@knestjs/core

Knestjs

Knestjs search to be a Nestjs ORM in which you write the models once and only once. This is done creating migrations automatically from the models that you create.

How to use it

1. Register the core module in your app module like so:

@Module({
  imports: [
    KnestModule.forRoot({
         db: {
             client: 'sqlite3',
             connection: {
                 filename: ':memory:'
             },
             useNullAsDefault: true,
         },
         migrations: {
             folder: `${__dirname}/../../migrations`
         }
     }),
 ]
})
export class AppModule {}

This will configure knex with your db connection.

2. Create some model:

@Table({
    tableName: 'user'
})
export class UserModel {
    @Column({
        type: 'int',
        autoincrement: true,
        nullable: false
    })
    id!: number

    @Column({
        type: 'varchar',
        length: 255,
        nullable: false
    })
    user!: string;
}

This will create a table with a column id, that is a number autoincrement, and a column user of type varchar.

3. Register the models to your feature modules.

You can use the MigrationService to register the models, creating the TableSnapshotFactory with the module. But I recommend use a module like @knestjs/objection that uses Objection for providing the models, and also will provide you the tools to register the models easily.

How to handle the migrations?

Autogenerate migrations

You need to run the method makeMigrations from the MigrationService exported in @knestjs/core. You can use something like nestjs-command to provide a cli application for your project, you can use that cli application to run the migrations too.

How to run the migrations

The migrations are configured in knextjs by knestjs. You can retrieve the knextjs instance with the constant KNEX_INSTANCE from nestjs, and use the migrations API of knexjs.

Example

Take a look at the sample project cli module, that uses nestjs-command to provide a cli interface for the migrations