This package adds DynamoDB support to TypeORM. It works by wrapping TypeORM. Supports Typeorm version 0.3+
To get started using NPM, you can use the following commands:
npm install --save typeorm-dynamodb
In dynamodb we don't really "open" a connection. However, we will need to read in all the entities so TypeORM knows about them.
There are two easy ways to initialized TypeORM.
import { datasourceManager } from 'typeorm-dynamodb'
import { User } from '../entities/user.ts'
const run = async () => {
await datasourceManager.open({
entities: [User],
synchronize: false // true will attempt to create tables
})
// now you can read / write to dynamodb
}import express from 'express'
import { datasourceInitializer, environmentUtils, pageableRoutes } from 'typeorm-dynamodb'
import { User } from '../entities/user'
const app = express()
app.use(datasourceInitializer({
entities: [User],
synchronize: environmentUtils.isLocal()
}))
app.use(pageableRoutes)
// ... continue with Express configurationThis will automatically parse query string parameters "page", "size" and "sort" and populate a req.pageable object. You can pass pageable straight through to your findPage repository method to pull back a limited result set.
import { Entity, PrimaryColumn, Column } from 'typeorm'
import { GlobalSecondaryIndex } from 'typeorm-dynamodb'
@Entity({ name: 'user' })
@GlobalSecondaryIndex({ name: 'ageIndex', partitionKey: 'age', sortKey: ['lastname','firstname'] })
export class User extends BaseEntity {
@PrimaryColumn({ name: 'id', type: 'varchar' })
id: string
@Column({ name: 'firstname', type: 'varchar' })
firstname: string
@Column({ name: 'lastname', type: 'varchar' })
lastname: string
@Column({ name: 'age', type: 'varchar' })
age: string
}import { EntityRepository } from 'typeorm'
import { PagingAndSortingRepository } from 'typeorm-repository'
import { User } from '../entities/user'
export class UserRepository extends PagingAndSortingRepository<User> {
}import { getRepository } from './datasource-manager'
import { DataSource } from 'typeorm/data-source/DataSource'
const repository = getRepository(User)import { User } from '../entities/user'
import { getRepository } from 'typeorm-dynamodb'
export class UserService {
async get (id: string) {
return getRepository(User).get(id)
}
async put (user: User) {
await getRepository(User).put(user)
}
async delete (id: string) {
await getRepository(User).delete({ id })
}
async findPage (criteria: any, pageable: Pageable) {
const repository = getRepository(User)
if (criteria.age) {
return repository.findPage({
index: 'ageIndex',
where: {
age: criteria.age
}
}, pageable)
}
return repository.findPage({}, pageable)
}
}In the User example the GlobalSecondaryIndex annotation allows you to use the dynamodb query method. It's extremely important to use an index whenever you are querying to avoid full table scans.
When new records are written to the database a column will be populated automatically that will store the value needed by the index.
For example, the sort column ["lastname","firstname"] will automatically populate a column "lastname#firstname" when the record is
saved to the database. Magic!