Redis OM for Node.js 简介

适用于 JavaScript 和 TypeScript 的快速简便的对象映射

我写了一个东西——好吧，实际上我们几个人写了东西——我只是写了 Node.js 版本。我认为这是一个非常酷的东西，值得您关注，我对此感到兴奋。我要谈论的东西：Redis OM for Node.js。

什么是 Redis OM？ Redis OM 是一个库，通过将 Redis 数据结构直接映射到您的代码，可以轻松使用 Redis。 OM 代表对象映射，但我们计划将来做更多的事情。

请继续阅读以了解更多详情。

比快更快

您可能已经知道 Redis 速度很快 - 比快更快 - 它存储您的程序关心的各种东西：哈希、列表、集合等等。这些是我作为程序员所思考的结构。当我向一个没有经验的技术人员解释 Redis 是什么时，我会告诉他们 Redis 是你在大学里学到的所有数据结构，并在它们前面放了一个线路协议。

特性通过引入您的程序关心的新的数据结构，使 Redis 更加出色（是的，我知道这不是一个词）。概率的添加了概率数据结构，如 Bloom 和 Cuckoo 过滤器。

最出色的模块

但是有两个模块特别使得 Redis 成为每个程序员都想要的强大的内存数据库：JSON 和搜索和查询。

JSON 将层次结构带到了表中。哈希很棒，但是如果你想在哈希中嵌入哈希怎么办？ JSON 通过允许你将我的分层数据存储在 JSON 文档中来满足你的需求。

与此同时，搜索和查询让你查找你关心的数据结构。当然，你可以使用集合创建手动索引，但这种方法是有限的和手动的。呸。搜索和查询让你编写查询来直接查找你想要的数据。

结合起来，搜索和查询以及 JSON 使 Redis 成为一个非常好的文档数据库。你获得了你想要的层次结构，并且能够找到你关心的东西。两全其美。

事实上，我们认为这是一个如此美味的组合，我们正在将它们组合在一起，并称它们为 JSON。

Redis OM for Node.js

搜索和查询的查询语言非常强大。非常强大。它允许你以各种复杂的方式搜索 Redis 中的哈希和 JSON 文档。当我需要所有这些力量时，它非常酷。但有时我不需要所有这些力量。而且我是一个懒惰的开发者——我希望它尽可能简单（并且没有更容易的）。

当我编写 Redis OM for Node.js 时，我试图尽可能地简化事情。 Redis OM 通过将哈希和 JSON 文档映射到你定义的类，从而使将 Redis 添加到你的 Node.js 应用程序变得简单。没有复杂的命令，只有具有流畅接口的纯代码。看看。

定义一个实体

class Album extends Entity {}

let schema = new Schema(Album, {
  artist: { type: 'string' },
  title: { type: 'string', textSearch: true },
  year: { type: 'number' }
});

创建一个新实体并保存它

let album = repository.createEntity()
album.artist = "Mushroomhead"
album.title = "The Righteous & The Butterfly"
album.year = 2014
await repository.save(album)

搜索匹配的实体

let albums = await repository.search()
  .where('artist').equals('Mushroomhead')
  .and('title').matches('butterfly')
  .and('year').is.greaterThan(2000).returnAll()

既然我写了这个库，我有点偏见，但我认为这非常酷！让我们仔细看看这个语法，了解它是如何工作的。

它是如何工作的

在 Redis OM for Node.js 中，你需要关心四个类。它们是 Entity、Schema、Client 和 Repository。

import { Entity, Schema, Client, Repository } from 'redis-om'

class Album extends Entity {}

let schema = new Schema(Album, {
  artist: { type: 'string' },
  title: { type: 'string' },
  year: { type: 'number' },
  genres: { type: 'array' },
  outOfPublication: { type: 'boolean' }
})

let client = new Client()
await client.open('redis://localhost:6379')

let repository = new Repository(schema, client)

let album, id

// create an entity and save it
album = repository.createEntity()

album.artist = "Mushroomhead"
album.title = "The Righteous & The Butterfly"
album.year = 2014
album.genres = [ 'metal' ]
album.outOfPublication = true

id = await repository.save(album) // '01FJYWEYRHYFT8YTEGQBABJ43J'

// read an entity
album = await repository.fetch('01FJYWEYRHYFT8YTEGQBABJ43J')

// update an entity
album.genres = [ 'metal', 'nu metal', 'avantgarde' ]
album.outOfPublication = false

id = await repository.save(album) // '01FJYWEYRHYFT8YTEGQBABJ43J'

// delete an entity
await repository.remove('01FJYWEYRHYFT8YTEGQBABJ43J')

let albums = await repository.search()
  .where('artist').equals('Mushroomhead')
  .and('title').matches('butterfly')
  .and('year').is.greaterThan(2000).returnAll()

实体是你使用的类。正在创建、读取、更新和删除的东西。正在搜索的东西。任何扩展 Entity 的类都是一个实体。通常，你将使用一行代码定义一个实体，但你也可以在其中添加自定义逻辑

import { Entity, Schema, Client, Repository } from 'redis-om'

class Album extends Entity {}

let schema = new Schema(Album, {
  artist: { type: 'string' },
  title: { type: 'string' },
  year: { type: 'number' },
  genres: { type: 'array' },
  outOfPublication: { type: 'boolean' }
})

let client = new Client()
await client.open('redis://localhost:6379')

let repository = new Repository(schema, client)

let album, id

// create an entity and save it
album = repository.createEntity()

album.artist = "Mushroomhead"
album.title = "The Righteous & The Butterfly"
album.year = 2014
album.genres = [ 'metal' ]
album.outOfPublication = true

id = await repository.save(album) // '01FJYWEYRHYFT8YTEGQBABJ43J'

// read an entity
album = await repository.fetch('01FJYWEYRHYFT8YTEGQBABJ43J')

// update an entity
album.genres = [ 'metal', 'nu metal', 'avantgarde' ]
album.outOfPublication = false

id = await repository.save(album) // '01FJYWEYRHYFT8YTEGQBABJ43J'

// delete an entity
await repository.remove('01FJYWEYRHYFT8YTEGQBABJ43J')

let albums = await repository.search()
  .where('artist').equals('Mushroomhead')
  .and('title').matches('butterfly')
  .and('year').is.greaterThan(2000).returnAll()

Schema定义了你的实体上的字段、它们的类型以及它们如何在内部映射到 Redis。默认情况下，实体映射到 Redis 中的哈希，但你也可以将它们映射到 JSON 文档

import { Entity, Schema, Client, Repository } from 'redis-om'

class Album extends Entity {}

let schema = new Schema(Album, {
  artist: { type: 'string' },
  title: { type: 'string' },
  year: { type: 'number' },
  genres: { type: 'array' },
  outOfPublication: { type: 'boolean' }
})

let client = new Client()
await client.open('redis://localhost:6379')

let repository = new Repository(schema, client)

let album, id

// create an entity and save it
album = repository.createEntity()

album.artist = "Mushroomhead"
album.title = "The Righteous & The Butterfly"
album.year = 2014
album.genres = [ 'metal' ]
album.outOfPublication = true

id = await repository.save(album) // '01FJYWEYRHYFT8YTEGQBABJ43J'

// read an entity
album = await repository.fetch('01FJYWEYRHYFT8YTEGQBABJ43J')

// update an entity
album.genres = [ 'metal', 'nu metal', 'avantgarde' ]
album.outOfPublication = false

id = await repository.save(album) // '01FJYWEYRHYFT8YTEGQBABJ43J'

// delete an entity
await repository.remove('01FJYWEYRHYFT8YTEGQBABJ43J')

let albums = await repository.search()
  .where('artist').equals('Mushroomhead')
  .and('title').matches('butterfly')
  .and('year').is.greaterThan(2000).returnAll()

当你创建一个 Schema 时，它会修改你传递给它的 Entity，为定义的属性添加 getter 和 setter。这些 getter 和 setter 接受和返回的类型由上面的 type 属性定义。

客户端将你连接到 Redis。客户端具有打开、关闭和针对 Redis 执行原始命令的方法。你主要使用 open 和 close

import { Entity, Schema, Client, Repository } from 'redis-om'

class Album extends Entity {}

let schema = new Schema(Album, {
  artist: { type: 'string' },
  title: { type: 'string' },
  year: { type: 'number' },
  genres: { type: 'array' },
  outOfPublication: { type: 'boolean' }
})

let client = new Client()
await client.open('redis://localhost:6379')

let repository = new Repository(schema, client)

let album, id

// create an entity and save it
album = repository.createEntity()

album.artist = "Mushroomhead"
album.title = "The Righteous & The Butterfly"
album.year = 2014
album.genres = [ 'metal' ]
album.outOfPublication = true

id = await repository.save(album) // '01FJYWEYRHYFT8YTEGQBABJ43J'

// read an entity
album = await repository.fetch('01FJYWEYRHYFT8YTEGQBABJ43J')

// update an entity
album.genres = [ 'metal', 'nu metal', 'avantgarde' ]
album.outOfPublication = false

id = await repository.save(album) // '01FJYWEYRHYFT8YTEGQBABJ43J'

// delete an entity
await repository.remove('01FJYWEYRHYFT8YTEGQBABJ43J')

let albums = await repository.search()
  .where('artist').equals('Mushroomhead')
  .and('title').matches('butterfly')
  .and('year').is.greaterThan(2000).returnAll()

实例化 Repository 需要 Schema 和 Client。 Repositories提供读取、写入和删除实体的方法。以及搜索它们的方法

import { Entity, Schema, Client, Repository } from 'redis-om'

class Album extends Entity {}

let schema = new Schema(Album, {
  artist: { type: 'string' },
  title: { type: 'string' },
  year: { type: 'number' },
  genres: { type: 'array' },
  outOfPublication: { type: 'boolean' }
})

let client = new Client()
await client.open('redis://localhost:6379')

let repository = new Repository(schema, client)

let album, id

// create an entity and save it
album = repository.createEntity()

album.artist = "Mushroomhead"
album.title = "The Righteous & The Butterfly"
album.year = 2014
album.genres = [ 'metal' ]
album.outOfPublication = true

id = await repository.save(album) // '01FJYWEYRHYFT8YTEGQBABJ43J'

// read an entity
album = await repository.fetch('01FJYWEYRHYFT8YTEGQBABJ43J')

// update an entity
album.genres = [ 'metal', 'nu metal', 'avantgarde' ]
album.outOfPublication = false

id = await repository.save(album) // '01FJYWEYRHYFT8YTEGQBABJ43J'

// delete an entity
await repository.remove('01FJYWEYRHYFT8YTEGQBABJ43J')

let albums = await repository.search()
  .where('artist').equals('Mushroomhead')
  .and('title').matches('butterfly')
  .and('year').is.greaterThan(2000).returnAll()

一旦我们有了 repository，我们就可以使用它来创建、读取、更新和删除实体。在这里，我正在用我最喜欢的 Mushroomhead 专辑来做这件事

import { Entity, Schema, Client, Repository } from 'redis-om'

class Album extends Entity {}

let schema = new Schema(Album, {
  artist: { type: 'string' },
  title: { type: 'string' },
  year: { type: 'number' },
  genres: { type: 'array' },
  outOfPublication: { type: 'boolean' }
})

let client = new Client()
await client.open('redis://localhost:6379')

let repository = new Repository(schema, client)

let album, id

// create an entity and save it
album = repository.createEntity()

album.artist = "Mushroomhead"
album.title = "The Righteous & The Butterfly"
album.year = 2014
album.genres = [ 'metal' ]
album.outOfPublication = true

id = await repository.save(album) // '01FJYWEYRHYFT8YTEGQBABJ43J'

// read an entity
album = await repository.fetch('01FJYWEYRHYFT8YTEGQBABJ43J')

// update an entity
album.genres = [ 'metal', 'nu metal', 'avantgarde' ]
album.outOfPublication = false

id = await repository.save(album) // '01FJYWEYRHYFT8YTEGQBABJ43J'

// delete an entity
await repository.remove('01FJYWEYRHYFT8YTEGQBABJ43J')

let albums = await repository.search()
  .where('artist').equals('Mushroomhead')
  .and('title').matches('butterfly')
  .and('year').is.greaterThan(2000).returnAll()

我们也可以使用它来搜索实体

import { Entity, Schema, Client, Repository } from 'redis-om'

class Album extends Entity {}

let schema = new Schema(Album, {
  artist: { type: 'string' },
  title: { type: 'string' },
  year: { type: 'number' },
  genres: { type: 'array' },
  outOfPublication: { type: 'boolean' }
})

let client = new Client()
await client.open('redis://localhost:6379')

let repository = new Repository(schema, client)

let album, id

// create an entity and save it
album = repository.createEntity()

album.artist = "Mushroomhead"
album.title = "The Righteous & The Butterfly"
album.year = 2014
album.genres = [ 'metal' ]
album.outOfPublication = true

id = await repository.save(album) // '01FJYWEYRHYFT8YTEGQBABJ43J'

// read an entity
album = await repository.fetch('01FJYWEYRHYFT8YTEGQBABJ43J')

// update an entity
album.genres = [ 'metal', 'nu metal', 'avantgarde' ]
album.outOfPublication = false

id = await repository.save(album) // '01FJYWEYRHYFT8YTEGQBABJ43J'

// delete an entity
await repository.remove('01FJYWEYRHYFT8YTEGQBABJ43J')

let albums = await repository.search()
  .where('artist').equals('Mushroomhead')
  .and('title').matches('butterfly')
  .and('year').is.greaterThan(2000).returnAll()

并且，为了你复制和粘贴的方便，这里是将该样本作为一个大的代码块

import { Entity, Schema, Client, Repository } from 'redis-om'

class Album extends Entity {}
let schema = new Schema(Album, {
  artist: { type: 'string' },
  title: { type: 'string' },
  year: { type: 'number' },
  genres: { type: 'array' },
  outOfPublication: { type: 'boolean' }
})

let client = new Client()
await client.open('redis://localhost:6379')

let repository = new Repository(schema, client)

let album, id

// create an entity and save it
album = repository.createEntity()

album.artist = "Mushroomhead"
album.title = "The Righteous & The Butterfly"
album.year = 2014
album.genres = [ 'metal' ]
album.outOfPublication = true

id = await repository.save(album) // '01FJYWEYRHYFT8YTEGQBABJ43J'

// read an entity
album = await repository.fetch('01FJYWEYRHYFT8YTEGQBABJ43J')

// update an entity
album.genres = [ 'metal', 'nu metal', 'avantgarde' ]
album.outOfPublication = false

id = await repository.save(album) // '01FJYWEYRHYFT8YTEGQBABJ43J'

// delete an entity
await repository.remove('01FJYWEYRHYFT8YTEGQBABJ43J')

let albums = await repository.search()
  .where('artist').equals('Mushroomhead')
  .and('title').matches('butterfly')
  .and('year').is.greaterThan(2000).returnAll()

这就是 Redis OM for Node.js，正如他们所说，简而言之。