add nostr

nostr/relay.py

@@ -0,0 +1,124 @@
+import json
+from threading import Lock
+from websocket import WebSocketApp
+from .event import Event
+from .filter import Filters
+from .message_pool import MessagePool
+from .message_type import RelayMessageType
+from .subscription import Subscription
+
+
+class RelayPolicy:
+    def __init__(self, should_read: bool = True, should_write: bool = True) -> None:
+        self.should_read = should_read
+        self.should_write = should_write
+
+    def to_json_object(self) -> dict[str, bool]:
+        return {"read": self.should_read, "write": self.should_write}
+
+
+class Relay:
+    def __init__(
+        self,
+        url: str,
+        policy: RelayPolicy,
+        message_pool: MessagePool,
+        subscriptions: dict[str, Subscription] = {},
+    ) -> None:
+        self.url = url
+        self.policy = policy
+        self.message_pool = message_pool
+        self.subscriptions = subscriptions
+        self.lock = Lock()
+        self.ws = WebSocketApp(
+            url,
+            on_open=self._on_open,
+            on_message=self._on_message,
+            on_error=self._on_error,
+            on_close=self._on_close,
+        )
+
+    def connect(self, ssl_options: dict = None):
+        self.ws.run_forever(sslopt=ssl_options)
+
+    def close(self):
+        self.ws.close()
+
+    def publish(self, message: str):
+        self.ws.send(message)
+
+    def add_subscription(self, id, filters: Filters):
+        with self.lock:
+            self.subscriptions[id] = Subscription(id, filters)
+
+    def close_subscription(self, id: str) -> None:
+        with self.lock:
+            self.subscriptions.pop(id)
+
+    def update_subscription(self, id: str, filters: Filters) -> None:
+        with self.lock:
+            subscription = self.subscriptions[id]
+            subscription.filters = filters
+
+    def to_json_object(self) -> dict:
+        return {
+            "url": self.url,
+            "policy": self.policy.to_json_object(),
+            "subscriptions": [
+                subscription.to_json_object()
+                for subscription in self.subscriptions.values()
+            ],
+        }
+
+    def _on_open(self, class_obj):
+        pass
+
+    def _on_close(self, class_obj, status_code, message):
+        pass
+
+    def _on_message(self, class_obj, message: str):
+        if self._is_valid_message(message):
+            self.message_pool.add_message(message, self.url)
+
+    def _on_error(self, class_obj, error):
+        # print(error)
+        pass
+
+    def _is_valid_message(self, message: str) -> bool:
+        message = message.strip("\n")
+        if not message or message[0] != "[" or message[-1] != "]":
+            return False
+
+        message_json = json.loads(message)
+        message_type = message_json[0]
+        if not RelayMessageType.is_valid(message_type):
+            return False
+        if message_type == RelayMessageType.EVENT:
+            if not len(message_json) == 3:
+                return False
+
+            subscription_id = message_json[1]
+            with self.lock:
+                if subscription_id not in self.subscriptions:
+                    return False
+
+            e = message_json[2]
+            event = Event(
+                e["pubkey"],
+                e["content"],
+                e["created_at"],
+                e["kind"],
+                e["tags"],
+                e["id"],
+                e["sig"],
+            )
+            if not event.verify():
+                return False
+
+            with self.lock:
+                subscription = self.subscriptions[subscription_id]
+
+            if not subscription.filters.match(event):
+                return False
+
+        return True