docs: bring README in line with strict mode, routing, and the HTTP boundary
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Updates the architecture/dependency diagrams and omissions table to match
what actually shipped: RemoteData<T> (not <E, T>), @angular/router moved
from "avoided" to "used", the new shared/infrastructure/http.ts fetch
boundary, and the CI/coverage gates now in place. Removes the now-false
"CI pipeline" omission row and adds honest rows for the linter and
per-environment config this template still deliberately skips.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
This commit is contained in:
eho
2026-08-01 10:30:02 +02:00
co-authored by Claude Sonnet 5
parent c895929f58
commit 7dddf875a2
2 changed files with 64 additions and 42 deletions
+52 -28
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@@ -3,8 +3,8 @@
A minimal Angular 22 starter: signals for state, `resource()` for async data, and a
`RemoteData` type that makes "loading but has an error," "success with no value," and
similar illegal combinations impossible to construct. One worked feature (`users/`) shows
the whole pattern end to end, including an action (click a user → see their details →
go back).
the whole pattern end to end, including a routed, deep-linkable action (click a user →
see their details at `/users/:id`go back).
It's extracted from a larger reference app — the "POC" referenced throughout this
document — which shows the same ideas grown up to production scale (multi-context DDD,
@@ -17,6 +17,9 @@ exactly where to reach for the rest as a project grows.
```bash
npm start # ng serve
npm test # ng test (Vitest)
npm run test:coverage # ng test --coverage, gated by thresholds in angular.json
npm run format:check # prettier --check .
npm run build # production build
```
## Architecture
@@ -31,12 +34,13 @@ Growth path.
flowchart TD
subgraph shared["shared/ (cross-context)"]
sapp["application/\nremote-data.ts"]
sinfra["infrastructure/\nhttp.ts (the only fetch() caller)"]
sui["ui/\natoms → molecules → templates"]
end
subgraph users["users/ (one context)"]
udom["domain/\nuser.ts (no Angular import)"]
uinfra["infrastructure/\nusers.adapter.ts (the only fetch() caller)"]
uinfra["infrastructure/\nusers.adapter.ts (parses + type-guards)"]
uapp["application/\n*.resource.ts"]
uui["ui/\norganisms + page"]
end
@@ -44,6 +48,7 @@ flowchart TD
uui --> uapp
uapp --> udom
uapp --> uinfra
uinfra -. uses .-> sinfra
uui -. reuses .-> sui
uapp -. reuses .-> sapp
@@ -53,9 +58,10 @@ flowchart TD
### Why so few dependencies
The whole app runs on `@angular/core`'s signals + `resource()` and native `fetch`
nothing else is imported directly, even though a couple of these are installed
transitively (by `@angular/forms`/`@angular/router`) or available and simply unused.
The whole app runs on `@angular/core`'s signals + `resource()`, native `fetch`, and
`@angular/router` for navigation — nothing else is imported directly. `rxjs` is a peer
dependency of `@angular/core` itself and is never imported by this template's own code.
`@angular/forms` has been dropped entirely — nothing here used it.
```mermaid
flowchart LR
@@ -63,36 +69,44 @@ flowchart LR
app -->|imports| core["@angular/core\nsignal · computed · resource"]
app -->|calls| fetchApi["native fetch()"]
app -->|navigates via| router["@angular/router"]
app -.->|"installed transitively,\nnever imported directly"| rxjs["rxjs"]
app -.->|"installed,\nnever used — signal swap instead"| router["@angular/router"]
app -.->|"peer dep of @angular/core,\nnever imported directly"| rxjs["rxjs"]
app -.->|"never installed —\nzoneless by default"| zonejs["zone.js"]
app -.->|"never installed"| ngrx["NgRx / any store lib"]
app -.->|"never installed —\nfetch() instead"| http["HttpClient"]
classDef used fill:#dfe,stroke:#4a4
classDef avoided fill:#fee,stroke:#a44,stroke-dasharray: 4 4
class core,fetchApi used
class rxjs,router,zonejs,ngrx,http avoided
class core,fetchApi,router used
class rxjs,zonejs,ngrx,http avoided
```
## What's here
- **`RemoteData<E, T>`** (`shared/application/remote-data.ts`) — a 4-variant union
- **`RemoteData<T>`** (`shared/application/remote-data.ts`) — a 4-variant union
(`Loading | Empty | Failure | Success`) plus `fromResource()`, which projects Angular's
own `resource()` into one. No store, no reducer — `resource()` already holds the async
state; `RemoteData` just normalizes it for exhaustive rendering.
own `resource()` into one. `Failure` carries the real `Error` — no generic error
parameter to instantiate, since Angular's `resource()` only ever fails with an `Error`.
No store, no reducer — `resource()` already holds the async state; `RemoteData` just
normalizes it for exhaustive rendering.
- **`<app-async>`** (`shared/ui/molecules/async.component.ts`) — a `@switch` over all 4
states: a spinner while loading, an empty message, a failure message with a retry
button, or your projected content on success. Reused by both fetches in `users/`.
button, or your projected content on success. Because `<ng-content>` can't hand data
back to its parent, pages narrow the same `RemoteData` value themselves with `@let`
before rendering their payload — see `users.page.ts` for the pattern. Reused by both
fetches in `users/`.
- **`<app-page-shell>`** (`shared/ui/templates/page-shell.component.ts`) — a heading plus
one content slot. That's it.
- **`users/`** — one feature context, laid out the same way a bigger one would be:
`domain/` (pure types, no Angular import), `infrastructure/` (the only file allowed to
call `fetch`), `application/` (composes infrastructure + `resource()` — this is also
exactly where a real store would slot in later), `ui/` (organisms + the page). Clicking
a user in the list sets one plain `signal` on the page, which swaps in a
`UserDetailComponent` that does its own independent fetch:
`domain/` (pure types, no Angular import), `infrastructure/` (parses and type-guards
the raw API response into `User`/`UserDetail`, throwing a typed `HttpError` or
`ParseError` on failure — `shared/infrastructure/http.ts` is the only file that calls
`fetch` directly), `application/` (composes infrastructure + `resource()` this is
also exactly where a real store would slot in later), `ui/` (organisms + the page).
Routing is wired with `withComponentInputBinding()`, so clicking a user navigates to
`/users/:id` and the route param binds straight onto the page's `userId` input — no
manual signal wiring, and the detail view is deep-linkable:
```mermaid
sequenceDiagram
@@ -102,6 +116,7 @@ flowchart LR
participant RD as fromResource()
participant Async as app-async
participant List as app-user-list
participant Router as Router
Page->>Res: usersResource()
Res->>Api: loader()
@@ -109,27 +124,35 @@ flowchart LR
Page->>RD: fromResource(usersResource, isEmptyUserList)
RD-->>Async: RemoteData tag (Loading/Empty/Failure/Success)
Async->>List: render on Success
List->>Page: select.emit(id)
Page->>Page: selectedUserId.set(id)
List->>Router: select.emit(id) → navigate(['/users', id])
Router->>Page: binds userId input from the route
Note over Page: template swaps to app-user-detail,<br/>which repeats the same chain via userDetailResource
```
- Path aliases `@shared/*` and `@users/*` (see `tsconfig.json`) instead of relative
`../../` imports, one per context — add one per new context you create.
- Tests are BDD-style (`describe`/`it`, one `expect` per `it`) and black-box: they assert
on rendered DOM and emitted events, never on a component's private fields, so a test
never breaks just because an internal was refactored.
never breaks just because an internal was refactored. Routed pages are tested with
`RouterTestingHarness` driving real navigation (see `users.page.spec.ts`), not by
poking at signals directly.
- **Type safety & CI** — `strict` and `strictTemplates` are both on, so `RemoteData`'s
"illegal states unrepresentable" claim is actually checked by the compiler, not just a
convention. `.github/workflows/ci.yml` runs a format check, the test suite (with
coverage thresholds), and a production build on every push and pull request.
## What's deliberately not here (vs. the POC)
| Missing | Why |
| ------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------- |
| ---------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| Elm-style store (`createStore`/Model-Msg-reduce) | Not needed until a page's state has more than a couple of interacting fields — see Growth path below. |
| i18n (`$localize` + translation file) | POC-specific requirement (a Dutch app shipping English too); irrelevant for a single-locale starter. |
| CIBG Huisstijl theming / token bridge | The POC's specific design system; a starter has no house style to vendor yet. |
| `dependency-cruiser` boundary enforcement | Real value once you have 2+ contexts that must not import each other; overhead for one. |
| `contracts/` layer + generated API client + `parse*` boundary | Only earns its keep once you're consuming a real backend's OpenAPI contract, not a public test API. |
| `contracts/` layer + generated API client | A hand-written `parse*` boundary already guards the response shape (see `users/infrastructure/users.adapter.ts`); only add codegen once there's a real OpenAPI contract to generate from, not a public test API. |
| Linter (`ESLint`/`angular-eslint`) | `strict` + `strictTemplates` + Prettier already catch most of what a linter would here; add one when you have team-specific rules — it's five more devDependencies and a config most teams rewrite anyway. |
| Per-environment config (`.env` / `fileReplacements`) | The API base URL is a single exported `const` in `shared/infrastructure/http.ts` — greppable, zero ceremony. Swap for Angular's built-in `fileReplacements` + `src/environments/` when you need per-deploy values. |
| Storybook + axe a11y gate | Testing/documentation infrastructure that pays off at a much bigger component count. |
| CI pipeline | Nothing to gate yet with one context and no deploy target. |
## Growth path — when you outgrow this
@@ -146,9 +169,10 @@ not before:
infrastructure`/`ui` direction this template already follows by convention but doesn't
check.
- **You're consuming a real backend's OpenAPI contract** → add a `contracts/` layer
(wire DTOs) + a generated typed client + a hand-written `parse*` boundary in
`infrastructure/` (see ADR-0001, `.claude/skills/bff-endpoint/SKILL.md` if you're
working from the POC directly).
(wire DTOs) + a generated typed client on top of the hand-written `parse*` boundary
already in `infrastructure/` (see `users/infrastructure/users.adapter.ts`, and
ADR-0001 / `.claude/skills/bff-endpoint/SKILL.md` if you're working from the POC
directly).
- **A second locale** → wrap user-facing copy in `$localize` with a stable custom id and
add a translation `.xlf` file (see the POC's `CLAUDE.md` "User-facing copy" convention).
- **A real design system** → vendor your CSS, then bridge your own token names onto it the
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@@ -34,7 +34,7 @@ flowchart LR
Three plain ingredients, no framework required:
- **State** — a plain object describing what's true right now. Example: `{ count: 0 }`.
- **A message** — a plain object describing *what happened*. Example:
- **A message** — a plain object describing _what happened_. Example:
`{ type: 'increment' }`. (Some call this an "action" — same thing.)
- **A pure update function** — a function that takes the current state and a message,
and returns the **new** state. "Pure" just means: same inputs always give the same
@@ -122,9 +122,7 @@ export type UsersModel = {
recentlyViewed: number[];
};
export type UsersMsg =
| { type: 'select'; id: number }
| { type: 'closeDetail' };
export type UsersMsg = { type: 'select'; id: number } | { type: 'closeDetail' };
export const initialUsersModel: UsersModel = {
selectedUserId: null,
@@ -145,7 +143,7 @@ export function reduceUsers(model: UsersModel, msg: UsersMsg): UsersModel {
```
This is the point where a single `signal<number | null>` stopped being enough:
`recentlyViewed` is a second field that changes *together* with `selectedUserId`, and
`recentlyViewed` is a second field that changes _together_ with `selectedUserId`, and
`reduce` is the one place that keeps them in sync.
## 5. Using it from a component
@@ -189,7 +187,7 @@ consistent.
## 6. Async actions — the store doesn't replace `resource()`
Keep these concerns separate: `resource()` still owns *fetching*; the store only owns
Keep these concerns separate: `resource()` still owns _fetching_; the store only owns
synchronous state that's derived from, or reacts to, what's fetched. Don't move `fetch`
calls into `reduce``reduce` must stay pure (no side effects), so a network call has no
business being inside one.