2023-08-13 16:48:04 +03:00

339 lines
14 KiB
TypeScript

import { type MiddlewareFn } from "../composer.js";
import { type Context } from "../context.js";
type MaybePromise<T> = Promise<T> | T;
/**
* A session flavor is a context flavor that holds session data under
* `ctx.session`.
*
* Session middleware will load the session data of a specific chat from your
* storage solution, and make it available to you on the context object. Check
* out the
* [documentation](https://doc.deno.land/https://deno.land/x/grammy/mod.ts/~/session)
* on session middleware to know more, and read the section about sessions on
* the [website](https://grammy.dev/plugins/session.html).
*/
export interface SessionFlavor<S> {
/**
* Session data on the context object.
*
* **WARNING:** You have to make sure that your session data is not
* undefined by _providing an initial value to the session middleware_, or by
* making sure that `ctx.session` is assigned if it is empty! The type
* system does not include `| undefined` because this is really annoying to
* work with.
*
* Accessing `ctx.session` by reading or writing will throw if
* `getSessionKey(ctx) === undefined` for the respective context object
* `ctx`.
*/
get session(): S;
set session(session: S | null | undefined);
}
/**
* A lazy session flavor is a context flavor that holds a promise of some
* session data under `ctx.session`.
*
* Lazy session middleware will provide this promise lazily on the context
* object. Once you access `ctx.session`, the storage will be queried and the
* session data becomes available. If you access `ctx.session` again for the
* same context object, the cached value will be used. Check out the
* [documentation](https://doc.deno.land/https://deno.land/x/grammy/mod.ts/~/lazySession)
* on lazy session middleware to know more, and read the section about lazy
* sessions on the
* [website](https://grammy.dev/plugins/session.html#lazy-sessions).
*/
export interface LazySessionFlavor<S> {
/**
* Session data on the context object, potentially a promise.
*
* **WARNING:** You have to make sure that your session data is not
* undefined by _providing a default value to the session middleware_, or by
* making sure that `ctx.session` is assigned if it is empty! The type
* system does not include `| undefined` because this is really annoying to
* work with.
*
* Accessing `ctx.session` by reading or writing will throw iff
* `getSessionKey(ctx) === undefined` holds for the respective context
* object `ctx`.
*/
get session(): MaybePromise<S>;
set session(session: MaybePromise<S | null | undefined>);
}
/**
* A storage adapter is an abstraction that provides read, write, and delete
* access to a storage solution of any kind. Storage adapters are used to keep
* session middleware independent of your database provider, and they allow you
* to pass your own storage solution.
*/
export interface StorageAdapter<T> {
/**
* Reads a value for the given key from the storage. May return the value or
* undefined, or a promise of either.
*/
read: (key: string) => MaybePromise<T | undefined>;
/**
* Writes a value for the given key to the storage.
*/
write: (key: string, value: T) => MaybePromise<void>;
/**
* Deletes a value for the given key from the storage.
*/
delete: (key: string) => MaybePromise<void>;
/**
* Checks whether a key exists in the storage.
*/
has?: (key: string) => MaybePromise<boolean>;
/**
* Lists all keys.
*/
readAllKeys?: () => Iterable<string> | AsyncIterable<string>;
/**
* Lists all values.
*/
readAllValues?: () => Iterable<T> | AsyncIterable<T>;
/**
* Lists all keys with their values.
*/
readAllEntries?: () => Iterable<[key: string, value: T]> | AsyncIterable<[key: string, value: T]>;
}
/**
* Options for session middleware.
*/
export interface SessionOptions<S, C extends Context = Context> {
type?: "single";
/**
* **Recommended to use.**
*
* A function that produces an initial value for `ctx.session`. This
* function will be called every time the storage solution returns undefined
* for a given session key. Make sure to create a new value every time, such
* that different context objects do that accidentally share the same
* session data.
*/
initial?: () => S;
/**
* This option lets you generate your own session keys per context object.
* The session key determines how to map the different session objects to
* your chats and users. Check out the
* [documentation](https://grammy.dev/plugins/session.html#how-to-use-sessions)
* on the website about how to use session middleware to know how session
* keys are used.
*
* The default implementation will store sessions per chat, as determined by
* `ctx.chat?.id`.
*/
getSessionKey?: (ctx: Omit<C, "session">) => MaybePromise<string | undefined>;
/**
* A storage adapter to your storage solution. Provides read, write, and
* delete access to the session middleware.
*
* Consider using a [known storage
* adapter](https://grammy.dev/plugins/session.html#known-storage-adapters)
* instead of rolling your own implementation of this.
*
* The default implementation will store session in memory. The data will be
* lost whenever your bot restarts.
*/
storage?: StorageAdapter<S>;
}
/**
* Options for session middleware if multi sessions are used. Specify `"type":
* "multi"` in the options to use multi sessions.
*/
export type MultiSessionOptions<S, C extends Context> = S extends Record<string, any> ? {
type: "multi";
} & MultiSessionOptionsRecord<S, C> : never;
type MultiSessionOptionsRecord<S extends Record<string, unknown>, C extends Context> = {
[K in keyof S]: SessionOptions<S[K], C>;
};
/**
* Session middleware provides a persistent data storage for your bot. You can
* use it to let your bot remember any data you want, for example the messages
* it sent or received in the past. This is done by attaching _session data_ to
* every chat. The stored data is then provided on the context object under
* `ctx.session`.
*
* > **What is a session?** Simply put, the session of a chat is a little
* > persistent storage that is attached to it. As an example, your bot can send
* > a message to a chat and store the ID of that message in the corresponding
* > session. The next time your bot receives an update from that chat, the
* > session will still contain that ID.
* >
* > Session data can be stored in a database, in a file, or simply in memory.
* > grammY only supports memory sessions out of the box, but you can use
* > third-party session middleware to connect to other storage solutions. Note
* > that memory sessions will be lost when you stop your bot and the process
* > exits, so they are usually not useful in production.
*
* Whenever your bot receives an update, the first thing the session middleware
* will do is to load the correct session from your storage solution. This
* object is then provided on `ctx.session` while your other middleware is
* running. As soon as your bot is done handling the update, the middleware
* takes over again and writes back the session object to your storage. This
* allows you to modify the session object arbitrarily in your middleware, and
* to stop worrying about the database.
*
* ```ts
* bot.use(session())
*
* bot.on('message', ctx => {
* // The session object is persisted across updates!
* const session = ctx.session
* })
* ```
*
* It is recommended to make use of the `initial` option in the configuration
* object, which correctly initializes session objects for new chats.
*
* You can delete the session data by setting `ctx.session` to `null` or
* `undefined`.
*
* Check out the [documentation](https://grammy.dev/plugins/session.html) on the
* website to know more about how sessions work in grammY.
*
* @param options Optional configuration to pass to the session middleware
*/
export declare function session<S, C extends Context>(options?: SessionOptions<S, C> | MultiSessionOptions<S, C>): MiddlewareFn<C & SessionFlavor<S>>;
/**
* > This is an advanced function of grammY.
*
* Generally speaking, lazy sessions work just like normal sessions—just they
* are loaded on demand. Except for a few `async`s and `await`s here and there,
* their usage looks 100 % identical.
*
* Instead of directly querying the storage every time an update arrives, lazy
* sessions quickly do this _once you access_ `ctx.session`. This can
* significantly reduce the database traffic (especially when your bot is added
* to group chats), because it skips a read and a wrote operation for all
* updates that the bot does not react to.
*
* ```ts
* // The options are identical
* bot.use(lazySession({ storage: ... }))
*
* bot.on('message', async ctx => {
* // The session object is persisted across updates!
* const session = await ctx.session
* // ^
* // |
* // This plain property access (no function call) will trigger the database query!
* })
* ```
*
* Check out the
* [documentation](https://grammy.dev/plugins/session.html#lazy-sessions) on the
* website to know more about how lazy sessions work in grammY.
*
* @param options Optional configuration to pass to the session middleware
*/
export declare function lazySession<S, C extends Context>(options?: SessionOptions<S, C>): MiddlewareFn<C & LazySessionFlavor<S>>;
/**
* When enhancing a storage adapter, it needs to be able to store additional
* information. It does this by wrapping the actual data inside an object, and
* adding more properties to this wrapper.
*
* This interface defines the additional properties that need to be stored by a
* storage adapter that supports enhanced sessions.
*/
export interface Enhance<T> {
/** Version */
v?: number;
/** Data */
__d: T;
/** Expiry date */
e?: number;
}
/** Options for enhanced sessions */
export interface MigrationOptions<T> {
/** The original storage adapter that will be enhanced */
storage: StorageAdapter<Enhance<T>>;
/**
* A set of session migrations, defined as an object mapping from version
* numbers to migration functions that transform data to the respective
* version.
*/
migrations?: Migrations;
/**
* Number of milliseconds after the last write operation until the session
* data expires.
*/
millisecondsToLive?: number;
}
/**
* A mapping from version numbers to session migration functions. Each entry in
* this object has a version number as a key, and a function as a value.
*
* For a key `n`, the respective value should be a function that takes the
* previous session data and migrates it to conform with the data that is used
* by version `n`. The previous session data is defined by the next key less
* than `n`, such as `n-1`. Versions don't have to be integers, nor do all
* versions have to be adjacent. For example, you can use `[1, 1.5, 4]` as
* versions. If `n` is the lowest value in the set of keys, the function stored
* for `n` can be used to migrate session data that was stored before migrations
* were used.
*/
export interface Migrations {
[version: number]: (old: any) => any;
}
/**
* You can use this function to transform an existing storage adapter, and add
* more features to it. Currently, you can add session migrations and expiry
* dates.
*
* You can use this function like so:
* ```ts
* const storage = ... // define your storage adapter
* const enhanced = enhanceStorage({ storage, millisecondsToLive: 500 })
* bot.use(session({ storage: enhanced }))
* ```
*
* @param options Session enhancing options
* @returns The enhanced storage adapter
*/
export declare function enhanceStorage<T>(options: MigrationOptions<T>): StorageAdapter<T>;
/**
* The memory session storage is a built-in storage adapter that saves your
* session data in RAM using a regular JavaScript `Map` object. If you use this
* storage adapter, all sessions will be lost when your process terminates or
* restarts. Hence, you should only use it for short-lived data that is not
* important to persist.
*
* This class is used as default if you do not provide a storage adapter, e.g.
* to your database.
*
* This storage adapter features expiring sessions. When instantiating this class
* yourself, you can pass a time to live in milliseconds that will be used for
* each session object. If a session for a user expired, the session data will
* be discarded on its first read, and a fresh session object as returned by the
* `initial` option (or undefined) will be put into place.
*/
export declare class MemorySessionStorage<S> implements StorageAdapter<S> {
private readonly timeToLive?;
/**
* Internally used `Map` instance that stores the session data
*/
protected readonly storage: Map<string, {
session: S;
expires?: number | undefined;
}>;
/**
* Constructs a new memory session storage with the given time to live. Note
* that this storage adapter will not store your data permanently.
*
* @param timeToLive TTL in milliseconds, default is `Infinity`
*/
constructor(timeToLive?: number | undefined);
read(key: string): S | undefined;
/**
* @deprecated Use {@link readAllValues} instead
*/
readAll(): S[];
readAllKeys(): string[];
readAllValues(): S[];
readAllEntries(): [string, S][];
has(key: string): boolean;
write(key: string, value: S): void;
delete(key: string): void;
}
export {};