feat: publish event on C_UD for stalls

nostr/event.py

@@ -0,0 +1,57 @@
+import hashlib
+import json
+from typing import List, Optional
+
+from pydantic import BaseModel
+from secp256k1 import PublicKey
+
+
+class NostrEvent(BaseModel):
+    id: str = ""
+    pubkey: str
+    created_at: int
+    kind: int
+    tags: List[List[str]] = []
+    content: str = ""
+    sig: Optional[str]
+
+    def serialize(self) -> List:
+        return [0, self.pubkey, self.created_at, self.kind, self.tags, self.content]
+
+    def serialize_json(self) -> str:
+        e = self.serialize()
+        return json.dumps(e, separators=(",", ":"), ensure_ascii=False)
+
+    @property
+    def event_id(self) -> str:
+        data = self.serialize_json()
+        id = hashlib.sha256(data.encode()).hexdigest()
+        return id
+
+    def check_signature(self):
+        event_id = self.event_id
+        if self.id != event_id:
+            raise ValueError(
+                f"Invalid event id. Expected: '{event_id}' got '{self.id}'"
+            )
+        try:
+            pub_key = PublicKey(bytes.fromhex("02" + self.pubkey), True)
+        except Exception:
+            raise ValueError(
+                f"Invalid public key: '{self.pubkey}' for event '{self.id}'"
+            )
+
+        valid_signature = pub_key.schnorr_verify(
+            bytes.fromhex(event_id), bytes.fromhex(self.sig), None, raw=True
+        )
+        if not valid_signature:
+            raise ValueError(f"Invalid signature: '{self.sig}' for event '{self.id}'")
+
+    def stringify(self) -> str:
+        return json.dumps(dict(self))
+
+    def tag_values(self, tag_name: str) -> List[str]:
+        return [t[1] for t in self.tags if t[0] == tag_name]
+
+    def has_tag_value(self, tag_name: str, tag_value: str) -> bool:
+        return tag_value in self.tag_values(tag_name)