Add an example for Stage and Scene with a custom context #1139
Description
Is your feature request related to a problem? Please describe.
I'm new to typescript and I've been trying to write a bot that has uses session with a custom session object and stages.
I haven't found any examples of Stages using a custom context type.
Describe the solution you'd like
A complete example with a bot with a custom type and stages using that custom type.
Additional context
This is the code I have
import { Telegraf, Context, Stage, BaseScene } from 'telegraf'
import LocalSession from 'telegraf-session-local'
interface Session {
bar: string
}
interface BotContext extends Context {
session: Session
}
const bot = new Telegraf<BotContext>('foo')
const session = new LocalSession<BotContext>()
bot.use(session.middleware())
const scene = new BaseScene('scene')
scene.command('back', ctx => ctx.scene.leave())
const stage = new Stage([scene], { ttl: 10 })
bot.use(stage.middleware())
bot.command('foo', ctx => ctx.scene.enter('scene'))
bot.launch()bot.use(stage.middleware()) shows the following
Argument of type 'MiddlewareFn<SceneContextMessageUpdate>' is not assignable to parameter of type 'Middleware<BotContext>'.
Type 'MiddlewareFn<SceneContextMessageUpdate>' is not assignable to type 'MiddlewareFn<BotContext>'.
Property 'scene' is missing in type 'BotContext' but required in type 'SceneContextMessageUpdate'.
and bot.command('foo', ctx => ctx.scene.enter('scene')) shows
Property 'scene' does not exist on type 'BotContext'.
I though that using BaseScene<BotContext> and Stage<BotContext> would make it work, but I get the following instead
For BaseScene<BotContext>
Type 'BotContext' does not satisfy the constraint 'SceneContextMessageUpdate'.
Property 'scene' is missing in type 'BotContext' but required in type 'SceneContextMessageUpdate'.
And for Stage<BotContext>
Type 'BotContext' does not satisfy the constraint 'SceneContextMessageUpdate'.
I did get to code that compiles by doing the following
import { Telegraf, Context, Stage, BaseScene } from 'telegraf'
import LocalSession from 'telegraf-session-local'
import { SceneContextMessageUpdate } from '../node_modules/telegraf/typings/stage.d'
interface Session {
foo: string
}
type BaseBotContext = Context & SceneContextMessageUpdate
interface BotContext extends BaseBotContext {
session: Session
}
const bot = new Telegraf<BotContext>('foo')
const session = new LocalSession<BotContext>()
bot.use(session.middleware())
const scene = new BaseScene<BotContext>('scene')
scene.command('back', ctx => ctx.scene.leave())
const stage = new Stage<BotContext>([scene], { ttl: 10 })
bot.use(stage.middleware())
bot.command('foo', ctx => ctx.scene.enter('scene'))
bot.launch()Is the type BaseBotContext = Context & SceneContextMessageUpdate the way to do this?