まあ resolve #2 かな

src/functions/gen-token.ts

@@ -0,0 +1,13 @@
+import rndstr from 'rndstr';
+import { UsedToken } from '../models/entities/usedToken';
+import { UsedTokens } from '../models';
+
+export const genToken = async (): Promise<string> => {
+	let used: UsedToken | undefined = undefined;
+	let token: string;
+	do {
+		token = rndstr(32);
+		used = await UsedTokens.findOne({ token });
+	} while (used !== undefined);
+	return token;
+};