add timestamps to management requests

.gitignore

@@ -1,2 +1,3 @@
 redis
+sus
 .env

Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.18
+FROM golang:1.16
 
 WORKDIR /go/src/app
 COPY . .

docker-compose.yml

@@ -6,7 +6,10 @@ services:
     ports: [ "8430:80" ]
     environment:
       - SECRET=${SECRET}
+      - MAX_AGE_MS=${MAX_AGE_MS}
+    restart: unless-stopped
   redis:
+    hostname: sus-redis
     image: redis:7
     volumes: [ "./redis:/data" ]
-    ports: [ "6379:6379" ]
+    restart: unless-stopped

main.go

@@ -25,7 +25,6 @@ import (
 	"net/http"
 	"os"
 	"strconv"
-	"strings"
 	"time"
 
 	"github.com/go-redis/redis/v8"
@@ -34,17 +33,19 @@ import (
 )
 
 var client = redis.NewClient(&redis.Options{
-	Addr:     "redis:6379",
+	Addr:     "sus-redis:6379",
 	Password: "",
 	DB:       0,
 })
 
 var SECRET string
 var INDEX_GET_REDIRECT = "http://alv.cx"
+var MAX_AGE_MS int64 = 500
 
 func main() {
 	r := mux.NewRouter()
 	r.HandleFunc("/{shortlink}", shortlinkHandler)
+	r.HandleFunc("/{shortlink}/", shortlinkHandler)
 	r.HandleFunc("/", indexHandler)
 
 	listenAddress := "0.0.0.0:80"
@@ -61,6 +62,14 @@ func main() {
 		INDEX_GET_REDIRECT = p
 	}
 
+	if p, ok := os.LookupEnv("MAX_AGE_MS"); ok {
+		if v, err := strconv.ParseInt(p, 10, 64); err != nil {
+			fmt.Printf("Unable to parse environment variable MAX_AGE_MS: %v\n", p)
+		} else {
+			MAX_AGE_MS = v
+		}
+	}
+
 	log.Fatal(http.ListenAndServe(listenAddress, r))
 }
 
@@ -75,27 +84,30 @@ func indexHandler(w http.ResponseWriter, r *http.Request) {
 
 	command := r.PostForm.Get("Command")
 	shortlink := r.PostForm.Get("Shortlink")
-	redirect := r.PostForm.Get("Redirect")
+	value := r.PostForm.Get("Value")
-	alt_redirect := r.PostForm.Get("AltRedirect")
+	req_timestamp := r.PostForm.Get("Timestamp")
-	alt_condition := r.PostForm.Get("AltCondition")
+	req_timestamp_int, err := strconv.ParseInt(req_timestamp, 10, 64)
-	fmt.Printf("command: %v, shortlink: %v, redirect: %v, alt_redirect: %v, alt_condition: %v\n",
+	if err != nil {
-		command,
+		w.WriteHeader(http.StatusBadRequest)
-		shortlink,
+		w.Write([]byte("Bad request"))
-		redirect,
+		return
-		alt_redirect,
+	}
-		alt_condition,
-	)
 
-	formstring := command + ":" + shortlink + ":" + redirect + ":" + alt_condition + ":" + alt_redirect
+	cur_timestamp := time.Now().UnixNano()
+	if req_timestamp_int+MAX_AGE_MS*1000*1000 < cur_timestamp {
+		w.WriteHeader(http.StatusBadRequest)
+		w.Write([]byte("Bad request"))
+		return
+	}
 
-	fmt.Println("formstring: " + formstring)
+	fmt.Printf("req_timestamp: %v, command: %v, shortlink: %v, value: %v\n", req_timestamp, command, shortlink, value)
 
 	signature := r.Header.Get("Signature")
 	calculatedSignature := fmt.Sprintf(
 		"SUS-SIGNATURE-%v",
 		getSha256HMACSignature(
 			[]byte(SECRET),
-			command+":"+shortlink+":"+redirect+":"+alt_condition+":"+alt_redirect,
+			req_timestamp+":"+command+":"+shortlink+":"+value,
 		),
 	)
 
@@ -113,21 +125,7 @@ func indexHandler(w http.ResponseWriter, r *http.Request) {
 		ctx := context.Background()
 		_, err := client.Get(ctx, shortlink).Result()
 		if err == redis.Nil {
-			err = client.Set(ctx, shortlink+":redirect", shortlink, 0).Err()
+			err = client.Set(ctx, shortlink, value, 0).Err()
-			if err != nil {
-				fmt.Println(err)
-				w.WriteHeader(500)
-				w.Write([]byte("500 Internal Server Error"))
-				return
-			}
-			err = client.Set(ctx, shortlink+":altcondition", alt_condition, 0).Err()
-			if err != nil {
-				fmt.Println(err)
-				w.WriteHeader(500)
-				w.Write([]byte("500 Internal Server Error"))
-				return
-			}
-			err = client.Set(ctx, shortlink+":altredirect", alt_redirect, 0).Err()
 
 			if err != nil {
 				fmt.Println(err)
@@ -155,16 +153,13 @@ func indexHandler(w http.ResponseWriter, r *http.Request) {
 	}
 
 	if command == "delete" {
+		if value != "confirm" {
+			w.WriteHeader(400)
+			w.Write([]byte("400 Bad Request"))
+		}
+
 		ctx := context.Background()
-		if err := client.Del(ctx, shortlink+":redirect").Err(); err != nil {
+		if err := client.Del(ctx, shortlink).Err(); err != nil {
-			w.WriteHeader(500)
-			w.Write([]byte("500 Internal Server Error"))
-		}
-		if err := client.Del(ctx, shortlink+":altredirect").Err(); err != nil {
-			w.WriteHeader(500)
-			w.Write([]byte("500 Internal Server Error"))
-		}
-		if err := client.Del(ctx, shortlink+":altcondition").Err(); err != nil {
 			w.WriteHeader(500)
 			w.Write([]byte("500 Internal Server Error"))
 		}
@@ -182,13 +177,13 @@ func indexHandler(w http.ResponseWriter, r *http.Request) {
 
 		resp := ""
 		for _, key := range keys {
-			shortlink, err = client.Get(ctx, key).Result()
+			value, err = client.Get(ctx, key).Result()
 			if err == redis.Nil {
 				w.WriteHeader(500)
 				w.Write([]byte("500 Internal Server Error"))
 				return
 			}
-			resp += key + ":" + shortlink + "\n"
+			resp += key + ":" + value + "\n"
 		}
 
 		w.WriteHeader(200)
@@ -201,9 +196,7 @@ func shortlinkHandler(w http.ResponseWriter, r *http.Request) {
 	fmt.Println("shortlinkHandler called")
 	shortlink := string(mux.Vars(r)["shortlink"])
 	ctx := context.Background()
-	client.Incr(ctx, shortlink + ":hits")
+	redirect, err := client.Get(ctx, shortlink).Result()
-
-	redirect, err := client.Get(ctx, shortlink+":redirect").Result()
 	fmt.Printf("shortlink: %v, redirect: %v\n", shortlink, redirect)
 	if err == redis.Nil {
 		w.WriteHeader(404)
@@ -211,67 +204,13 @@ func shortlinkHandler(w http.ResponseWriter, r *http.Request) {
 		return
 	} else if err != nil {
 		fmt.Println(err)
-		fmt.Println(0)
 		w.WriteHeader(500)
 		w.Write([]byte("500 Internal Server Error"))
 		return
 	}
 
-	altcondition, err := client.Get(ctx, shortlink+":altcondition").Result()
-	if err == redis.Nil {
 	http.Redirect(w, r, redirect, 302)
 	return
-	} else if err != nil {
-		fmt.Println(err)
-		fmt.Println(1)
-		w.WriteHeader(500)
-		w.Write([]byte("500 Internal Server Error"))
-		return
-	}
-
-	altredirect, err := client.Get(ctx, shortlink+":altredirect").Result()
-	if err == redis.Nil {
-		http.Redirect(w, r, redirect, 302)
-		return
-	} else if err != nil {
-		fmt.Println(err)
-		fmt.Println(2)
-		w.WriteHeader(500)
-		w.Write([]byte("500 Internal Server Error"))
-		return
-	}
-
-	altcondition_split := strings.Split(altcondition, ",")
-	ac_varname := altcondition_split[0]
-	ac_operator := altcondition_split[1]
-	ac_required_value, _ := strconv.Atoi(altcondition_split[2])
-
-	var ac_varval int
-
-	if ac_varname != "timestamp" {
-		ac_varvalstr, err := client.Get(ctx, shortlink+":"+ac_varname).Result()
-		if err == redis.Nil {
-			ac_varval = 0
-		} else if err != nil {
-			fmt.Println(err)
-			fmt.Println(3)
-			w.WriteHeader(500)
-			w.Write([]byte("500 Internal Server Error"))
-			return
-		} else {
-			ac_varval, _ = strconv.Atoi(ac_varvalstr)
-		}
-	} else {
-		ac_varval = int(time.Now().Unix())
-	}
-
-	if (ac_operator == "eq" && ac_varval == ac_required_value) ||
-		(ac_operator == "gt" && ac_varval > ac_required_value) ||
-		(ac_operator == "lt" && ac_varval < ac_required_value) {
-		http.Redirect(w, r, altredirect, 307)
-	} else {
-		http.Redirect(w, r, redirect, 307)
-	}
 }
 
 func getSha256HMACSignature(secret []byte, data string) string {

readme.md

@@ -7,21 +7,11 @@ sus URL shortener
 
 - creating a new shortlink at https://pls.cx/shortlink
 
-        susmng [-s pls.cx] create -l shortlink -r https://example.com
+        susmng [-s pls.cx] create -l shortlink -v https://example.com
-
-- creating a new shortlink at https://pls.cx/shortlink which redirects to https://example.com/a the first n times, https://example.com/b any other times
-
-        susmng [-s pls.cx] create -l shortlink -r https://example.com/a \
-                -c hits,gt,<n> -a https://example.com/b
-
-- creating a new shortlink at https://pls.cx/shortlink which redirects to https://example.com/before before unix timestamp n (seconds), https://example.com/after after that
-
-        susmng [-s pls.cx] create -l shortlink -r https://example.com/before \
-                -c timestamp,gt,<n> -a https://example.com/after
 
 - deleting the shortlink https://pls.cx/shortlink
 
-        susmng [-s pls.cx] delete -l shortlink
+        susmng [-s pls.cx] delete -l shortlink -v confirm
 
 - listing all shortlinks on the server pls.cx
 
@@ -49,6 +39,7 @@ flag is not provided.
 - `LISTEN_ADDRESS`---the address the server is listening on (default is `0.0.0.0:80`)
 - `INDEX_GET_REDIRECT`---the URL the user should be redirected to if they try to access `/` on the
    server (default is `http://alv.cx`)
+- `MAX_AGE_MS`---how old a request can be (in milliseconds) before the server will refuse to process it. (default is 500 milliseconds)
 
 ### setting up susmng
 

susmng.py

@@ -8,6 +8,7 @@ import pathlib
 import os
 import json
 import sys
+import time
 
 
 def get_args():
@@ -18,10 +19,8 @@ def get_args():
     parser.add_argument('command')
     parser.add_argument('-s', '--server', default="")
     parser.add_argument('-l', '--shortlink', default="")
-    parser.add_argument('-r', '--redirect', default="")
+    parser.add_argument('-v', '--value', default="")
-    parser.add_argument('-a', '--alt-redirect', default="")
+    parser.add_argument('-c', '--config', type=pathlib.Path, default=pathlib.Path(os.path.expanduser('~/.config/susmng/config.json')))
-    parser.add_argument('-c', '--alt-condition', default="")
-    parser.add_argument('--config', type=pathlib.Path, default=pathlib.Path(os.path.expanduser('~/.config/susmng/config.json')))
     parser.add_argument('-H', '--http', action='store_true')
     return parser.parse_args()
 
@@ -50,25 +49,37 @@ def main(args):
 
     secret = config['secrets'][server]
 
-    formstring = args.command+":"+args.shortlink+":"+args.redirect+":"+args.alt_condition+":"+args.alt_redirect
+    if args.command == "delete" and args.value != "confirm":
-    print(f"{formstring=}")
+        print("--value not set to 'confirm'... delete operation may fail")
+
+    # accoring to python documentation (https://docs.python.org/3/library/time.html#time.time)
+    # this function does not explicitly have to use unix time, and implementation is dependent
+    # platform.
+    # most platforms (windows, unix) will probably give unix time though.
+    #
+    # the server side (main.go file) does explicitly use unix time (time.Now().UnixNano()) to get
+    # this number, but hopefully there should be no issues on most platforms.
+    timestamp = str(time.time_ns())
 
-    r = requests.post(f"{'http' if args.http else 'https'}://{server}",
     data = {
         'Command': args.command,
         'Shortlink': args.shortlink,
-                'Redirect': args.redirect,
+        'Value': args.value,
-                'AltCondition': args.alt_condition,
+        'Timestamp': timestamp,
-                'AltRedirect': args.alt_redirect,
+        }
-                },
+
     headers = {
         'Signature': 'SUS-SIGNATURE-' + hmac.new(
             secret.encode("UTF-8"),
-                    formstring.encode("UTF-8"),
+            (timestamp + ":" + args.command + ":" + args.shortlink + ":" + args.value).encode("UTF-8"),
             hashlib.sha256
             ).hexdigest()
         }
-            )
+
+    print(f"{data=}")
+    print(f"{headers=}")
+
+    r = requests.post(f"{'http' if args.http else 'https'}://{server}", data=data, headers=headers)
     print(r, file=sys.stderr)
     print(r.content.decode().strip())
     return 0