ggdrive, err = drivefs.New(ggdrive.GoogleOAuth, *ggdrive.GoogleToken); err != nil {
			panic(err)
		}
	} else {
		ln, err := net.Listen("tcp", ":0")
		if err != nil {
			panic(err)
		}
		P, _ := netip.ParseAddrPort(ln.Addr().String())
		ln.Close()
		ggdrive.GoogleOAuth.Redirects = []string{fmt.Sprintf("http://localhost:%d/callback", P.Port())}

		config := &oauth2.Config{ClientID: ggdrive.GoogleOAuth.Client, ClientSecret: ggdrive.GoogleOAuth.Secret, RedirectURL: ggdrive.GoogleOAuth.Redirects[0], Scopes: []string{drive.DriveScope, drive.DriveFileScope}, Endpoint: oauth2.Endpoint{AuthURL: ggdrive.GoogleOAuth.AuthURI, TokenURL: ggdrive.GoogleOAuth.TokenURI}}

		authURL := config.AuthCodeURL("state-token", oauth2.AccessTypeOffline)
		fmt.Printf("Go to the following link in your browser then type the authorization code: \n%v\n", authURL)

		var server *http.Server
		var code string
		mux := http.NewServeMux()
		mux.HandleFunc("/callback", func(w http.ResponseWriter, r *http.Request) {
			w.Header().Set("Content-Type", "text/plain")
			w.WriteHeader(200)
			w.Write([]byte("Doned\n"))
			code = r.URL.Query().Get("code")
			if code != "" {
				fmt.Printf("Code: %q\n", code)
				server.Close()
			}
		})

		server = &http.Server{Addr: P.String(), Handler: mux}
		if err := server.ListenAndServe(); err != nil && err != http.ErrServerClosed {
			panic(err)
		}

		ggdrive.GoogleToken, err = config.Exchange(context.TODO(), code)
		if err != nil {
			panic(fmt.Errorf("unable to retrieve token from web %v", err))
		}

		file.Close()
		if file, err = os.Create(configPath); err != nil {
			panic(err)
		}

		at := json.NewEncoder(file)
		at.SetIndent("", "  ")
		if err := at.Encode(ggdrive); err != nil {
			panic(err)
		}
	}

	fmt.Printf("server listening on :%d\n", serverPort)
	if err := http.ListenAndServe(fmt.Sprintf(":%d", serverPort), http.FileServerFS(ggdrive)); err != nil {
		fmt.Fprintln(os.Stderr, err.Error())
		os.Exit(1)
	}
}