implement basic protocol in nip-01

nostr/event.py

@@ -0,0 +1,54 @@
+import time
+import json
+from enum import IntEnum
+from secp256k1 import PrivateKey, PublicKey
+from hashlib import sha256
+
+class EventKind(IntEnum):
+    SET_METADATA = 0
+    TEXT_NOTE = 1
+    RECOMMEND_RELAY = 2
+
+class Event():
+    def __init__(
+            self, 
+            public_key: str, 
+            content: str, 
+            created_at: int=int(time.time()), 
+            kind: int=EventKind.TEXT_NOTE, 
+            tags: "list[list[str]]"=[], 
+            id: int=None, 
+            signature: str=None) -> None:
+        self.id = id if id != None else sha256(Event.serialize(public_key, created_at, kind, tags, content)).hexdigest()
+        self.public_key = public_key
+        self.content = content
+        self.created_at = created_at
+        self.kind = kind
+        self.tags = tags
+        self.signature = signature
+
+    @staticmethod
+    def serialize(public_key: str, created_at: int, kind: int, tags: "list[list[str]]", content: str) -> bytes:
+        data = [0, public_key, created_at, kind, tags, content]
+        data_str = json.dumps(data, separators=(',', ':'))
+        return data_str.encode()
+
+    def sign(self, sk: str) -> None:
+        private_key = PrivateKey(bytes.fromhex(sk))
+        sig = private_key.schnorr_sign(bytes.fromhex(self.id), None, raw=True)
+        self.signature = sig.hex()
+
+    def verify(self) -> bool:
+        pub_key = PublicKey(bytes.fromhex("02" + self.public_key), True) # add 02 for schnorr (bip340)
+        return pub_key.schnorr_verify(bytes.fromhex(self.id), bytes.fromhex(self.signature), None, raw=True)
+
+    def to_dict(self) -> dict:
+        return {
+            "id": self.id,
+            "pubkey": self.public_key,
+            "created_at": self.created_at,
+            "kind": self.kind,
+            "tags": self.tags,
+            "content": self.content,
+            "sig": self.signature
+        }