API Overview

This page enumerates the public surface of nest-warden's three subpath exports. Every symbol below is also documented in the source via JSDoc — your IDE / tsdoc / API extractor will pull the detailed signatures from there. A future iteration of the docs site will auto-generate per-symbol pages from JSDoc.

nest-warden (core, isomorphic)

Types

  • TenantContext<TId extends TenantIdValue = string> — request-scope identity bag.
  • TenantIdValue = string | number — admissible tenant ID types.
  • TenantAbility<A, C> — public alias for MongoAbility<A, C> produced by the builder.
  • Relationship<TFrom, TTo> — graph edge declaration.
  • RelatedToCondition — the $relatedTo operator value shape.
  • RelationshipPath — resolved sequence of hops returned by graph lookups.

Classes

  • TenantAbilityBuilder<TAbility, TId> — the auto-tenant-scoped builder.
    • .can, .cannot — auto-scoped rule additions (CASL-compatible signature).
    • .crossTenant.can, .crossTenant.cannot — explicit cross-tenant opt-out.
    • .build(options?) — runs validateTenantRules then delegates to CASL.
    • .tenantField, .tenantContext — read-only accessors.
  • RelationshipGraph — registry of relationships + BFS path resolver.
    • .define(relationship) — add a relationship; throws on duplicate names.
    • .has(name), .get(name), .all() — lookups.
    • .path(from, to, options?) — BFS shortest path.
    • .resolvePath(names) — validate and resolve a hand-specified path.

Resolver factories

  • foreignKey(options) — 1:N or N:1 via FK column.
  • joinTable(options) — M:N via junction table.
  • custom(options) — escape hatch with raw SQL fragment.

Helpers

  • validateTenantRules(rules, options) — assert tenant-predicate presence.
  • tenantConditionsMatcher — alias for CASL's mongoQueryMatcher.
  • createTenantConditionsMatcher({ graph }) — matcher that handles $relatedTo.
  • evaluateRelatedTo(subject, condition, graph) — forward-direction $relatedTo check.
  • markCrossTenant(rule), isCrossTenantRule(rule) — opt-out marker helpers.
  • createTenantAbility — re-export of createMongoAbility for parity.

Errors

  • MultiTenantCaslError — base class; check via instanceof.
  • CrossTenantViolationError — rule lacks tenant predicate at .build().
  • MissingTenantContextError — TenantContextService.get() before resolution.
  • UnsupportedOperatorError — TypeORM compiler hit an unknown operator.
  • RelationshipNotDefinedError — $relatedTo references unregistered relationship.
  • InvalidRelationshipPathError — hand-specified path doesn't chain.
  • RelationshipDepthExceededError — graph.path couldn't find a path within depth limit.
  • DuplicateRelationshipError — graph.define saw a name collision.

Constants

  • DEFAULT_TENANT_FIELD = 'tenantId'
  • DEFAULT_MAX_DEPTH = 5
  • RELATED_TO_OPERATOR = '$relatedTo'
  • CROSS_TENANT_MARKER — Symbol-keyed marker on opt-out rules.

nest-warden/typeorm (TypeORM adapter)

Public API

  • accessibleBy(ability, action, subjectType, options) — main entry point. Returns { sql, applyTo(qb) }.
  • buildAccessibleSql(ability, action, subjectType, options) — lower-level SQL fragment builder.
  • TenantAwareRepository<T> — Repository wrapper with auto WHERE injection.
  • TenantSubscriber — TypeORM subscriber for auto-stamping inserts.
  • RlsTransactionInterceptor — NestJS interceptor that opens a transaction and runs set_config(...).

Decorators

  • @TenantColumn() — marker for the tenant-FK column on entities.

Helpers

  • getTenantColumn(target) — read the @TenantColumn metadata.
  • buildRlsSet(tenantId, variableName?) — build the set_config(...) statement.

Constants

  • DEFAULT_RLS_SESSION_VARIABLE = 'app.current_tenant_id'
  • TENANT_COLUMN_METADATA — Symbol-keyed metadata key for @TenantColumn.

nest-warden/nestjs (NestJS adapter)

Module

  • TenantAbilityModule.forRoot<TAbility, TId>(options) — dynamic module entry.

Services

  • TenantContextService<TId> — request-scoped holder for the resolved context.
  • TenantAbilityFactory<TAbility, TId> — request-scoped per-request ability builder.

Guards

  • TenantPoliciesGuard<TAbility> — runs @CheckPolicies(...) handlers.

Interceptors

  • TenantContextInterceptor<TId> — optional explicit hook (the policies guard self-resolves).

Decorators

  • @Public() — bypass auth + tenant resolution.
  • @CheckPolicies(...handlers) — attach policy handlers to a route.
  • @AllowCrossTenant(reasonCode) — mark route as deliberately cross-tenant.
  • @CurrentTenant(field?) — inject the resolved context (or one field) into a controller param.

Types

  • TenantAbilityModuleOptions<TAbility, TId> — forRoot() options shape.
  • PolicyHandler<TAbility> — object form of a policy handler.
  • PolicyHandlerFn<TAbility> — function form.
  • PolicyHandlerLike<TAbility> — union of both.

Tokens

  • MTC_OPTIONS — Symbol-keyed token for the resolved options.
  • IS_PUBLIC_KEY, CHECK_POLICIES_KEY, ALLOW_CROSS_TENANT_KEY — Reflector metadata keys.

TypeScript module resolution

For the subpath exports to resolve, set TypeScript's module resolution to one that respects them:

{
  "compilerOptions": {
    "moduleResolution": "Bundler",
    "// or:": "NodeNext (Node.js 18+)",
    "module": "ESNext"
  }
}

moduleResolution: "Node" (TypeScript's old default) does NOT support package subpath exports — upgrade to Bundler (TS 5.0+) or NodeNext.

See also