20 KiB
Refactor Changelog — Input/Output Unification + Presenter + Error Middleware + Public-Surface Cleanup
Started: 2026-05-06 Spec: 2026-05-06-input-output-unification-design.md Plan: 2026-05-06-plan-9-io-unification.md Branch: feature/io-unification
This document captures every architectural change made during Plan 9 execution, organized by category. After the plan is merged, use the "Doc update checklist" at the bottom to update external docs in a single follow-up pass — combined with the still-pending Plan 8 doc-update items so docs are written once for the post-Plan-9 state.
1. Files added
- packages/core-shared/src/trpc/define-error-middleware.ts — middleware factory mapping [ErrorCtor, TRPC_CODE] tuples to TRPCError translation
- packages/core-shared/src/trpc/define-error-middleware.test.ts — 4 tests covering mapped translation, multiple codes, unmapped passthrough (verifies INTERNAL_SERVER_ERROR + cause preservation), cause preservation
- packages/auth/src/integrations/api/procedures.ts — authProcedure with feature error map (InputParse → BAD_REQUEST, Auth/Unauthenticated → UNAUTHORIZED, Unauthorized → FORBIDDEN)
- packages/auth/src/ui/index.ts — placeholder UI surface (no queries today; mutations only)
- packages/blog/src/integrations/api/procedures.ts — blogProcedure with feature error map (InputParseError → BAD_REQUEST, ArticleNotFoundError → NOT_FOUND)
- packages/blog/src/ui/index.ts — re-exports articleBySlugQuery and listArticlesQuery from ./query (moved from feature root index)
- packages/marketing-pages/src/integrations/api/procedures.ts — marketingPagesProcedure with feature error map (InputParseError → BAD_REQUEST, PageNotFoundError → NOT_FOUND)
- packages/marketing-pages/src/ui/index.ts — re-exports pageBySlugQuery and siteSettingsQuery from ./query (moved from feature root index)
- packages/navigation/src/integrations/api/procedures.ts — navigationProcedure with feature error map (InputParseError → BAD_REQUEST, HeaderNotFoundError → NOT_FOUND)
- packages/navigation/src/ui/index.ts — re-exports headerQuery from ./query (moved from feature root index)
2. Files modified
- packages/core-shared/src/trpc/init.ts —
tinstance now exported (was internal const) so feature procedures.ts can dot.procedure.use(...) - packages/core-shared/package.json — added "./trpc/define-error-middleware" subpath export
- packages/core-shared/tsconfig.json — set
rootDir: "."and added@/*path alias so test files using@/resolve correctly undertsc --noEmit - packages/auth/src/application/use-cases/sign-in.use-case.ts — input + output schemas; output.parse before return; SignInInput/SignInOutput types exported
- packages/auth/src/application/use-cases/sign-up.use-case.ts — input + output schemas (with confirmPassword refine); output.parse; types exported; removed user from output (presenter extracts cookie)
- packages/auth/src/application/use-cases/sign-out.use-case.ts — input schema only (void output, no presenter); SignOutInput exported; takes { sessionId } object instead of raw string
- packages/auth/src/interface-adapters/controllers/sign-in.controller.ts — presenter returning cookie; unknown input; ReturnType return type
- packages/auth/src/interface-adapters/controllers/sign-up.controller.ts — presenter returning cookie; unknown input
- packages/auth/src/interface-adapters/controllers/sign-out.controller.ts — no presenter (void); unknown input; Promise return
- packages/auth/src/integrations/api/router.ts — uses authProcedure, .input(xInputSchema)
- packages/auth/src/index.ts — schemas + types now exported from feature root
- packages/auth/package.json — added ./ui subpath
- packages/auth/tests/sign-in-flow.feature.test.ts — updated to match new presenter shapes (cookie return, void sign-out, object input)
- All affected auth use-case + controller tests updated for new contracts
- packages/blog/src/application/use-cases/get-articles.use-case.ts — getArticlesInputSchema + getArticlesOutputSchema; status narrowed to articleStatusSchema; output.parse; types exported
- packages/blog/src/application/use-cases/create-article.use-case.ts — createArticleInputSchema + createArticleOutputSchema; output.parse; types exported
- packages/blog/src/application/use-cases/get-article-by-slug.use-case.ts — getArticleBySlugInputSchema + getArticleBySlugOutputSchema; output.parse; types exported
- packages/blog/src/interface-adapters/controllers/get-articles.controller.ts — identity presenter; unknown input; imports getArticlesInputSchema from use-case
- packages/blog/src/interface-adapters/controllers/create-article.controller.ts — identity presenter; unknown input; imports createArticleInputSchema from use-case
- packages/blog/src/interface-adapters/controllers/get-article-by-slug.controller.ts — identity presenter; unknown input; imports getArticleBySlugInputSchema from use-case
- packages/blog/src/integrations/api/router.ts — uses blogProcedure + .input(xInputSchema) for all 3 procedures
- packages/blog/src/index.ts — removed articleBySlugQuery/listArticlesQuery re-exports; added schemas + types + IUseCase/IController aliases
- packages/blog/package.json — added ./ui subpath export
- All affected blog use-case + controller tests updated for new contracts
- packages/marketing-pages/src/application/use-cases/get-page-by-slug.use-case.ts — getPageBySlugInputSchema + getPageBySlugOutputSchema; output.parse (returns undefined for missing page per existing behavior); types exported
- packages/marketing-pages/src/application/use-cases/get-site-settings.use-case.ts — getSiteSettingsInputSchema (z.object({}).strict() per R5) + getSiteSettingsOutputSchema; output.parse; types exported; _input parameter (void input)
- packages/marketing-pages/src/interface-adapters/controllers/get-page-by-slug.controller.ts — identity presenter; unknown input; returns undefined for missing page
- packages/marketing-pages/src/interface-adapters/controllers/get-site-settings.controller.ts — identity presenter; unknown input; imports getSiteSettingsInputSchema from use-case
- packages/marketing-pages/src/integrations/api/router.ts — uses marketingPagesProcedure + .input(xInputSchema) for both procedures; siteSettings now uses .input(getSiteSettingsInputSchema)
- packages/marketing-pages/src/index.ts — removed pageBySlugQuery/siteSettingsQuery re-exports; added schemas + types + IUseCase/IController aliases
- packages/marketing-pages/package.json — added ./ui subpath export
- All affected marketing-pages use-case + controller tests updated for new contracts
- packages/navigation/src/application/use-cases/get-header.use-case.ts — getHeaderInputSchema (z.object({}).strict()) + getHeaderOutputSchema (= headerSchema); _input parameter; output.parse; types exported
- packages/navigation/src/interface-adapters/controllers/get-header.controller.ts — identity presenter; unknown input; imports getHeaderInputSchema from use-case; ReturnType return type
- packages/navigation/src/integrations/api/router.ts — uses navigationProcedure + .input(getHeaderInputSchema); ctrl called with input
- packages/navigation/src/index.ts — removed headerQuery re-export (moved to ./ui); exports getHeaderInputSchema, getHeaderOutputSchema, GetHeaderInput, GetHeaderOutput, IGetHeaderUseCase, IGetHeaderController; added HeaderNotFoundError + InputParseError re-exports
- packages/navigation/package.json — added ./ui subpath export
- packages/navigation/src/integrations/api/router.test.ts — updated to call caller.header({}); added R26 describe block; uses beforeEach/afterEach to rebind container
3. Pattern changes (code-level)
3.1 Use-case files — input + output schemas + runtime parse
auth migrated: all 3 use cases. signIn and signUp export xInputSchema + xOutputSchema + types; signOut exports xInputSchema only (void output). All non-void use cases end with xOutputSchema.parse(result) before returning.
blog migrated: all 3 use cases. getArticles, createArticle, getArticleBySlug each export xInputSchema + xOutputSchema + XInput + XOutput types. getArticlesInputSchema narrows status to articleStatusSchema (not loose string). All 3 end with xOutputSchema.parse(result) before returning.
marketing-pages migrated: both use cases. getPageBySlug exports getPageBySlugInputSchema + getPageBySlugOutputSchema + types; returns undefined for missing page (preserving existing semantics) — parse only called when page found. getSiteSettings exports getSiteSettingsInputSchema (z.object({}).strict() — void input per R5) + getSiteSettingsOutputSchema + types; takes _input: GetSiteSettingsInput to satisfy uniform input contract.
navigation migrated: single use case (getHeader). Exports getHeaderInputSchema (z.object({}).strict() — void input per R5) + getHeaderOutputSchema (= headerSchema) + types; takes _input: GetHeaderInput; throws HeaderNotFoundError when repository returns falsy (existing behavior preserved); ends with getHeaderOutputSchema.parse(header).
3.2 Controller files — presenter + unknown input + view return type
auth migrated: all 3 controllers. signIn/signUp have function presenter(value: XOutput) returning value.cookie; return type is ReturnType<typeof presenter>. signOut has no presenter (void). All controllers accept unknown input and safeparse with the use-case schema.
blog migrated: all 3 controllers. All 3 (getArticles, createArticle, getArticleBySlug) have function presenter(value: XOutput) that is identity (return value); return type is ReturnType<typeof presenter>. All accept unknown input and safeparse with the imported use-case schema.
marketing-pages migrated: both controllers. getPageBySlug has identity presenter; return type is ReturnType<typeof presenter> | undefined (preserves missing-page semantics). getSiteSettings has identity presenter; return type is ReturnType<typeof presenter>. Both accept unknown input and safeparse with the imported use-case schema.
navigation migrated: single controller (getHeaderController). Identity presenter; return type ReturnType<typeof presenter>. Accepts unknown input and safeparses with getHeaderInputSchema imported from use-case file.
3.3 tRPC integration — feature-scoped procedures, schema reuse from use cases
auth migrated: authProcedure in procedures.ts wraps defineErrorMiddleware with 4-tuple error map. Router uses authProcedure.input(xInputSchema) for all 3 procedures — no more local schema redefinition.
blog migrated: blogProcedure in procedures.ts wraps defineErrorMiddleware with 2-tuple map (InputParseError → BAD_REQUEST, ArticleNotFoundError → NOT_FOUND). Router uses blogProcedure.input(xInputSchema) for all 3 procedures.
marketing-pages migrated: marketingPagesProcedure in procedures.ts wraps defineErrorMiddleware with 2-tuple map (InputParseError → BAD_REQUEST, PageNotFoundError → NOT_FOUND). Router uses marketingPagesProcedure.input(xInputSchema) for both procedures. siteSettings now uses .input(getSiteSettingsInputSchema) (was a no-input .query()).
navigation migrated: navigationProcedure in procedures.ts wraps defineErrorMiddleware with 2-tuple map (InputParseError → BAD_REQUEST, HeaderNotFoundError → NOT_FOUND). Router uses navigationProcedure.input(getHeaderInputSchema) (was a no-input .query() with publicProcedure).
4. Error-middleware adoption
- core-shared infrastructure landed; feature routers will adopt in Tasks 3-7.
- Discriminator:
instanceof Ctor(not error name string), so duck-typing is impossible — features pass their own class constructors. - Cause preservation: TRPCError carries the original domain error in
.causefor client structured-error inspection. - Note on tRPC v11 behavior: unmapped errors still surface as
TRPCError(code: INTERNAL_SERVER_ERROR)because tRPC'screateCallerwraps all procedure errors. Our middleware does not interfere — the original error is preserved as.causefor inspection.
5. Public-API surface
5.1 ./ui subpath added per feature
auth: ./ui subpath added to package.json exports; src/ui/index.ts placeholder created (auth has no query builders — all procedures are mutations).
blog: ./ui subpath added to package.json exports; src/ui/index.ts created re-exporting articleBySlugQuery and listArticlesQuery from ./query.
marketing-pages: ./ui subpath added to package.json exports; src/ui/index.ts created re-exporting pageBySlugQuery and siteSettingsQuery from ./query.
navigation: ./ui subpath added to package.json exports; src/ui/index.ts created re-exporting headerQuery from ./query (moved from feature root index).
5.2 Feature root index.ts cleanup
auth: root src/index.ts now exports all use-case schemas (signInInputSchema, signInOutputSchema, signUpInputSchema, signUpOutputSchema, signOutInputSchema) and types (SignInInput/Output, SignUpInput/Output, SignOutInput, ISignInUseCase, ISignUpUseCase, ISignOutUseCase) plus controller type aliases.
blog: root src/index.ts removed articleBySlugQuery/listArticlesQuery re-exports (moved to ./ui); now exports getArticlesInputSchema/Output, createArticleInputSchema/Output, getArticleBySlugInputSchema/Output, all XInput/XOutput types, IUseCase aliases, and IController aliases.
marketing-pages: root src/index.ts removed pageBySlugQuery/siteSettingsQuery re-exports (moved to ./ui); now exports getPageBySlugInputSchema/Output, getSiteSettingsInputSchema/Output, all XInput/XOutput types, IUseCase aliases, and IController aliases.
navigation: root src/index.ts removed headerQuery re-export (moved to ./ui); now exports getHeaderInputSchema, getHeaderOutputSchema, GetHeaderInput, GetHeaderOutput, IGetHeaderUseCase, IGetHeaderController; also exports HeaderNotFoundError and InputParseError.
6. Test additions
6.1 R25 — output-validation tests (use case)
auth: signIn and signUp each have 2 new R25 tests — one verifying that a malformed service response throws (Zod parse error), one verifying the output schema parses a valid shape. signOut is void — no R25 test.
blog: getArticles, createArticle, getArticleBySlug each have 2 new R25 tests — one verifying that a repository returning a malformed object throws ZodError (instanceof), one verifying the output schema parses a valid shape.
marketing-pages: getPageBySlug has 1 R25 test verifying that a repository returning a malformed page object throws ZodError (instanceof). getSiteSettings has 1 R25 test using an inline malformed repository mock that returns { siteName: "" } (fails min(1) constraint) to assert ZodError (instanceof).
navigation: getHeader has 1 R25 test using an inline malformed repository mock that returns { items: [{ label: "", href: "/", external: false }] } (label fails min(1) constraint) to assert ZodError (instanceof).
6.2 R26 — router error-mapping tests
auth: 2 new R26 tests in router.test.ts — UNAUTHORIZED on missing user (AuthenticationError translation), BAD_REQUEST on Zod schema failure (schema validation at procedure boundary). blog: 2 new R26 tests in router.test.ts — NOT_FOUND on articleBySlug with missing slug (ArticleNotFoundError translation via blogProcedure), BAD_REQUEST on articleBySlug with empty input ({} as { slug: string }) (schema validation at tRPC procedure boundary). marketing-pages: 2 new R26 tests in router.test.ts — BAD_REQUEST on pageBySlug with empty input ({} as { slug: string }) (schema validation at tRPC procedure boundary); undefined return for missing slug confirmed (use case returns undefined rather than throwing PageNotFoundError, so NOT_FOUND mapping does not apply for this use case). navigation: 2 new R26 tests in router.test.ts — BAD_REQUEST on header with extra fields (strict() z.object({}) rejects unknown keys via InputParseError); NOT_FOUND on header when a NullHeaderRepository (inline @injectable class) causes HeaderNotFoundError (container rebound inline for the test).
6.3 R27/R28 — presenter shape tests
- auth (Task 3): sign-in and sign-up controllers reshape
{ session, cookie }→cookie. Controller tests assert cookie shape (result.name,result.value, etc.) — not the full use-case output — proving the presenter ran. Same assertions intests/sign-in-flow.feature.test.ts. sign-out controller has no presenter (void return), so no view-shape test applies.
7. Open issues / deferred decisions
- 2026-05-06 / R6 fix-up (commit
9663c82): Plan 8 left every feature's domain error class with a constructor that did NOT setthis.name. Plan 9 spec R6 explicitly requires it. Caught by spec reviewer during Task 6 (navigation). Fixed across all 10 error files (auth × 4, blog × 2, marketing-pages × 2, navigation × 2, media × 2). Functionally a no-op (defineErrorMiddleware usesinstanceof), but ensures correct serialization, stack-trace labels, and JSON inspectability.
Doc update checklist (deferred — combined with paused Plan 8 doc pass)
After Plan 9 lands, the still-pending Plan 8 doc-update items resume and now also pick up Plan 9 rules. Each item below covers BOTH plans' material so we touch every file once.
CLAUDE.md— Key Conventions: append schema-in-use-case rule, presenter rule, controllerunknowninput rule,./uisubpath rule, schema-export-from-root ruleAGENTS.md(root) — Per-Package Conventions: document./uisubpath, schema reachability from feature root, factory-bound use cases / controllers (carry-over from Plan 8)docs/guides/adding-a-feature.md— restructure to use the Plan-9 use-case template (with input + output schemas + parse), the Plan-9 controller template (with presenter), and the newprocedures.tsstep (per-feature error map)docs/guides/tdd-workflow.md— update mock decision tree + worked example to factory injection (Plan 8) + R25 output-validation test pattern (Plan 9) + R26 router-error-mapping test pattern (Plan 9)docs/guides/testing-strategy.md— Mocking section: direct factory injection (Plan 8); R25/R26/R27/R28 test obligations (Plan 9)docs/architecture/vertical-feature-spec.md— §6 file shape: schemas + presenter + procedures.ts; §10 testing: R25/R26/R27/R28docs/architecture/overview.md— data-flow box: add input schema, output schema, presenter, error-middleware lanesdocs/architecture/dependency-flow.md— verify (no expected change beyond a./uimention)docs/decisions/adr-012-lazar-conformance.md— append note that input/output unification + presenter + error middleware land in ADR-013docs/decisions/adr-013-input-output-unification.md— created in this plan's final task (Task 9); link from prior ADRs- Per-feature
AGENTS.md(auth/blog/media/marketing-pages/navigation) — Plan 8 file paths + Plan 9 schema/presenter/procedures patterns packages/core-testing/AGENTS.md— note R25/R26 test patternspackages/core-shared/AGENTS.md— documentdefineErrorMiddlewareand thetre-export- Plan 8 plan/spec — add a one-line annotation that some controller/router patterns shifted in Plan 9; link to this changelog
Notes for the doc-update pass author
When updating external docs, apply these substitutions globally:
| Old reference | New reference |
|---|---|
Use case takes { x } directly typed |
Use case takes XInput (z.infer<typeof xInputSchema>); schema lives in same file |
Use case returns Promise<Entity> |
Use case returns Promise<XOutput> validated by xOutputSchema.parse(...) |
Controller imports z and defines local inputSchema |
Controller imports xInputSchema from the use-case file |
Controller input typed Partial<z.infer<...>> |
Controller input typed unknown |
Controller returns Promise<Entity> |
Controller has function presenter(value: XOutput); returns Promise<ReturnType<typeof presenter>> (or Promise<void> for void use cases) |
Router uses publicProcedure from core-shared/trpc/init |
Router uses feature's xProcedure from ./procedures |
Router redefines input schema as z.object({...}) in .input(...) |
Router uses .input(xInputSchema) imported from the use-case file |
Domain error reaches the wire as a generic TRPCError({ code: "INTERNAL_SERVER_ERROR" }) |
Domain error mapped to specific code by defineErrorMiddleware in procedures.ts |
Frontend imports articleBySlugQuery from @repo/blog |
Frontend imports from @repo/blog/ui |