Catalyze TypeScript API iterations for single-tenant deployments

v1.ts

const project = new PulumiProject('customers');

export const deployCustomers = new Pipeline('deploy-customers', {
  stages: [
    new DeploymentStage('deploy', { atomic: true })
      .withEnvironmentGroup(environmentGroups.customers)
      .forEachEnvironment((environment, stage) => {
        stage.addStep(
          new InfrastructureDeployStep('infrastructure', {
            target: new PulumiLocalStack('stack', {
              project,
            }),
          }),
        );

        const databaseMigrationStep = new DatabaseMigrationStep('database', {
          target: new Database('database'),
        });
        stage.addStep(databaseMigrationStep);

        stage.addStep(
          new ApplicationDeployStep('customer', {
            target: new Application('customer'),
            rollbackStepsOnFailure: [databaseMigrationStep],
          }),
        );
      }),
  ],
});

v2.ts

const customers = new Tenants('customers', 
  // can be remote
  tenants: [
    new Tenant('apple', {
      variables: {},
    }),
    new Tenant('google', {
      variables: {},
    }),
    new Tenant('microsoft', {
      variables: {},
    }),
  ],
});

const infrastructure = new PulumiProject('customers');

const database = new Database('customer');

const application = new Application('customer');

export const deployCustomers = new Pipeline('deploy-customers');

const deploymentStage = deployCustomers.stage('deploy')
  .deployment({ atomic: true })
  .tenants(customers);

deploymentStage.tenants.forEach(tenant => {
  infrastructure.stack(tenant.name).deploy();

  const databaseMigration = database.migrate(tenant.name);

  application.deploy(tenant.name)
    .rollbackOnFailure({ self: true, steps: [databaseMigration] });
  });
});