Initial

Signed-off-by: Slendi <slendi@socopon.com>
2025-04-26 21:13:52 +03:00
commit b78866f8bd
5 changed files with 314 additions and 0 deletions
--- a/main.go
+++ b/main.go
@@ -0,0 +1,177 @@
+package main
+
+import (
+	"encoding/json"
+	"flag"
+	"fmt"
+	"io"
+	"math/rand"
+	"net/http"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+)
+
+var (
+	domain       string
+	listenAddr   string
+	staticDir    string
+	expireDur    time.Duration
+	expireOnView bool
+)
+
+type meta struct {
+	Expiry       time.Time `json:"expiry"`
+	ExpireOnView bool      `json:"expire_on_view"`
+}
+
+func randomID(n int) string {
+	letters := []rune("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789")
+	b := make([]rune, n)
+	for i := range b {
+		b[i] = letters[rand.Intn(len(letters))]
+	}
+	return string(b)
+}
+
+func indexHandler(w http.ResponseWriter, r *http.Request) {
+	w.Header().Add("Content-Type", "text/html")
+	fmt.Fprintf(w, `<html><body><pre>Welcome to slenpaste!
+Upload via curl:
+  curl -F 'file=@yourfile.txt' http://%s/
+
+Or via wget:
+  wget --method=POST --body-file=yourfile.txt http://%s/
+</pre>
+<form enctype="multipart/form-data" method="post">
+	<input type="file" name="file">
+
+	<fieldset style="margin-top: 1rem">
+		<legend>Expiry:</legend>
+		<label><input type="radio" name="expiry" value="0" checked> Never</label>
+		<label><input type="radio" name="expiry" value="5m"> 5 minutes</label>
+		<label><input type="radio" name="expiry" value="1h"> 1 hour</label>
+		<label><input type="radio" name="expiry" value="24h"> 1 day</label>
+		<label><input type="radio" name="expiry" value="view"> Expire on first view</label>
+	</fieldset><br/>
+
+	<input type="submit" value="Upload">
+</form>
+</body></html>`, domain, domain)
+}
+
+func uploadHandler(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		http.Error(w, "Only POST allowed", http.StatusMethodNotAllowed)
+		return
+	}
+
+	var reader io.Reader
+	if err := r.ParseMultipartForm(10 << 20); err == nil {
+		if file, _, err := r.FormFile("file"); err == nil {
+			defer file.Close()
+			reader = file
+		}
+	}
+	if reader == nil {
+		reader = r.Body
+		defer r.Body.Close()
+	}
+
+	expVal := r.FormValue("expiry")
+	var dur time.Duration
+	var onView bool
+	switch expVal {
+	case "view":
+		onView = true
+	case "0":
+		// no expiry
+	default:
+		dur, _ = time.ParseDuration(expVal)
+	}
+
+	id := randomID(6)
+	if err := os.MkdirAll(staticDir, 0755); err != nil {
+		http.Error(w, "Server error", http.StatusInternalServerError)
+		return
+	}
+	path := filepath.Join(staticDir, id)
+	out, err := os.Create(path)
+	if err != nil {
+		http.Error(w, "Save error", http.StatusInternalServerError)
+		return
+	}
+	defer out.Close()
+	if _, err := io.Copy(out, reader); err != nil {
+		http.Error(w, "Write error", http.StatusInternalServerError)
+		return
+	}
+
+	if dur > 0 || onView {
+		m := meta{ExpireOnView: onView}
+		if dur > 0 {
+			m.Expiry = time.Now().Add(dur)
+		}
+		metaBytes, _ := json.Marshal(m)
+		_ = os.WriteFile(path+".json", metaBytes, 0644)
+	}
+
+	fmt.Fprintf(w, "http://%s/%s\n", domain, id)
+}
+
+func viewHandler(w http.ResponseWriter, r *http.Request) {
+	id := strings.TrimPrefix(r.URL.Path, "/")
+	if id == "" {
+		indexHandler(w, r)
+		return
+	}
+	path := filepath.Join(staticDir, id)
+	metaPath := path + ".json"
+
+	// load and enforce metadata
+	if data, err := os.ReadFile(metaPath); err == nil {
+		var m meta
+		if err := json.Unmarshal(data, &m); err == nil {
+			if !m.Expiry.IsZero() && time.Now().After(m.Expiry) {
+				os.Remove(path)
+				os.Remove(metaPath)
+				http.NotFound(w, r)
+				return
+			}
+			if m.ExpireOnView {
+				defer os.Remove(path)
+				defer os.Remove(metaPath)
+			}
+		}
+	}
+
+	f, err := os.Open(path)
+	if err != nil {
+		http.NotFound(w, r)
+		return
+	}
+	defer f.Close()
+	w.Header().Set("Content-Type", "text/plain")
+	io.Copy(w, f)
+}
+
+func main() {
+	flag.StringVar(&domain, "domain", "localhost", "domain name for URLs")
+	flag.StringVar(&listenAddr, "listen", "0.0.0.0:8080", "listen address")
+	flag.StringVar(&staticDir, "static", "static", "directory to save pastes")
+	flag.DurationVar(&expireDur, "expire", 0, "time after which paste expires (e.g. 5m, 1h)")
+	flag.BoolVar(&expireOnView, "expire-on-view", false, "delete paste after it's viewed once")
+	flag.Parse()
+
+	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		if r.Method == http.MethodPost {
+			uploadHandler(w, r)
+		} else {
+			viewHandler(w, r)
+		}
+	})
+
+	fmt.Printf("slenpaste running at http://%s, storing in %s\n", listenAddr, staticDir)
+	http.ListenAndServe(listenAddr, nil)
+}