strfry-policies/rate-limit-policy.ts
2023-03-21 00:20:27 -05:00

60 lines
1.5 KiB
TypeScript
Executable File

#!/bin/sh
//bin/true; exec deno run -A "$0" "$@"
import { readLines } from 'https://deno.land/std@0.178.0/io/mod.ts';
import { Keydb } from 'https://deno.land/x/keydb@1.0.0/sqlite.ts';
const IP_WHITELIST = (Deno.env.get('IP_WHITELIST') || '').split(',');
const RATE_LIMIT_INTERVAL = Number(Deno.env.get('RATE_LIMIT_INTERVAL') || 60000);
const RATE_LIMIT_MAX = Number(Deno.env.get('RATE_LIMIT_MAX') || 10);
interface InputMessage {
type: 'new' | 'lookback';
event: Event;
receivedAt: number;
sourceType: 'IP4' | 'IP6' | 'Import' | 'Stream' | 'Sync';
sourceInfo: string;
}
interface OutputMessage {
id: string;
action: 'accept' | 'reject' | 'shadowReject';
msg: string;
}
interface Event {
id: string;
sig: string;
kind: number;
tags: string[][];
pubkey: string;
content: string;
created_at: number;
}
async function handleMessage(msg: InputMessage): Promise<OutputMessage> {
if ((msg.sourceType === 'IP4' || msg.sourceType === 'IP6') && !IP_WHITELIST.includes(msg.sourceInfo)) {
const db = new Keydb('sqlite:///tmp/strfry-rate-limit-policy.sqlite3');
const count = await db.get<number>(msg.sourceInfo) || 0;
await db.set(msg.sourceInfo, count + 1, RATE_LIMIT_INTERVAL);
if (count >= RATE_LIMIT_MAX) {
return {
id: msg.event.id,
action: 'reject',
msg: 'Rate-limited.',
};
}
}
return {
id: msg.event.id,
action: 'accept',
msg: '',
};
}
for await (const line of readLines(Deno.stdin)) {
console.log(JSON.stringify(await handleMessage(JSON.parse(line))));
}