x/grammy@v1.6.2/composer.ts

The Telegram Bot Framework.
GitHub Stars
568
Go to Latest
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700701702703704705706707708709710711712713714715716717718719720721722723724725726727728729730731732733734735736737738739740741742743744745746747748749750751752753754755756757758759760761762763764765766767768769770771772773774775776777778779780781782783784785786787788789790791792793794795796797798799800801802803804805806807808809810811812813814815816817818819820821822823824825826827828829830831832833834835836837838839840841842843844845846847848849850851852853854855856
import { Context } from "./context.ts";import { Filter, FilterQuery, matchFilter } from "./filter.ts";
type MaybePromise<T> = T | Promise<T>;type MaybeArray<T> = T | T[];// deno-lint-ignore ban-typestype StringWithSuggestions<S extends string> = (string & {}) | S; // permits `string` but gives hints
// === Middleware types/** * A function of this type is passed as the second parameter to all middleware. * Invoke it to call the downstream middleware and pass on the control flow. * * In other words, if your middleware is done handling the context object, and * other middleware should take over, this function should be called and * `await`ed. * * Once the `Promise` returned by this function resolves, the downstream * middleware is done executing, hence returning the control. */export type NextFunction = () => Promise<void>;
/** * Middleware in the form of a function. */export type MiddlewareFn<C extends Context = Context> = ( ctx: C, next: NextFunction,) => MaybePromise<unknown>;/** * Middleware in the form of a container for a function. */export interface MiddlewareObj<C extends Context = Context> { /** * Returns the contained middleware. */ middleware: () => MiddlewareFn<C>;}/** * Middleware for grammY, either as a function or as a container for a function. * * Simply put, middleware is just a fancy term for a _listener_. You can * register middleware on a bot to listen for updates. Example: * * ```ts * bot.on('message', ctx => ctx.reply('I got your message!')) * // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * // ^ * // | * // This is middleware! * ``` * * Middleware receives one object that we call the _context object_. This is * another fancy term for a simple object that holds information about the * update you're processing. For instance, the context object gives you access * to the message that was sent to your bot (`ctx.message`), including the text * (or photo or whatever message the user has sent). The context object is * commonly named `ctx`. * * It also provides you with the `ctx.api` object that you also find on * `bot.api`. As a result, you can call `ctx.api.sendMessage` instead of * `bot.api.sendMessage`. This prevents you from having to pass around your * `bot` instance all over your code. * * Most importantly, the context object gives you a handful of really useful * shortcuts, such as a `reply` method (see above). This method is nothing else * than a wrapper around `ctx.api.sendMessage`—but with some arguments * pre-filled for you. As you can see above, you no longer have to specify a * `chat_id` or anything; the context object knows which chat it belongs to, so * when you call `reply`, the context will call `sendMessage` with the correct * `chat_id`, namely the one for the same chat that the incoming message * originates from. This makes it very convenient to reply to a message. * * Middleware is an extremely powerful concept and this short explanation only * scratched the surface of what is possible with grammY. If you want to know * more advanced things about middleware, check out the * [documentation](https://grammy.dev/guide/middleware.html) on the website. */export type Middleware<C extends Context = Context> = | MiddlewareFn<C> | MiddlewareObj<C>;
// === Middleware errors/** * This error is thrown when middleware throws. It simply wraps the original * error (accessible via the `error` property), but also provides access to the * respective context object that was processed while the error occurred. */export class BotError<C extends Context = Context> extends Error { constructor(public readonly error: unknown, public readonly ctx: C) { super(generateBotErrorMessage(error)); this.name = "BotError"; if (error instanceof Error) this.stack = error.stack; }}function generateBotErrorMessage(error: unknown) { let msg: string; if (error instanceof Error) { msg = `${error.name} in middleware: ${error.message}`; } else { const type = typeof error; msg = `Non-error value of type ${type} thrown in middleware`; switch (type) { case "bigint": case "boolean": case "number": case "symbol": msg += `: ${error}`; break; case "string": msg += `: ${String(error).substring(0, 50)}`; break; default: msg += "!"; break; } } return msg;}
// === Middleware base functionsfunction flatten<C extends Context>(mw: Middleware<C>): MiddlewareFn<C> { return typeof mw === "function" ? mw : (ctx, next) => mw.middleware()(ctx, next);}function concat<C extends Context>( first: MiddlewareFn<C>, andThen: MiddlewareFn<C>,): MiddlewareFn<C> { return async (ctx, next) => { let nextCalled = false; await first(ctx, async () => { if (nextCalled) throw new Error("`next` already called before!"); else nextCalled = true; await andThen(ctx, next); }); };}function pass<C extends Context>(_ctx: C, next: NextFunction) { return next();}
const leaf: NextFunction = () => Promise.resolve();/** * Runs some given middleware function with a given context object. * * @param middleware The middleware to run * @param ctx The context to use */export async function run<C extends Context>( middleware: MiddlewareFn<C>, ctx: C,) { await middleware(ctx, leaf);}
// === Composer/** * The composer is the heart of the middleware system in grammY. It is also the * superclass of `Bot`. Whenever you call `use` or `on` or some of the other * methods on your bot, you are in fact using the underlying composer instance * to register your middleware. * * If you're just getting started, you do not need to worry about what * middleware is, or about how to use a composer. * * On the other hand, if you want to dig deeper into how grammY implements * middleware, check out the * [documentation](https://grammy.dev/advanced/middleware.html) on the website. */export class Composer<C extends Context> implements MiddlewareObj<C> { private handler: MiddlewareFn<C>;
/** * Constructs a new composer based on the provided middleware. If no * middleware is given, the composer instance will simply make all context * objects pass through without touching them. * * @param middleware The middleware to compose */ constructor(...middleware: Array<Middleware<C>>) { this.handler = middleware.length === 0 ? pass : middleware.map(flatten).reduce(concat); }
middleware() { return this.handler; }
/** * Registers some middleware that receives all updates. It is installed by * concatenating it to the end of all previously installed middleware. * * Often, this method is used to install middleware that behaves like a * plugin, for example session middleware. * ```ts * bot.use(session()) * ``` * * This method returns a new instance of composer. The returned instance can * be further extended, and all changes will be regarded here. Confer the * [documentation](https://grammy.dev/advanced/middleware.html) on the * website if you want to know more about how the middleware system in * grammY works, especially when it comes to chaining the method calls * (`use( ... ).use( ... ).use( ... )`). * * @param middleware The middleware to register */ use(...middleware: Array<Middleware<C>>) { const composer = new Composer(...middleware); this.handler = concat(this.handler, flatten(composer)); return composer; }
/** * Registers some middleware that will only be executed for some specific * updates, namely those matching the provided filter query. Filter queries * are a concise way to specify which updates you are interested in. * * Here are some examples of valid filter queries: * ```ts * // All kinds of message updates * bot.on('message', ctx => { ... }) * * // Only text messages * bot.on('message:text', ctx => { ... }) * * // Only text messages with URL * bot.on('message:entities:url', ctx => { ... }) * * // Text messages and text channel posts * bot.on(':text', ctx => { ... }) * * // Messages with URL in text or caption (i.e. entities or caption entities) * bot.on('message::url', ctx => { ... }) * * // Messages or channel posts with URL in text or caption * bot.on('::url', ctx => { ... }) * ``` * * You can use autocomplete in VSCode to see all available filter queries. * Check out the * [documentation](https://grammy.dev/guide/filter-queries.html) on the * website to learn more about filter queries in grammY. * * It is possible to pass multiple filter queries in an array, i.e. * ```ts * // Matches all text messages and edited text messages that contain a URL * bot.on(['message:entities:url', 'edited_message:entities:url'], ctx => { ... }) * ``` * * Your middleware will be executed if _any of the provided filter queries_ * matches (logical OR). * * If you instead want to match _all of the provided filter queries_ * (logical AND), you can chain the `.on` calls: * ```ts * // Matches all messages and channel posts that both a) contain a URL and b) are forwards * bot.on('::url').on(':forward_date', ctx => { ... }) * ``` * * @param filter The filter query to use, may also be an array of queries * @param middleware The middleware to register behind the given filter */ on<Q extends FilterQuery>( filter: Q | Q[], ...middleware: Array<Middleware<Filter<C, Q>>> ): Composer<Filter<C, Q>> { return this.filter(matchFilter<C, Q>(filter), ...middleware); }
/** * Registers some middleware that will only be executed when the message * contains some text. Is it possible to pass a regular expression to match: * ```ts * // Match some text (exact match) * bot.hears('I love grammY', ctx => ctx.reply('And grammY loves you! <3')) * // Match a regular expression * bot.hears(/\/echo (.+)/, ctx => ctx.reply(ctx.match[1])) * ``` * Note how `ctx.match` will contain the result of the regular expression. * Here it is a `RegExpMatchArray` object, so `ctx.match[1]` refers to the * part of the regex that was matched by `(.+)`, i.e. the text that comes * after “/echo”. * * You can pass an array of triggers. Your middleware will be executed if at * least one of them matches. * * Both text and captions of the received messages will be scanned. For * example, when a photo is sent to the chat and its caption matches the * trigger, your middleware will be executed. * * If you only want to match text messages and not captions, you can do * this: * ```ts * // Only matches text messages (and channel posts) for the regex * bot.on(':text').hears(/\/echo (.+)/, ctx => { ... }) * ``` * * @param trigger The text to look for * @param middleware The middleware to register */ hears( trigger: MaybeArray<string | RegExp>, ...middleware: Array<Middleware<HearsContext<C>>> ): Composer<HearsContext<C>> { const trg = triggerFn(trigger); return this.on([":text", ":caption"]).filter( (ctx): ctx is HearsContext<C> => { const msg = ctx.message ?? ctx.channelPost; const txt = msg.text ?? msg.caption; return match(ctx, txt, trg); }, ...middleware, ); }
/** * Registers some middleware that will only be executed when a certain * command is found. * ```ts * // Reacts to /start commands * bot.command('start', ctx => { ... }) * // Reacts to /help commands * bot.command('help', ctx => { ... }) * ``` * * The rest of the message (excluding the command, and trimmed) is provided * via `ctx.match`. * * > **Did you know?** You can use deep linking * > (https://core.telegram.org/bots#deep-linking) to let users start your * > bot with a custom payload. As an example, send someone the link * > https://t.me/name-of-your-bot?start=custom-payload and register a start * > command handler on your bot with grammY. As soon as the user starts * > your bot, you will receive `custom-payload` in the `ctx.match` * > property! * > ```ts * > bot.command('start', ctx => { * > const payload = ctx.match // will be 'custom-payload' * > }) * > ``` * * Note that commands are not matched in captions or in the middle of the * text. * ```ts * bot.command('start', ctx => { ... }) * // ... does not match: * // A message saying: “some text /start some more text” * // A photo message with the caption “/start” * ``` * * By default, commands are detected in channel posts, too. This means that * `ctx.message` is potentially `undefined`, so you should use `ctx.msg` * instead to grab both messages and channel posts. Alternatively, if you * want to limit your bot to finding commands only in private and group * chats, you can use `bot.on('message').command('start', ctx => { ... })`, * or even store a message-only version of your bot in a variable like so: * ```ts * const m = bot.on('message') * * m.command('start', ctx => { ... }) * m.command('help', ctx => { ... }) * // etc * ``` * * If you need more freedom matching your commands, check out the * `command-filter` plugin. * * @param command The command to look for * @param middleware The middleware to register */ command<S extends string>( command: MaybeArray< StringWithSuggestions<S | "start" | "help" | "settings"> >, ...middleware: Array<Middleware<CommandContext<C>>> ): Composer<CommandContext<C>> { const atCommands = new Set<string>(); const noAtCommands = new Set<string>(); toArray(command).forEach((cmd) => { if (cmd.startsWith("/")) { throw new Error( `Do not include '/' when registering command handlers (use '${ cmd.substring(1) }' not '${cmd}')`, ); } const set = cmd.indexOf("@") === -1 ? noAtCommands : atCommands; set.add(cmd); }); return this.on(":entities:bot_command").filter( (ctx): ctx is CommandContext<C> => { const msg = ctx.message ?? ctx.channelPost; const txt = msg.text; return msg.entities.some((e) => { if (e.type !== "bot_command") return false; if (e.offset !== 0) return false; const cmd = txt.substring(1, e.length); if (noAtCommands.has(cmd) || atCommands.has(cmd)) { ctx.match = txt.substring(cmd.length + 1).trimStart(); return true; } const index = cmd.indexOf("@"); if (index === -1) return false; const atTarget = cmd.substring(index + 1); if (atTarget !== ctx.me.username) return false; const atCommand = cmd.substring(0, index); if (noAtCommands.has(atCommand)) { ctx.match = txt.substring(cmd.length + 1).trimStart(); return true; } return false; }); }, ...middleware, ); }
/** * Registers some middleware for callback queries, i.e. the updates that * Telegram delivers to your bot when a user clicks an inline button (that * is a button under a message). * * This method is essentially the same as calling * ```ts * bot.on('callback_query:data', ctx => { ... }) * ``` * but it also allows you match the query data agains a given text or * regular expression. * * ```ts * // Create an inline keyboard * const keyboard = new InlineKeyboard().text('Go!', 'button-payload') * // Send a message with the keyboard * await bot.api.sendMessage(chat_id, 'Press a button!', { * reply_markup: keyboard * }) * // Listen to users pressing buttons with that specific payload * bot.callbackQuery('button-payload', ctx => { ... }) * * // Listen to users pressing any button your bot ever sent * bot.on('callback_query:data', ctx => { ... }) * ``` * * Always remember to call `answerCallbackQuery`—even if you don't perform * any action: https://core.telegram.org/bots/api#answercallbackquery * ```ts * bot.on('callback_query:data', async ctx => { * await ctx.answerCallbackQuery() * }) * ``` * * You can pass an array of triggers. Your middleware will be executed if at * least one of them matches. * * @param trigger The string to look for in the payload * @param middleware The middleware to register */ callbackQuery( trigger: MaybeArray<string | RegExp>, ...middleware: Array<Middleware<Filter<C, "callback_query:data">>> ): Composer<Filter<C, "callback_query:data">> { const trg = triggerFn(trigger); return this.on("callback_query:data").filter( (ctx) => match(ctx, ctx.callbackQuery.data, trg), ...middleware, ); }
/** * Registers some middleware for game queries, i.e. the updates that * Telegram delivers to your bot when a user clicks an inline button for the * HTML5 games platform on Telegram. * * This method is essentially the same as calling * ```ts * bot.on('callback_query:game_short_name', ctx => { ... }) * ``` * but it also allows you match the query data agains a given text or * regular expression. * * You can pass an array of triggers. Your middleware will be executed if at * least one of them matches. * * @param trigger The string to look for in the payload * @param middleware The middleware to register */ gameQuery( trigger: MaybeArray<string | RegExp>, ...middleware: Array< Middleware<Filter<C, "callback_query:game_short_name">> > ): Composer<Filter<C, "callback_query:game_short_name">> { const trg = triggerFn(trigger); return this.on("callback_query:game_short_name").filter( (ctx) => match(ctx, ctx.callbackQuery.game_short_name, trg), ...middleware, ); }
/** * Registers middleware for inline queries. Telegram sends an inline query * to your bot whenever a user types “@your_bot_name ...” into a text field * in Telegram. You bot will then receive the entered search query and can * respond with a number of results (text, images, etc) that the user can * pick from to send a message _via_ your bot to the respective chat. Check * out https://core.telegram.org/bots/inline to read more about inline bots. * * > Note that you have to enable inline mode for you bot by contacting * > @BotFather first. * * ```ts * // Listen for users typing “@your_bot_name query” * bot.inlineQuery('query', async ctx => { * // Answer the inline query, confer https://core.telegram.org/bots/api#answerinlinequery * await ctx.answerInlineQuery( ... ) * }) * ``` * * @param trigger The inline query text to match * @param middleware The middleware to register */ inlineQuery( trigger: MaybeArray<string | RegExp>, ...middleware: Array<Middleware<Filter<C, "inline_query">>> ): Composer<Filter<C, "inline_query">> { const trg = triggerFn(trigger); return this.on("inline_query").filter( (ctx) => match(ctx, ctx.inlineQuery.query, trg), ...middleware, ); }
/** * > This is an advanced method of grammY. * * Registers middleware behind a custom filter function that operates on the * context object and decides whether or not to execute the middleware. In * other words, the middleware will only be executed if the given predicate * returns `true` for the given context object. Otherwise, it will be * skipped and the next middleware will be executed. * * This method has two signatures. The first one is straightforward, it is * the one described above. Note that the predicate may be asyncronous, i.e. * it can return a Promise of a boolean. * * Alternatively, you can pass a function that has a type predicate as * return type. This will allow you to narrow down the context object. The * installed middleware is then able to operate on this constrained context * object. * ```ts * // NORMAL USAGE * // Only process every second update * bot.filter(ctx => ctx.update.update_id % 2 === 0, ctx => { ... }) * * // TYPE PREDICATE USAGE * function predicate(ctx): ctx is Context & { message: undefined } { * return ctx.message === undefined * } * // Only process updates where `message` is `undefined` * bot.filter(predicate, ctx => { * const m = ctx.message // inferred as always undefined! * const m2 = ctx.update.message // also inferred as always undefined! * }) * ``` * * @param predicate The predicate to check * @param middleware The middleware to register */ filter<D extends C>( predicate: (ctx: C) => ctx is D, ...middleware: Array<Middleware<D>> ): Composer<D>; filter( predicate: (ctx: C) => MaybePromise<boolean>, ...middleware: Array<Middleware<C>> ): Composer<C>; filter( predicate: (ctx: C) => MaybePromise<boolean>, ...middleware: Array<Middleware<C>> ) { const composer = new Composer(...middleware); this.branch(predicate, composer, pass); return composer; }
/** * > This is an advanced method of grammY. * * Registers middleware behind a custom filter function that operates on the * context object and decides whether or not to execute the middleware. In * other words, the middleware will only be executed if the given predicate * returns `false` for the given context object. Otherwise, it will be * skipped and the next middleware will be executed. Note that the predicate * may be asyncronous, i.e. it can return a Promise of a boolean. * * This method is the same using `filter` (normal usage) with a negated * predicate. * * @param predicate The predicate to check * @param middleware The middleware to register */ drop( predicate: (ctx: C) => MaybePromise<boolean>, ...middleware: Array<Middleware<C>> ) { return this.filter( async (ctx: C) => !(await predicate(ctx)), ...middleware, ); }
/** * > This is an advanced method of grammY. * * Registers some middleware that runs concurrently to the executing * middleware stack. * ```ts * bot.use( ... ) // will run first * bot.fork( ... ) // will be started second, but run concurrently * bot.use( ... ) // will also be run second * ``` * In the first middleware, as soon as `next`'s Promise resolves, both forks * have completed. * * Both the fork and the downstream middleware are awaited with * `Promise.all`, so you will only be to catch up to one error (the one that * is thrown first). * * In opposite to the other middleware methods on composer, `fork` does not * return simply return the composer connected to the main middleware stack. * Instead, it returns the created composer _of the fork_ connected to the * middleware stack. This allows for the following pattern. * ```ts * // Middleware will be run concurrently! * bot.fork().on('message', ctx => { ... }) * ``` * * @param middleware The middleware to run concurrently */ fork(...middleware: Array<Middleware<C>>) { const composer = new Composer(...middleware); const fork = flatten(composer); this.use((ctx, next) => Promise.all([next(), run(fork, ctx)])); return composer; }
/** * > This is an advanced method of grammY. * * Executes some middleware that can be generated on the fly for each * context. Pass a factory function that creates some middleware (or a * middleware array even). The factory function will be called once per * context, and its result will be executed with the context object. * ```ts * // The middleware returned by `createMyMiddleware` will be used only once * bot.lazy(ctx => createMyMiddleware(ctx)) * ``` * * You may generate this middleware in an `async` fashion. * * You can decide to return an empty array (`[]`) if you don't want to run * any middleware for a given context object. This is equivalent to * returning an empty instance of `Composer`. * * @param middlewareFactory The factory function creating the middleware */ lazy( middlewareFactory: (ctx: C) => MaybePromise<MaybeArray<Middleware<C>>>, ): Composer<C> { return this.use(async (ctx, next) => { const middleware = await middlewareFactory(ctx); const arr = toArray(middleware); await flatten(new Composer(...arr))(ctx, next); }); }
/** * > This is an advanced method of grammY. * * _Not to be confused with the `router` plugin._ * * This method is an alternative to the `router` plugin. It allows you to * branch between different middleware per context object. You can pass two * things to it: * 1. A routing function * 2. Different middleware identified by key * * The routing function decides based on the context object which middleware * to run. Each middleware is identified by a key, so the routing function * simply returns the key of that middleware. * ```ts * // Define different route handlers * const routeHandlers = { * evenUpdates: (ctx: Context) => { ... } * oddUpdates: (ctx: Context) => { ... } * } * // Decide for a context object which one to pick * const router = (ctx: Context) => ctx.update.update_id % 2 === 0 * ? 'evenUpdates' * : 'oddUpdates' * // Route it! * bot.route(router, routeHandlers) * ``` * * Optionally, you can pass a third option that is used as fallback * middleware if your route function returns `undefined`, or if the key * returned by your router has no middleware associated with it. * * This method may need less setup than first instanciating a `Router`, but * for more complex setups, having a `Router` may be more readable. * * @param router The routing function to use * @param routeHandlers Handlers for every route * @param fallback Optional fallback middleware if no route matches */ route<R extends Record<string, Middleware<C>>>( router: (ctx: C) => MaybePromise<undefined | keyof R>, routeHandlers: R, fallback: Middleware<C> = pass, ): Composer<C> { return this.lazy(async (ctx) => { const route = await router(ctx); return (route === undefined || !routeHandlers[route] ? fallback : routeHandlers[route]) ?? []; }); }
/** * > This is an advanced method of grammY. * * Allows you to branch between two cases for a given context object. * * This method takes a predicate function that is tested once per context * object. If it returns `true`, the first supplied middleware is executed. * If it returns `false`, the second supplied middleware is executed. Note * that the predicate may be asyncronous, i.e. it can return a Promise of a * boolean. * * @param predicate The predicate to check * @param trueMiddleware The middleware for the `true` case * @param falseMiddleware The middleware for the `false` case */ branch( predicate: (ctx: C) => MaybePromise<boolean>, trueMiddleware: MaybeArray<Middleware<C>>, falseMiddleware: MaybeArray<Middleware<C>>, ) { return this.lazy(async (ctx) => (await predicate(ctx)) ? trueMiddleware : falseMiddleware ); }
/** * > This is an advanced function of grammY. * * Installs an error boundary that catches errors that happen only inside * the given middleware. This allows you to install custom error handlers * that protect some parts of your bot. Errors will not be able to bubble * out of this part of your middleware system, unless the supplied error * handler rethrows them, in which case the next surrounding error boundary * will catch the error. * * Example usage: * ```ts * function errHandler(err: BotError) { * console.error('Error boundary caught error!', err) * } * * const safe = * // All passed middleware will be protected by the error boundary. * bot.errorBoundary(errHandler, middleware0, middleware1, middleware2) * * // Those will also be protected! * safe.on('message', middleware3) * * // No error from `middleware4` will reach the `errHandler` from above, * // as errors are suppressed. * * // do nothing on error (suppress error), and run outside middleware * const suppress = (_err: BotError, next: NextFunction) => { return next() } * safe.errorBoundary(suppress).on('edited_message', middleware4) * ``` * * Check out the * [documentation](https://grammy.dev/guide/errors.html#error-boundaries) on * the website to learn more about error boundaries. * * @param errorHandler The error handler to use * @param middleware The middleware to protect */ errorBoundary( errorHandler: ( error: BotError<C>, next: NextFunction, ) => MaybePromise<unknown>, ...middleware: Array<Middleware<C>> ) { const composer = new Composer<C>(...middleware); const bound = flatten(composer); this.use(async (ctx, next) => { let nextCalled = false; const cont = () => ((nextCalled = true), Promise.resolve()); try { await bound(ctx, cont); } catch (err) { nextCalled = false; await errorHandler(new BotError<C>(err, ctx), cont); } if (nextCalled) await next(); }); return composer; }}
// === Util functions and typesfunction triggerFn(trigger: MaybeArray<string | RegExp>) { return toArray(trigger).map((t) => typeof t === "string" ? (txt: string) => (txt === t ? t : null) : (txt: string) => txt.match(t) );}
type HearsContext<C extends Context> = Filter< C & { match: string | RegExpMatchArray }, ":text" | ":caption">;type CommandContext<C extends Context> = Filter< C & { match: string }, ":entities:bot_command">;
function match<C extends Context>( ctx: C, content: string, triggers: Array<(content: string) => string | RegExpMatchArray | null>,): boolean { for (const t of triggers) { const res = t(content); if (res) { ctx.match = res; return true; } } return false;}
function toArray<E>(e: MaybeArray<E>): E[] { return Array.isArray(e) ? e : [e];}