Telegram bot to compile js code in nodejs runtime. Sends standard output or error streams as result. The bot has a limit on the execution time of the script and protection from interferences with the file system and processes (through the fs and child_process libraries). It has user and group settings, such as setting a limit on the number of lines and characters in one message, the ability to temporarily turn off the bot in the group. It also has a built-in task queue with a limited number of scripts per user.
To implement the bot, the node-telegram-bot-api library was used. The bot instance is subscribed to the "text" event. The received message is sent to the onMessage handler method. Depending on the commands, different functions are executed from the commands.js file.
To store user and group settings, user_settings.csv and group_settings.csv files are used. When the bot starts, these files are parsed and the settings are written to the Map dictionaries (collections.js). When editing settings, the Map changes, and before shutting down the bot, use the /update command to overwrite the corresponding files.
To eliminate the possibility of user interaction with the file system and server-side processes, a separate process running from another user is used to execute the code:
sudo echo ${code} | su nodeuser -c 'timeout ${timeout}s node'
This user (nodeuser) has no rights to intervene in the server system.
/node - compiles the code entered after this command.
/start - gives instructions on how to use the bot.
/status - displays the current settings of the bot.
/maxchars - changes the maximum number of characters in a single output message (if in a group, available only to admins).
/maxlines - changes the maximum number of lines in one output message (if in a group, available only to admins).
/enable - enables bot in group.
/disable - disables the bot in the group.
/globaldisable - disables the bot for all chats.
/globalenable - enables a bot for all chats.
/timeout - sets the maximum runtime of the script.
/maxtasksperuser - sets the maximum number of scripts from one user in the queue.
/update - updates the group and user settings files.