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Prisma adapter

Installation​

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

Registration​

ClsModule.forRoot({
    plugins: [
        new ClsPluginTransactional({
            imports: [
              // module in which the PrismaClient is provided
              PrismaModule
            ],
            adapter: new TransactionalAdapterPrisma({
                // the injection token of the PrismaClient
                prismaInjectionToken: PrismaService,
            }),
        }),
    ],
}),
important

The prismaInjectionToken is the token under which an instance of PrismaClient provided. Usually, in Nest, this the custom PrismaService class which extends PrismaClient and is exported from a custom module.

Typing & usage​

The tx property on the TransactionHost<TransactionalAdapterPrisma> refers to the transactional PrismaClient instance when used in a transactional context. It is the instance that is passed to the prisma.$transaction(( tx ) => { ... }) callback.

Outside of a transactional context, it refers to the regular PrismaClient instance (but is typed as the transactional one).

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<TransactionalAdapterPrisma>,
    ) {}

    async getUserById(id: number) {
        // txHost.tx is typed as the transactional PrismaClient
        return this.txHost.tx.user.findUnique({ where: { id } });
    }

    async createUser(name: string) {
        return this.txHost.tx.user.create({
            data: { name: name, email: `${name}@email.com` },
        });
    }
}

Custom client type​

Since 1.1.0

By default, the adapter assumes that the Prisma client is available as @prisma/client. If you have a different setup, or you use some Prisma client extensions, you can provide a custom type for the client as a generic parameter of the adapter.

TransactionalAdapterPrisma<CustomPrismaClient>;

This type will need to be used whenever you inject the TransactionHost or Transaction

private readonly txHost: TransactionHost<TransactionalAdapterPrisma<CustomPrismaClient>>

Which becomes pretty verbose, so it's recommended to create a custom type alias for the adapter.

important

Please make sure you set up the module with the custom prisma client and not the default one, otherwise you would get a runtime error.

new ClsPluginTransactional({
    imports: [
        // module in which the PrismaClient is provided
        PrismaModule
    ],
    adapter: new TransactionalAdapterPrisma({
        // the injection token of the PrismaClient
        prismaInjectionToken: CUSTOM_PRISMA_CLIENT_TOKEN,
    }),
}),