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Pg-promise adapter

Installation​

npm install @nestjs-cls/transactional-adapter-pg-promise

Registration​

import { txMode } from 'pg-promise'

ClsModule.forRoot({
    plugins: [
        new ClsPluginTransactional({
            imports: [
              // module in which the database instance is provided
              DbModule
            ],
            adapter: new TransactionalAdapterPgPromise({
                // the injection token of the database instance
                dbInstanceToken: DB,

                // default transaction options (optional)
                defaultTxOptions: { mode: new txMode.TransactionMode({ tiLevel: txMode.isolationLevel.serializable }) }
            }),
        }),
    ],
}),

Typing & usage​

The tx property on the TransactionHost<TransactionalAdapterPgPromise> is typed as Database.

Example​

user.service.ts
@Injectable()
class UserService {
    constructor(private readonly userRepository: UserRepository) {}

    @Transactional()
    async runTransaction() {
        // both methods are executed in the same transaction
        const user = await this.userRepository.createUser(
            'John',
            'john@acme.com',
        );
        const foundUser = await this.userRepository.getUserById(user.id);
        assert(foundUser.id === user.id);
    }
}
user.repository.ts
@Injectable()
class UserRepository {
    constructor(
        private readonly txHost: TransactionHost<TransactionalAdapterPgPromise>,
    ) {}

    async getUserById(id: number) {
        // txHost.tx is typed as Database
        return this.txHost.tx.one(`SELECT * FROM user WHERE id = $1`, [id]);
    }

    async createUser(name: string, email: string) {
        return this.txHost.tx.none(
            `INSERT INTO user (name, email) VALUES ($1, $2)`,
            [name, email],
        );
    }
}