Update main application and dependencies

- Update main.py and run_web.py for local development
- Update microdot session handling
- Update wifi utility

lib/microdot/session.py

@@ -1,4 +1,25 @@
-import jwt
+try:
+    import jwt
+    HAS_JWT = True
+except ImportError:
+    HAS_JWT = False
+    try:
+        import ubinascii
+    except ImportError:
+        import binascii as ubinascii
+    try:
+        import uhashlib as hashlib
+    except ImportError:
+        import hashlib
+    try:
+        import uhmac as hmac
+    except ImportError:
+        try:
+            import hmac
+        except ImportError:
+            hmac = None
+    import json
+
 from microdot.microdot import invoke_handler
 from microdot.helpers import wraps
 
@@ -125,16 +146,61 @@ class Session:
             return response
 
     def encode(self, payload, secret_key=None):
-        return jwt.encode(payload, secret_key or self.secret_key,
-                          algorithm='HS256')
+        """Encode session data using JWT if available, otherwise use simple HMAC."""
+        if HAS_JWT:
+            return jwt.encode(payload, secret_key or self.secret_key,
+                              algorithm='HS256')
+        else:
+            # Simple encoding for MicroPython: base64(json) + HMAC signature
+            key = (secret_key or self.secret_key).encode() if isinstance(secret_key or self.secret_key, str) else (secret_key or self.secret_key)
+            payload_json = json.dumps(payload)
+            payload_b64 = ubinascii.b2a_base64(payload_json.encode()).decode().strip()
+            
+            # Create HMAC signature
+            if hmac:
+                # Use hmac module if available
+                h = hmac.new(key, payload_json.encode(), hashlib.sha256)
+            else:
+                # Fallback: simple SHA256(key + message)
+                h = hashlib.sha256(key + payload_json.encode())
+            signature = ubinascii.b2a_base64(h.digest()).decode().strip()
+            
+            return f"{payload_b64}.{signature}"
 
     def decode(self, session, secret_key=None):
-        try:
-            payload = jwt.decode(session, secret_key or self.secret_key,
-                                 algorithms=['HS256'])
-        except jwt.exceptions.PyJWTError:  # pragma: no cover
-            return {}
-        return payload
+        """Decode session data using JWT if available, otherwise use simple HMAC."""
+        if HAS_JWT:
+            try:
+                payload = jwt.decode(session, secret_key or self.secret_key,
+                                     algorithms=['HS256'])
+            except jwt.exceptions.PyJWTError:  # pragma: no cover
+                return {}
+            return payload
+        else:
+            try:
+                # Simple decoding for MicroPython
+                if '.' not in session:
+                    return {}
+                
+                payload_b64, signature = session.rsplit('.', 1)
+                payload_json = ubinascii.a2b_base64(payload_b64).decode()
+                
+                # Verify HMAC signature
+                key = (secret_key or self.secret_key).encode() if isinstance(secret_key or self.secret_key, str) else (secret_key or self.secret_key)
+                if hmac:
+                    # Use hmac module if available
+                    h = hmac.new(key, payload_json.encode(), hashlib.sha256)
+                else:
+                    # Fallback: simple SHA256(key + message)
+                    h = hashlib.sha256(key + payload_json.encode())
+                expected_signature = ubinascii.b2a_base64(h.digest()).decode().strip()
+                
+                if signature != expected_signature:
+                    return {}
+                
+                return json.loads(payload_json)
+            except Exception:
+                return {}
 
 
 def with_session(f):