TypeORM

tenancyjs-adapter-typeorm provides all three strategies on PostgreSQL plus adapter-enforced row-level and database-per-tenant on MySQL. This page shows it wired end to end with Express; for another framework, swap only the integration (see below).

Install

npm install tenancyjs-core tenancyjs-adapter-typeorm tenancyjs-integration-express typeorm

Wire it into your app

import { TenancyManager } from "tenancyjs-core";
import { createTypeOrmTenancy } from "tenancyjs-adapter-typeorm";
import { dataSource, Order } from "./data-source";

export interface Tenant {
  readonly id: string;
}

export const manager = new TenancyManager<Tenant>();

export const tenancy = createTypeOrmTenancy({
  manager,
  dataSource,
  tenantEntities: [
    {
      entity: Order,
      table: "app.orders",
      tenantProperty: "tenantId",
      tenantColumn: "tenant_id",
    },
  ],
});

await tenancy.validate();

import express from "express";
import { createExpressTenancyMiddleware } from "tenancyjs-integration-express";
import { manager, tenancy } from "./tenancy";
import { Order } from "./data-source";

const app = express();

app.use(
  createExpressTenancyMiddleware({
    manager,
    resolver, // a TenantResolutionChain (tenancyjs-identifiers) - see the Express guide
  }),
);

app.get("/orders", async (_req, res) => {
  const orders = await tenancy.run((client) =>
    client.repository(Order).findBy({ status: "open" }),
  );
  res.json(orders); // only the current tenant's rows
});

Other strategies

Schema mode requires unqualified entity metadata and table config:

createTypeOrmTenancy({
  manager,
  dataSource,
  strategy: "schemaPerTenant",
  schema: (tenant) => tenant.schemaName,
  tenantEntities: [{ entity: Order, table: "orders" }],
});

Database mode leases initialized tenant DataSource objects from the bounded cache:

createTypeOrmTenancy({
  manager,
  dataSource: landlordDataSource,
  strategy: "databasePerTenant",
  tenantEntities: [{ entity: Order, table: "orders" }],
  connection: (tenant) => ({
    key: tenant.databaseKey,
    create: () => createTenantDataSource(tenant.databaseSecretRef),
  }),
});

Call validate() before serving traffic and close() during shutdown. Native managers, query builders, relations, raw SQL, schema sync, and migrations remain outside the protected surface.

For MySQL, pass dialect: "mysql". Row isolation is experimental and adapter-enforced because MySQL has no RLS. MySQL schema and database are synonyms, so use databasePerTenant instead of schema mode.

Full query freedom: unrestricted()

unrestricted() returns a tenant-scoped EntityManager - full query builder, relations, and raw SQL. It's available in the two scopes where the database itself keeps a query inside the tenant: database-per-tenant (the leased connection is the tenant's own database) and forced-RLS row-level on PostgreSQL (the scoped EntityManager runs under a non-BYPASSRLS role bound by the validated RLS policy, so it cannot cross tenants). It's still refused in schema-per-tenant, central mode, and MySQL row-level (no RLS backstop) - there the protected client is the only guard, so it can't let through what it can't prove is tenant-safe (see Limitations):

const report = await tenancy.run(async (client) => {
  // The raw, tenant-scoped EntityManager - query builder, relations, raw SQL.
  const manager = client.unrestricted();

  return manager
    .createQueryBuilder(Order, "order")
    .innerJoin("order.customer", "customer")
    .where("order.total > :min", { min: 1000 })
    .select(["order.id", "customer.name"])
    .getRawMany();
});

Use a different framework

Keep the adapter half; only swap the integration import: