Contribute to help us improve!

Are there edge cases or problems that we didn't consider? Is there a technical pitfall that we should add? Did we miss a comma in a sentence?

If you have any input for us, we would love to hear from you and appreciate every contribution. Our goal is to learn from projects for projects such that nobody has to reinvent the wheel.

Let's collect our experiences together to make room to explore the novel!

To contribute click on Contribute to this page on the toolbar.

TypeORM

TypeORM is the default ORM provided by devon4node. It supports MySQL, MariaDB, Postgres, CockroachDB, SQLite, Microsoft SQL Server, Oracle, sql.js relational database and also supports MongoDB NoSQL database.

Add TypeORM support to a devon4node application is very easy: you only need to execute the command nest g -c @devon4node/schematics typeorm and it will add all required dependencies to the project and also imports the @nestjs/typeorm module.

For more information about TypeORM and the integration with NestJS you can visit TypeORM webpage, TypeORM GitHub repository and NestJS TypeORM documentation page

Configuration

When you have the configuration module, the TypeORM generator will add one property in order to be able to configure the database depending on the environment. Example:

database: {
  type: 'sqlite',
  database: ':memory:',
  synchronize: false,
  migrationsRun: true,
  logging: true,
  entities: ['dist/**/*.entity.js'],
  migrations: ['dist/migration/**/*.js'],
  subscribers: ['dist/subscriber/**/*.js'],
  cli: {
    entitiesDir: 'src/entity',
    migrationsDir: 'src/migration',
    subscribersDir: 'src/subscriber',
  },
},

This object is a TypeORM ConnectionOptions. For fore information about it visit the TypeORM Connection Options page.

There is also a special case: the default configuration. As the devon4node CLI need the database configuration when you use the devon4node db command, we also provide the ormconfig.json file. In this file you must put the configuration for you local environment. In order to do not have duplicated the configuration for local environment, in the default config file the database property is set-up like:

database: require('../../ormconfig.json'),

So, you only need to maintain the ormconfig.json file for the local environment.

Entity

Entity is a class that maps to a database table. The devon4node schematics has a generator to create new entities. You only need to execute the command nest g -c @devon4node/schematics entity <entity-name> and it generate the entity.

In the entity, you must define all columns, relations, primary keys of your database table. By default, devon4node provides a class named BaseEntity. All entities created with the devon4node schematics will extends the BaseEntity. This entity provides you some common columns:

id: the primary key of you table
version: the version of the entry (used for auditing purposes)
createdAt: creation date of the entry (used for auditing purposes)
updatedAt: last update date of the entry (used for auditing purposes)

For more information about Entities, please visit the TypeORM entities page

Repository

With repositories, you can manage (insert, update, delete, load, etc.) a concrete entity. Using this pattern, we have separated the data (Entities) from the methods to manage it (Repositories).

To use a repository you only need to:

Import it in the module as follows:
```
@Module({
  imports: [TypeOrmModule.forFeature([Employee])],
})
```
if you generate the entities with the devon4node schematic, this step is not necessary, devon4node schematic will do it for you.

Inject the repository as dependency in your service:

constructor(@InjectRepository(Employee) employeeRepository: Repository<Employee>) {}

You can see more details in the NestJS database and NestJS TypeORM documentation pages.