# Capability Spec Delta: api-auth (api-auth) **Package**: `@suaveplan/api-auth` **Status**: PROPOSED > Every requirement carries a `**Verified by:**` line. ## ADDED Requirements ### Requirement: SessionResolver contract The package SHALL export `SessionResolver` interface: `resolve(req: Request): Promise`, `dispose(): Promise`. A resolver returning `null` means "I don't recognise this request" — NOT "auth failed." Auth failure (401) is the host's decision based on chain outcome + route's `publicRoutes` membership. #### Scenario: every method present - **WHEN** `expectTypeOf()` is checked - **THEN** `resolve` and `dispose` are declared with the documented signatures **Verified by:** `src/resolver/resolver.spec-conformance.test.ts::"SessionResolver declares resolve and dispose"` --- ### Requirement: `import z from "zod"` everywhere Every Zod import MUST use the default form. #### Scenario: no named import of z - **WHEN** the test greps `import z` from `"zod"` - **THEN** zero matches **Verified by:** `tests/zod-import-form.test.ts::"every src file uses default-import z"` --- ### Requirement: Resolver chain — first-match-wins The package SHALL export `SessionResolverChain(resolvers: readonly SessionResolver[]).resolve(req): Promise` running each resolver in order; the first non-null result wins; if all return null, the chain returns null. An empty chain MUST throw `AUTH.CHAIN_EMPTY` at construction. By default, a resolver throwing MUST surface `AUTH.RESOLVER_THREW` AND short-circuit the chain (fail-closed). An opt-in `continueOnThrow: true` flag lets the chain try the next resolver; this is documented as escape-hatch only. #### Scenario: first non-null wins - **WHEN** chain `[null, principalA, principalB]` is run - **THEN** the chain returns `principalA` AND resolver B is NOT called #### Scenario: all null returns null - **WHEN** every resolver returns null - **THEN** the chain returns null #### Scenario: throw is fail-closed by default - **WHEN** resolver A throws AND `continueOnThrow` is false (default) - **THEN** the chain throws `AUTH.RESOLVER_THREW` AND resolver B is NOT called #### Scenario: empty chain rejected at construction - **WHEN** `new SessionResolverChain([])` is called - **THEN** it throws `AUTH.CHAIN_EMPTY` **Verified by:** `src/chain/chain.test.ts::"first non-null wins, later resolvers skipped"` AND `src/chain/chain.test.ts::"all null returns null"` AND `src/chain/chain.test.ts::"throw is fail-closed by default"` AND `src/chain/chain.test.ts::"empty chain rejected at construction"` --- ### Requirement: SecuritySchemeContribution The package SHALL export `SecuritySchemeContribution` with `{ name: string, scheme: OpenApiSecurityScheme }`. Every concrete `SessionResolver` MUST contribute exactly one scheme so `api-openapi` can emit the right `securitySchemes` block. An `AuthAdapter` whose `securityScheme` is absent at registration MUST surface `AUTH.SECURITY_SCHEME_MISSING`. #### Scenario: missing scheme rejected - **WHEN** an `AuthAdapter` without `securityScheme` is registered - **THEN** registration throws `AUTH.SECURITY_SCHEME_MISSING` **Verified by:** `src/security-scheme/security-scheme.test.ts::"registration rejects adapter without securityScheme"` --- ### Requirement: CSRF default policy The package SHALL export `CsrfPolicy.requiresCsrf(scheme: OpenApiSecurityScheme): boolean`. Cookie-based schemes (`type: "apiKey"` AND `in: "cookie"`) default ON; JWT/Bearer schemes (`type: "http"` AND `scheme: "bearer"`) default OFF. Per-route `csrf: false` opt-out is honoured by the host (this package exposes the default; the host applies the override). #### Scenario: cookie scheme defaults to CSRF ON - **WHEN** `requiresCsrf({ type: "apiKey", in: "cookie", ... })` is called - **THEN** the result is `true` #### Scenario: bearer scheme defaults to CSRF OFF - **WHEN** `requiresCsrf({ type: "http", scheme: "bearer" })` is called - **THEN** the result is `false` **Verified by:** `src/csrf-policy/csrf-policy.test.ts::"cookie schemes default to CSRF ON"` AND `src/csrf-policy/csrf-policy.test.ts::"bearer schemes default to CSRF OFF"` --- ### Requirement: CapabilityId augmentation contributes "auth.session" The package SHALL augment the `CapabilityId` union to include `"auth.session"`. #### Scenario: auth.session assignable to CapabilityId - **WHEN** `expectTypeOf<"auth.session">().toMatchTypeOf()` is checked - **THEN** the assertion passes **Verified by:** `src/capability-id/capability-id.spec-conformance.test.ts::"auth.session is a valid CapabilityId after augmentation"` --- ### Requirement: Error codes registry frozen The package SHALL export `AUTH_CODES` containing exactly: `RESOLVER_THREW`, `CHAIN_EMPTY`, `PRINCIPAL_INVALID_SHAPE`, `SECURITY_SCHEME_MISSING`. #### Scenario: every code reachable - **WHEN** the test enumerates `AUTH_CODES` - **THEN** every code has a production throw site **Verified by:** `src/error-codes/error-codes.spec-conformance.test.ts::"every AUTH_CODES entry thrown by production path"` --- ### Requirement: Conformance harness for resolvers The package SHALL export `runAuthSessionConformance({ factory, label })`. Every concrete resolver in Stages 4/6/8 MUST pass it. #### Scenario: harness covers resolve null, resolve principal, dispose - **WHEN** the harness is run against a stub resolver - **THEN** test categories exist for each documented behavior **Verified by:** `src/testing/conformance.test.ts::"harness covers resolve null, resolve principal, dispose lifecycle"`