grammY Throttler (Transformer)

Throttling transformer for grammY bot framework, written in Typescript and built with Bottleneck.

About

This throttler aims to limit and queue outgoing Telegram API calls to conform to the official Telegram API rate limits.

Configuration

The throttler accepts a single optional argument of the following form:

type ThrottlerOptions = {
  global?: Bottleneck.ConstructorOptions;     // For throttling all api calls
  group?: Bottleneck.ConstructorOptions;      // For throttling outgoing group messages
  out?: Bottleneck.ConstructorOptions;        // For throttling outgoing private messages
};

The full list of object properties available for Bottleneck.ConstructorOptions can be found at Bottleneck.

If no argument is passed, the throttler created will use the default configuration settings which should be appropriate for most use cases. The default configuration are as follows:

// Outgoing Global Throttler
const globalConfig = {
  reservoir: 30,                  // Number of new jobs that throttler will accept at start
  reservoirRefreshAmount: 30,     // Number of jobs that throttler will accept after refresh
  reservoirRefreshInterval: 1000, // Interval in milliseconds where reservoir will refresh
};

// Outgoing Group Throttler
const groupConfig = {
  maxConcurrent: 1,                // Only 1 job at a time
  minTime: 1000,                   // Wait this many milliseconds to be ready, after a job
  reservoir: 20,                   // Number of new jobs that throttler will accept at start
  reservoirRefreshAmount: 20,      // Number of jobs that throttler will accept after refresh
  reservoirRefreshInterval: 60000, // Interval in milliseconds where reservoir will refresh
};

// Outgoing Private Throttler
const outConfig = {
  maxConcurrent: 1,                // Only 1 job at a time
  minTime: 1000,                   // Wait this many milliseconds to be ready, after a job
};

Usage

import { Bot } from 'https://lib.deno.dev/x/grammy@1/mod.ts';
import { run } from 'https://lib.deno.dev/x/grammy_runner@1/mod.ts';
import { apiThrottler, bypassThrottler } from 'https://lib.deno.dev/x/grammy_transformer_throttler@1/mod.ts';

const botToken = Deno.env.get('BOT_TOKEN');
if (!botToken) {
  throw Error('BOT_TOKEN is required');
}
const bot = new Bot(botToken);

const throttler = apiThrottler();
bot.api.config.use(throttler);

// Experimental: Do not throttle update-initiated first response
bot.use(bypassThrottler);
bot.command('/example', ctx => ctx.reply('I am throttled'));

// If you are using throttler, you most likely want to use a runner to handle updates concurrently
run(bot);