nostrmarket/nostr/event.py
2024-11-06 11:50:21 +02:00

57 lines
1.7 KiB
Python

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] = None
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 = self.sig and 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)