generate-password can be an external program

contrib/generate_password.sh

@@ -0,0 +1,3 @@
+#!/bin/sh
+
+shuf -n4 /usr/share/dict/words | tr '\n' . | head -c -1

tresetter.py

@@ -4,7 +4,7 @@ import random
 import logging
 import json
 import uuid
-from subprocess import Popen, CalledProcessError
+from subprocess import Popen, CalledProcessError, check_output
 from typing import Optional
 
 import redis
@@ -21,11 +21,15 @@ class Settings(BaseSettings):
     app_name: str = "tResetter"
     validate_login_exe: str
     change_password_exe: str
+    generate_password: Optional[str]
     redis_host: str = "localhost"
     expire_time: int = 60 * 20
     root_path: Optional[str]
     root_prefix: str = "/tresetter"
 
+    class Config:
+        pass
+
     @property
     def redis_params(self):
         return {"host": self.redis_host}
@@ -125,9 +129,15 @@ def validate(username, password):
     return p.returncode == 0
 
 
-def password_generate():
-    symbols = list(string.ascii_lowercase) + list(string.digits)
-    return "".join(random.choices(symbols, k=10))
+def password_generate() -> str:
+    if settings.generate_password:
+        s = check_output([settings.generate_password], encoding='utf8')
+        assert type(s) is str
+        return s.strip()
+
+    else:
+        symbols = list(string.ascii_lowercase) + list(string.digits)
+        return "".join(random.choices(symbols, k=10))
 
 
 def change_password(username: str, new_password: str) -> bool: