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Knex adapter

Installation​

npm install @nestjs-cls/transactional-adapter-knex

Registration​

ClsModule.forRoot({
    plugins: [
        new ClsPluginTransactional({
            imports: [
              // module in which Knex is provided
              KnexModule
            ],
            adapter: new TransactionalAdapterKnex({
                // the injection token of the Knex client instance
                knexInstanceToken: KNEX,
            }),
        }),
    ],
}),

Typing & usage​

The tx property on the TransactionHost<TransactionalAdapterKnex> is typed as Knex.

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');
        const foundUser = await this.userRepository.getUserById(user.id);
        assert(foundUser.id === user.id);
    }
}
user.repository.ts
@Injectable()
class UserRepository {
    constructor(
        private readonly txHost: TransactionHost<TransactionalAdapterKnex>,
    ) {}

    async getUserById(id: number) {
        // txHost.tx is typed as Knex
        return this.txHost.tx('user').where({ id }).first();
    }

    async createUser(name: string) {
        return this.txHost
            .tx('user')
            .insert({ name: name, email: `${name}@email.com` })
            .returning('*');
    }
}