feat: persist views (#120)

disagreement/client.py

@@ -2,8 +2,11 @@
 The main Client class for interacting with the Discord API.
 """
 
-import asyncio
-import signal
+import asyncio
+import signal
+import json
+import os
+import importlib
 from typing import (
     Optional,
     Callable,
@@ -16,7 +19,9 @@ from typing import (
     Dict,
     cast,
 )
-from types import ModuleType
+from types import ModuleType
+
+PERSISTENT_VIEWS_FILE = "persistent_views.json"
 
 from datetime import datetime, timedelta
 
@@ -77,7 +82,7 @@ def _update_list(lst: List[Any], item: Any) -> None:
     lst.append(item)
 
 
-class Client:
+class Client:
     """
     Represents a client connection that connects to Discord.
     This class is used to interact with the Discord WebSocket and API.
@@ -193,7 +198,10 @@ class Client:
         self._views: Dict[Snowflake, "View"] = {}
         self._persistent_views: Dict[str, "View"] = {}
         self._voice_clients: Dict[Snowflake, VoiceClient] = {}
-        self._webhooks: Dict[Snowflake, "Webhook"] = {}
+        self._webhooks: Dict[Snowflake, "Webhook"] = {}
+
+        # Load persistent views stored on disk
+        self._load_persistent_views()
 
         # Default whether replies mention the user
         self.mention_replies: bool = mention_replies
@@ -210,13 +218,46 @@ class Client:
             self.loop.add_signal_handler(
                 signal.SIGTERM, lambda: self.loop.create_task(self.close())
             )
-        except NotImplementedError:
-            # add_signal_handler is not available on all platforms (e.g., Windows default event loop policy)
-            # Users on these platforms would need to handle shutdown differently.
-            print(
-                "Warning: Signal handlers for SIGINT/SIGTERM could not be added. "
-                "Graceful shutdown via signals might not work as expected on this platform."
-            )
+        except NotImplementedError:
+            # add_signal_handler is not available on all platforms (e.g., Windows default event loop policy)
+            # Users on these platforms would need to handle shutdown differently.
+            print(
+                "Warning: Signal handlers for SIGINT/SIGTERM could not be added. "
+                "Graceful shutdown via signals might not work as expected on this platform."
+            )
+
+    def _load_persistent_views(self) -> None:
+        """Load registered persistent views from disk."""
+        if not os.path.isfile(PERSISTENT_VIEWS_FILE):
+            return
+        try:
+            with open(PERSISTENT_VIEWS_FILE, "r") as fp:
+                mapping = json.load(fp)
+        except Exception as e:  # pragma: no cover - best effort load
+            print(f"Failed to load persistent views: {e}")
+            return
+
+        for custom_id, path in mapping.items():
+            try:
+                module_name, class_name = path.rsplit(".", 1)
+                module = importlib.import_module(module_name)
+                cls = getattr(module, class_name)
+                view = cls()
+                self._persistent_views[custom_id] = view
+            except Exception as e:  # pragma: no cover - best effort load
+                print(f"Failed to initialize persistent view {path}: {e}")
+
+    def _save_persistent_views(self) -> None:
+        """Persist registered views to disk."""
+        data = {}
+        for custom_id, view in self._persistent_views.items():
+            cls = view.__class__
+            data[custom_id] = f"{cls.__module__}.{cls.__name__}"
+        try:
+            with open(PERSISTENT_VIEWS_FILE, "w") as fp:
+                json.dump(data, fp)
+        except Exception as e:  # pragma: no cover - best effort save
+            print(f"Failed to save persistent views: {e}")
 
     async def _initialize_gateway(self):
         """Initializes the GatewayClient if it doesn't exist."""
@@ -1707,11 +1748,13 @@ class Client:
 
         for item in view.children:
             if item.custom_id:  # Ensure custom_id is not None
-                if item.custom_id in self._persistent_views:
-                    raise ValueError(
-                        f"A component with custom_id '{item.custom_id}' is already registered."
-                    )
-                self._persistent_views[item.custom_id] = view
+                if item.custom_id in self._persistent_views:
+                    raise ValueError(
+                        f"A component with custom_id '{item.custom_id}' is already registered."
+                    )
+                self._persistent_views[item.custom_id] = view
+
+        self._save_persistent_views()
 
     # --- Application Command Methods ---
     async def process_interaction(self, interaction: Interaction) -> None:

docs/using_components.md

@@ -157,6 +157,22 @@ container = Container(
 A container can itself contain layout and content components, letting you build complex messages.
 
 
+## Persistent Views
+
+Views with ``timeout=None`` are persistent. Their ``custom_id`` components are saved to ``persistent_views.json`` so they survive bot restarts.
+
+```python
+class MyView(View):
+    @button(label="Press", custom_id="press")
+    async def handle(self, view, inter):
+        await inter.respond("Pressed!")
+
+client.add_persistent_view(MyView())
+```
+
+When the client starts, it loads this file and registers each view again. Remove
+the file to clear stored views.
+
 ## Next Steps
 
 - [Slash Commands](slash_commands.md)