tachybase_todo/docs/en-US/api/database/index.md
2022-12-30 23:19:46 +08:00

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# Database
## Overview
Database is the database interaction tool provided by NocoBase, it provides very convenient database interaction features for no-code and low-code applications. The supported databases are:
* SQLite 3.8.8+
* MySQL 8.0.17+
* PostgreSQL 10.0+
### Connect to Database
In `Database` constructor, database connection can be configured by passing the `options` parameter.
```javascript
const { Database } = require('@nocobase/database');
// SQLite database configuration parameters
const database = new Database({
dialect: 'sqlite',
storage: 'path/to/database.sqlite'
})
// MySQL \ PostgreSQL database configuration parameters
const database = new Database({
dialect: /* 'postgres' or 'mysql' */,
database: 'database',
username: 'username',
password: 'password',
host: 'localhost',
port: 'port'
})
```
Refer to [Constructor](#constructor) for detailed configurations.
### Define Data Structure
`Database` defines database structure through `Collection`, one `Collection` object represents one table in the database.
```javascript
// Define Collection
const UserCollection = database.collection({
name: 'users',
fields: [
{
name: 'name',
type: 'string',
},
{
name: 'age',
type: 'integer',
},
],
});
```
After the database structure is defined, use `sync()` method to synchronize the database structure.
```javascript
await database.sync();
```
Refer to [Collection](/api/database/collection.md) for detailed usage of `Collection`.
### CRUD Data
`Database` operates data through `Repository`.
```javascript
const UserRepository = UserCollection.repository();
// Create
await UserRepository.create({
name: 'Mark',
age: 18,
});
// Query
const user = await UserRepository.findOne({
filter: {
name: 'Mark',
},
});
// Update
await UserRepository.update({
values: {
age: 20,
},
});
// Delete
await UserRepository.destroy(user.id);
```
Refer to [Repository](/api/database/repository.md) for details of data CRUD.
## Constructor
**Signature**
* `constructor(options: DatabaseOptions)`
Create a database instance.
**Parameter**
| Name | Type | Default | Description |
| --- | --- | --- | --- |
| `options.host` | `string` | `'localhost'` | Database host |
| `options.port` | `number` | - | Database service port, there is a default port depending on the database used |
| `options.username` | `string` | - | Database username |
| `options.password` | `string` | - | Database password|
| `options.database` | `string` | - | Database name |
| `options.dialect` | `string` | `'mysql'` | Database type |
| `options.storage?` | `string` | `':memory:'` | Storage mode for SQLite |
| `options.logging?` | `boolean` | `false` | Whether to enable logging |
| `options.define?` | `Object` | `{}` | Default table definition parameters |
| `options.tablePrefix?` | `string` | `''` | NocoBase extension, table prefix |
| `options.migrator?` | `UmzugOptions` | `{}` | NocoBase extension, parameters for migrator, refer to [Umzug](https://github.com/sequelize/umzug/blob/main/src/types.ts#L15) for the implementation |
## Migration Methods
### `addMigration()`
Add single migration file.
**Signature**
* `addMigration(options: MigrationItem)`
**Parameter**
| Name | Type | Default | Description |
| --- | --- | --- | --- |
| `options.name` | `string` | - | Name of the migration file |
| `options.context?` | `string` | - | Context of the migration file |
| `options.migration?` | `typeof Migration` | - | Custom type of the migration file |
| `options.up` | `Function` | - | `up` method of the migration file |
| `options.down` | `Function` | - | `down` method of the migration file |
**Example**
```ts
db.addMigration({
name: '20220916120411-test-1',
async up() {
const queryInterface = this.context.db.sequelize.getQueryInterface();
await queryInterface.query(/* your migration sqls */);
}
});
```
### `addMigrations()`
Add the migration files in the specified directory.
**Signature**
* `addMigrations(options: AddMigrationsOptions): void`
**Parameter**
| Name | Type | Default | Description |
| --- | --- | --- | --- |
| `options.directory` | `string` | `''` | Directory where the migration files are located |
| `options.extensions` | `string[]` | `['js', 'ts']` | File extensions |
| `options.namespace?` | `string` | `''` | Namespace |
| `options.context?` | `Object` | `{ db }` | Context of the migration files |
**Example**
```ts
db.addMigrations({
directory: path.resolve(__dirname, './migrations'),
namespace: 'test'
});
```
## Tool Methods
### `inDialect()`
Check whether the current database type is the specified type.
**Signature**
* `inDialect(dialect: string[]): boolean`
**Parameter**
| Name | Type | Default | Description |
| --- | --- | --- | --- |
| `dialect` | `string[]` | - | Database type, options are `mysql`, `postgres` and `sqlite` |
### `getTablePrefix()`
Get the table name prefix in the configuration.
**Signature**
* `getTablePrefix(): string`
## Data Table Configuration
### `collection()`
Define a data table. This is similar to the `define` method of Sequelize, which only creates table structure in memory. Call the `sync` method if it is needed to be persisted to the database.
**Signature**
* `collection(options: CollectionOptions): Collection`
**Parameter**
All configuration parameters of `options` is consistent with the constructor of the `Collection` class, refer to [Collection](/api/server/database/collection#Constructor).
**Event**
* `'beforeDefineCollection'`: Trigger before defining the table.
* `'afterDefineCollection'`: Trigger after defining the table.
**Example**
```ts
db.collection({
name: 'books',
fields: [
{
type: 'string',
name: 'title',
},
{
type: 'float',
name: 'price',
}
]
});
// sync collection as table to db
await db.sync();
```
### `getCollection()`
Gets a defined data table.
**Signature**
* `getCollection(name: string): Collection`
**Parameter**
| Name | Type | Default | Description |
| --- | --- | --- | --- |
| `name` | `string` | - | Table name |
**Example**
```ts
const collection = db.getCollection('books');
```
### `hasCollection()`
Check whether if a specified data table has been defined.
**Signature**
* `hasCollection(name: string): boolean`
**Parameter**
| Name | Type | Default | Description |
| --- | --- | --- | --- |
| `name` | `string` | - | Table name |
**Example**
```ts
db.collection({ name: 'books' });
db.hasCollection('books'); // true
db.hasCollection('authors'); // false
```
### `removeCollection()`
Remove a defined data table; remove from memory only. Call the `sync` method if it is needed to be persisted to the database.
**Signature**
* `removeCollection(name: string): void`
**Parameter**
| Name | Type | Default | Description |
| --- | --- | --- | --- |
| `name` | `string` | - | Table name |
**Event**
* `'beforeRemoveCollection'`: Trigger before removing the table.
* `'afterRemoveCollection'`: Trigger after removing the table
**Example**
```ts
db.collection({ name: 'books' });
db.removeCollection('books');
```
### `import()`
Load all files in the import file directory into memory as the configuration of collection.
**Signature**
* `async import(options: { directory: string; extensions?: ImportFileExtension[] }): Promise<Map<string, Collection>>`
**Parameter**
| Name | Type | Default | Description |
| --- | --- | --- | --- |
| `options.directory` | `string` | - | Path of directory to be imported |
| `options.extensions` | `string[]` | `['ts', 'js']` | Scan for specific suffixes |
**Example**
The collection defined by file `./collections/books.ts` is as below:
```ts
export default {
name: 'books',
fields: [
{
type: 'string',
name: 'title',
}
]
};
```
Import the relevant configurations when loading the plugin:
```ts
class Plugin {
async load() {
await this.app.db.import({
directory: path.resolve(__dirname, './collections'),
});
}
}
```
## Extended Registration and Access
### `registerFieldTypes()`
Register custom field types.
**Signature**
* `registerFieldTypes(fieldTypes: MapOf<typeof Field>): void`
**Parameter**
`fieldTypes` is a key-value pair, where key is the field type name and value is the field type class.
**Example**
```ts
import { Field } from '@nocobase/database';
class MyField extends Field {
// ...
}
db.registerFieldTypes({
myField: MyField,
});
```
### `registerModels()`
Register custom data model classes.
**Signature**
* `registerModels(models: MapOf<ModelStatic<any>>): void`
**Parameter**
`models` is a key-value pair, where key is the data model name and value is the data model class.
**Example**
```ts
import { Model } from '@nocobase/database';
class MyModel extends Model {
// ...
}
db.registerModels({
myModel: MyModel,
});
db.collection({
name: 'myCollection',
model: 'myModel'
});
```
### `registerRepositories()`
注册自定义数据仓库类。
**签名**
* `registerRepositories(repositories: MapOf<RepositoryType>): void`
**参数**
`repositories` 是一个键值对,键为数据仓库名称,值为数据仓库类。
**示例**
```ts
import { Repository } from '@nocobase/database';
class MyRepository extends Repository {
// ...
}
db.registerRepositories({
myRepository: MyRepository,
});
db.collection({
name: 'myCollection',
repository: 'myRepository'
});
```
### `registerOperators()`
注册自定义数据查询操作符。
**签名**
* `registerOperators(operators: MapOf<OperatorFunc>)`
**参数**
`operators` 是一个键值对,键为操作符名称,值为操作符比较语句生成函数。
**示例**
```ts
db.registerOperators({
$dateOn(value) {
return {
[Op.and]: [{ [Op.gte]: stringToDate(value) }, { [Op.lt]: getNextDay(value) }],
};
}
});
db.getRepository('books').count({
filter: {
createdAt: {
// registered operator
$dateOn: '2020-01-01',
}
}
});
```
### `getModel()`
获取已定义的数据模型类。如果没有在之前注册自定义模型类,将返回 Sequelize 默认的模型类。默认名称与 collection 定义的名称相同。
**签名**
* `getModel(name: string): Model`
**参数**
| 参数名 | 类型 | 默认值 | 描述 |
| --- | --- | --- | --- |
| `name` | `string` | - | 已注册的模型名 |
**示例**
```ts
db.registerModels({
books: class MyModel extends Model {}
});
const ModelClass = db.getModel('books');
console.log(ModelClass.prototype instanceof MyModel) // true
```
注:从 collection 中获取的模型类并不与注册时的模型类严格相等,而是继承自注册时的模型类。由于 Sequelize 的模型类在初始化过程中属性会被修改,所以 NocoBase 自动处理了这个继承关系。除类不相等以外,其他所有定义都可以正常使用。
### `getRepository()`
获取自定义的数据仓库类。如果没有在之前注册自定义数据仓库类,将返回 NocoBase 默认的数据仓库类。默认名称与 collection 定义的名称相同。
数据仓库类主要用于基于数据模型的增删改查等操作,参考 [数据仓库](/api/server/database/repository)。
**签名**
* `getRepository(name: string): Repository`
* `getRepository(name: string, relationId?: string | number): Repository`
**参数**
| 参数名 | 类型 | 默认值 | 描述 |
| --- | --- | --- | --- |
| `name` | `string` | - | 已注册的数据仓库名 |
| `relationId` | `string` \| `number` | - | 关系数据的外键值 |
当名称是形如 `'tables.relactions'` 的带关联的名称时,将返回关联的数据仓库类。如果提供了第二个参数,数据仓库在使用时(查询、修改等)会基于关系数据的外键值。
**示例**
假设有两张数据表_文章_与_作者_并且文章表中有一个外键指向作者表
```ts
const AuthorsRepo = db.getRepository('authors');
const author1 = AuthorsRepo.create({ name: 'author1' });
const PostsRepo = db.getRepository('authors.posts', author1.id);
const post1 = AuthorsRepo.create({ title: 'post1' });
asset(post1.authorId === author1.id); // true
```
## 数据库事件
### `on()`
监听数据库事件。
**签名**
* `on(event: string, listener: (...args: any[]) => void | Promise<void>): void`
**参数**
| 参数名 | 类型 | 默认值 | 描述 |
| --- | --- | --- | --- |
| event | string | - | 事件名称 |
| listener | Function | - | 事件监听器 |
事件名称默认支持 Sequelize 的 Model 事件。针对全局事件,通过 `<sequelize_model_global_event>` 的名称方式监听,针对单 Model 事件,通过 `<model_name>.<sequelize_model_event>` 的名称方式监听。
所有内置的事件类型的参数说明和详细示例参考 [内置事件](#内置事件) 部分内容。
### `off()`
移除事件监听函数。
**签名**
* `off(name: string, listener: Function)`
| 参数名 | 类型 | 默认值 | 描述 |
| --- | --- | --- | --- |
| name | string | - | 事件名称 |
| listener | Function | - | 事件监听器 |
**示例**
```ts
const listener = async (model, options) => {
console.log(model);
};
db.on('afterCreate', listener);
db.off('afterCreate', listener);
```
## 数据库操作
### `auth()`
数据库连接验证。可以用于确保应用与数据已建立连接。
**签名**
* `auth(options: QueryOptions & { retry?: number } = {}): Promise<boolean>`
**参数**
| 参数名 | 类型 | 默认值 | 描述 |
| --- | --- | --- | --- |
| `options?` | `Object` | - | 验证选项 |
| `options.retry?` | `number` | `10` | 验证失败时重试次数 |
| `options.transaction?` | `Transaction` | - | 事务对象 |
| `options.logging?` | `boolean \| Function` | `false` | 是否打印日志 |
**示例**
```ts
await db.auth();
```
### `reconnect()`
重新连接数据库。
**示例**
```ts
await db.reconnect();
```
### `closed()`
判断数据库是否已关闭连接。
**签名**
* `closed(): boolean`
### `close()`
关闭数据库连接。等同于 `sequelize.close()`
### `sync()`
同步数据库表结构。等同于 `sequelize.sync()`,参数参考 [Sequelize 文档](https://sequelize.org/api/v6/class/src/sequelize.js~sequelize#instance-method-sync)。
### `clean()`
清空数据库,将删除所有数据表。
**签名**
* `clean(options: CleanOptions): Promise<void>`
**参数**
| 参数名 | 类型 | 默认值 | 描述 |
| --- | --- | --- | --- |
| `options.drop` | `boolean` | `false` | 是否移除所有数据表 |
| `options.skip` | `string[]` | - | 跳过的表名配置 |
| `options.transaction` | `Transaction` | - | 事务对象 |
**示例**
移除除 `users` 表以外的所有表。
```ts
await db.clean({
drop: true,
skip: ['users']
})
```
## 包级导出
### `defineCollection()`
创建一个数据表的配置内容。
**签名**
* `defineCollection(name: string, config: CollectionOptions): CollectionOptions`
**参数**
| 参数名 | 类型 | 默认值 | 描述 |
| --- | --- | --- | --- |
| `collectionOptions` | `CollectionOptions` | - | 与所有 `db.collection()` 的参数相同 |
**示例**
对于要被 `db.import()` 导入的数据表配置文件:
```ts
import { defineCollection } from '@nocobase/database';
export default defineCollection({
name: 'users',
fields: [
{
type: 'string',
name: 'name',
},
],
});
```
### `extendCollection()`
扩展已在内存中的表结构配置内容,主要用于 `import()` 方法导入的文件内容。该方法是 `@nocobase/database` 包导出的顶级方法,不通过 db 实例调用。也可以使用 `extend` 别名。
**签名**
* `extendCollection(collectionOptions: CollectionOptions, mergeOptions?: MergeOptions): ExtendedCollectionOptions`
**参数**
| 参数名 | 类型 | 默认值 | 描述 |
| --- | --- | --- | --- |
| `collectionOptions` | `CollectionOptions` | - | 与所有 `db.collection()` 的参数相同 |
| `mergeOptions?` | `MergeOptions` | - | npm 包 [deepmerge](https://npmjs.com/package/deepmerge) 的参数 |
**示例**
原始 books 表定义books.ts
```ts
export default {
name: 'books',
fields: [
{ name: 'title', type: 'string' }
]
}
```
扩展 books 表定义books.extend.ts
```ts
import { extend } from '@nocobase/database';
// 再次扩展
export default extend({
name: 'books',
fields: [
{ name: 'price', type: 'number' }
]
});
```
以上两个文件如在调用 `import()` 时导入,通过 `extend()` 再次扩展以后books 表将拥有 `title``price` 两个字段。
此方法在扩展已有插件已定义的表结构时非常有用。
## 内置事件
数据库会在相应的生命周期触发以下对应的事件,通过 `on()` 方法订阅后进行特定的处理可满足一些业务需要。
### `'beforeSync'` / `'afterSync'`
当新的表结构配置(字段、索引等)被同步到数据库前后触发,通常在执行 `collection.sync()`(内部调用)时会触发,一般用于一些特殊的字段扩展的逻辑处理。
**签名**
```ts
on(eventName: `${string}.beforeSync` | 'beforeSync' | `${string}.afterSync` | 'afterSync', listener: SyncListener): this
```
**类型**
```ts
import type { SyncOptions, HookReturn } from 'sequelize/types';
type SyncListener = (options?: SyncOptions) => HookReturn;
```
**示例**
```ts
const users = db.collection({
name: 'users',
fields: [
{ type: 'string', name: 'username' }
]
});
db.on('beforeSync', async (options) => {
// do something
});
db.on('users.afterSync', async (options) => {
// do something
});
await users.sync();
```
### `'beforeValidate'` / `'afterValidate'`
创建或更新数据前会有基于 collection 定义的规则对数据的验证过程,在验证前后会触发对应事件。当调用 `repository.create()``repository.update()` 时会触发。
**签名**
```ts
on(eventName: `${string}.beforeValidate` | 'beforeValidate' | `${string}.afterValidate` | 'afterValidate', listener: ValidateListener): this
```
**类型**
```ts
import type { ValidationOptions } from 'sequelize/types/lib/instance-validator';
import type { HookReturn } from 'sequelize/types';
import type { Model } from '@nocobase/database';
type ValidateListener = (model: Model, options?: ValidationOptions) => HookReturn;
```
**示例**
```ts
db.collection({
name: 'tests',
fields: [
{
type: 'string',
name: 'email',
validate: {
isEmail: true,
},
}
],
});
// all models
db.on('beforeValidate', async (model, options) => {
// do something
});
// tests model
db.on('tests.beforeValidate', async (model, options) => {
// do something
});
// all models
db.on('afterValidate', async (model, options) => {
// do something
});
// tests model
db.on('tests.afterValidate', async (model, options) => {
// do something
});
const repository = db.getRepository('tests');
await repository.create({
values: {
email: 'abc', // checks for email format
},
});
// or
await repository.update({
filterByTk: 1,
values: {
email: 'abc', // checks for email format
},
});
```
### `'beforeCreate'` / `'afterCreate'`
创建一条数据前后会触发对应事件,当调用 `repository.create()` 时会触发。
**签名**
```ts
on(eventName: `${string}.beforeCreate` | 'beforeCreate' | `${string}.afterCreate` | 'afterCreate', listener: CreateListener): this
```
**类型**
```ts
import type { CreateOptions, HookReturn } from 'sequelize/types';
import type { Model } from '@nocobase/database';
export type CreateListener = (model: Model, options?: CreateOptions) => HookReturn;
```
**示例**
```ts
db.on('beforeCreate', async (model, options) => {
// do something
});
db.on('books.afterCreate', async (model, options) => {
const { transaction } = options;
const result = await model.constructor.findByPk(model.id, {
transaction
});
console.log(result);
});
```
### `'beforeUpdate'` / `'afterUpdate'`
更新一条数据前后会触发对应事件,当调用 `repository.update()` 时会触发。
**签名**
```ts
on(eventName: `${string}.beforeUpdate` | 'beforeUpdate' | `${string}.afterUpdate` | 'afterUpdate', listener: UpdateListener): this
```
**类型**
```ts
import type { UpdateOptions, HookReturn } from 'sequelize/types';
import type { Model } from '@nocobase/database';
export type UpdateListener = (model: Model, options?: UpdateOptions) => HookReturn;
```
**示例**
```ts
db.on('beforeUpdate', async (model, options) => {
// do something
});
db.on('books.afterUpdate', async (model, options) => {
// do something
});
```
### `'beforeSave'` / `'afterSave'`
创建或更新一条数据前后会触发对应事件,当调用 `repository.create()``repository.update()` 时会触发。
**签名**
```ts
on(eventName: `${string}.beforeSave` | 'beforeSave' | `${string}.afterSave` | 'afterSave', listener: SaveListener): this
```
**类型**
```ts
import type { SaveOptions, HookReturn } from 'sequelize/types';
import type { Model } from '@nocobase/database';
export type SaveListener = (model: Model, options?: SaveOptions) => HookReturn;
```
**示例**
```ts
db.on('beforeSave', async (model, options) => {
// do something
});
db.on('books.afterSave', async (model, options) => {
// do something
});
```
### `'beforeDestroy'` / `'afterDestroy'`
删除一条数据前后会触发对应事件,当调用 `repository.destroy()` 时会触发。
**签名**
```ts
on(eventName: `${string}.beforeDestroy` | 'beforeDestroy' | `${string}.afterDestroy` | 'afterDestroy', listener: DestroyListener): this
```
**类型**
```ts
import type { DestroyOptions, HookReturn } from 'sequelize/types';
import type { Model } from '@nocobase/database';
export type DestroyListener = (model: Model, options?: DestroyOptions) => HookReturn;
```
**示例**
```ts
db.on('beforeDestroy', async (model, options) => {
// do something
});
db.on('books.afterDestroy', async (model, options) => {
// do something
});
```
### `'afterCreateWithAssociations'`
创建一条携带层级关系数据的数据之后会触发对应事件,当调用 `repository.create()` 时会触发。
**签名**
```ts
on(eventName: `${string}.afterCreateWithAssociations` | 'afterCreateWithAssociations', listener: CreateWithAssociationsListener): this
```
**类型**
```ts
import type { CreateOptions, HookReturn } from 'sequelize/types';
import type { Model } from '@nocobase/database';
export type CreateWithAssociationsListener = (model: Model, options?: CreateOptions) => HookReturn;
```
**示例**
```ts
db.on('afterCreateWithAssociations', async (model, options) => {
// do something
});
db.on('books.afterCreateWithAssociations', async (model, options) => {
// do something
});
```
### `'afterUpdateWithAssociations'`
更新一条携带层级关系数据的数据之后会触发对应事件,当调用 `repository.update()` 时会触发。
**签名**
```ts
on(eventName: `${string}.afterUpdateWithAssociations` | 'afterUpdateWithAssociations', listener: CreateWithAssociationsListener): this
```
**类型**
```ts
import type { UpdateOptions, HookReturn } from 'sequelize/types';
import type { Model } from '@nocobase/database';
export type UpdateWithAssociationsListener = (model: Model, options?: UpdateOptions) => HookReturn;
```
**示例**
```ts
db.on('afterUpdateWithAssociations', async (model, options) => {
// do something
});
db.on('books.afterUpdateWithAssociations', async (model, options) => {
// do something
});
```
### `'afterSaveWithAssociations'`
创建或更新一条携带层级关系数据的数据之后会触发对应事件,当调用 `repository.create()``repository.update()` 时会触发。
**签名**
```ts
on(eventName: `${string}.afterSaveWithAssociations` | 'afterSaveWithAssociations', listener: SaveWithAssociationsListener): this
```
**类型**
```ts
import type { SaveOptions, HookReturn } from 'sequelize/types';
import type { Model } from '@nocobase/database';
export type SaveWithAssociationsListener = (model: Model, options?: SaveOptions) => HookReturn;
```
**示例**
```ts
db.on('afterSaveWithAssociations', async (model, options) => {
// do something
});
db.on('books.afterSaveWithAssociations', async (model, options) => {
// do something
});
```
### `'beforeDefineCollection'`
当定义一个数据表之前触发,如调用 `db.collection()` 时。
注:该事件是同步事件。
**签名**
```ts
on(eventName: 'beforeDefineCollection', listener: BeforeDefineCollectionListener): this
```
**类型**
```ts
import type { CollectionOptions } from '@nocobase/database';
export type BeforeDefineCollectionListener = (options: CollectionOptions) => void;
```
**示例**
```ts
db.on('beforeDefineCollection', (options) => {
// do something
});
```
### `'afterDefineCollection'`
当定义一个数据表之后触发,如调用 `db.collection()` 时。
注:该事件是同步事件。
**签名**
```ts
on(eventName: 'afterDefineCollection', listener: AfterDefineCollectionListener): this
```
**类型**
```ts
import type { Collection } from '@nocobase/database';
export type AfterDefineCollectionListener = (options: Collection) => void;
```
**示例**
```ts
db.on('afterDefineCollection', (collection) => {
// do something
});
```
### `'beforeRemoveCollection'` / `'afterRemoveCollection'`
当从内存中移除一个数据表前后触发,如调用 `db.removeCollection()` 时。
注:该事件是同步事件。
**签名**
```ts
on(eventName: 'beforeRemoveCollection' | 'afterRemoveCollection', listener: RemoveCollectionListener): this
```
**类型**
```ts
import type { Collection } from '@nocobase/database';
export type RemoveCollectionListener = (options: Collection) => void;
```
**示例**
```ts
db.on('beforeRemoveCollection', (collection) => {
// do something
});
db.on('afterRemoveCollection', (collection) => {
// do something
});
```