feat: error handling + various fixes

.gitignore

@@ -2,3 +2,5 @@
 *.gz
 zerokno/zerokno.egg-info/PKG-INFO
 *.txt
+zerokno/__pycache__/zerokno.cpython-312.pyc
+test

README.md

@@ -1,6 +1,12 @@
 # ZeroKno
 
 ZeroKno is a simple, easy to use and lightweight zero-knowledge password storage method for Python.
+The keys are stored in plain text, while the passwords are stored as base58-encoded SHA-256 hashes.
+
+This makes it impossible for the application to know the password, while still being able to verify it. 
+If you want to use this in a production environment, please make sure to use a secure storage method for the keys (e.g. a secure database).
+
+Note that the passwords or values are not encrypted, but hashed. This means that the password cannot be retrieved from the hash, but the hash can be used to verify the password. Basically, you can't recover the password if you lose it.
 
 ## Installation
 
@@ -13,10 +19,10 @@ pip install zerokno
 ```python
 from zerokno import ZeroKno
 
-# Create a new ZeroKno instance
-zk = ZeroKno()
+# Create a new ZeroKno instance -- app_secret is a secret key for the application and storage is a directory to store the password hashes
+zk = ZeroKno(app_secret, storage) 
 
-# Add a new password
+# Add a new password -- please note that the password is stored as a hash, while the user id is stored as plain text
 zk.store("password", "userid")
 
 # Check password match
@@ -28,3 +34,8 @@ zk.validate("password", "userid1")
 # Error: Userid not found
 
 ```
+
+## Errors 
+
+- `Key not found` - This error is raised when the user id is not found in the storage
+- Any other error is raised when the storage file is not found or the storage file is corrupted or in any other way not accessible

test.py

@@ -0,0 +1,12 @@
+import zerokno.zerokno as zerokno # local import
+
+z = zerokno.ZeroKno(storage="./")
+
+pwd1 = input("Enter password: ")
+
+z.store(pwd1, "test")
+
+pwd2 = input("Enter password: ")
+
+print(z.validate(pwd2, "test"))
+# if this prints True, then the code is working as expected

zerokno/zerokno.py

@@ -3,18 +3,27 @@
 
 
 class ZeroKno:
-    def __init__(self, app_secret: str = None, storage: str = None):
+    def __init__(self, app_secret: str = "", storage: str = None):
         self.path = storage
         self.secret = app_secret
 
     @staticmethod
     def algo(password: str, secret: str) -> str:
-        return b58encode(sha256(password.encode()).digest())
+        try: return b58encode(sha256(password.encode()).digest()).decode()
+        except Exception as e: raise Exception(e)
 
     def store(self, password: str, uid: str) -> bool:
-        with open(self.path+uid, "w+") as f:
-            f.write(self.algo(password, self.secret))
+        try:
+            with open(self.path+uid, "w+") as f:
+                f.write(self.algo(password, self.secret))
+                return True
+        except Exception as e:
+            raise Exception(e)
+
 
     def validate(self, password: str, uid: str) -> bool:
-        with open(self.path+uid, "r") as f:
-            return self.algo(password, self.secret) == f.read()
+        try:
+            with open(self.path+uid, "r") as f:
+                return self.algo(password, self.secret) == f.read()
+        except FileNotFoundError:
+            raise Exception("Key not found")