Can get the ID of a user from its email address

src/helpers/AccountHelper.ts

@@ -175,6 +175,24 @@ export class AccountHelper {
 		}) > 0;
 	}
 
+	/**
+	 * Find user ID from its email address
+	 * 
+	 * @param email Email address
+	 * @returns The ID of the matching user / -1 if none found
+	 */
+	public static async FindIDFromEmail(email: string) : Promise<number> {
+		const result = await DatabaseHelper.QueryRow({
+			table: USER_TABLE,
+			where: {
+				mail: email,
+			},
+			fields: ["ID"]
+		});
+
+		return result == null ? -1 : result.ID;
+	}
+
 
 	/**
 	 * Check out whether a virtual directory is available or not