flotilla/e2e/ARCHITECTURE.md

# E2E architecture

Flotilla's end-to-end suite runs the real app against a relay network that is entirely under the
test's control. Nothing in this directory may ever open a connection to a host the test did not
create. That is the single invariant everything else is arranged around.

## The relay

Every spec runs against a real [zooid](https://github.com/coracle-social/zooid) relay in Docker, the
implementation Flotilla is built for, so protocol drift between the client's assumptions and a real
relay shows up as a failing test.

zooid is multi-tenant: it binds a config to a `Host` header and serves any number of virtual relays
from one process. `harness/zooid/config.ts` names them, one toml apiece in `harness/zooid/docker/`,
and a scenario picks one by name. A second space costs a config file and no extra process, which is
what keeps outbox routing and cross-space isolation testable.

A relay's policy is its toml and nothing else. A scenario says what is _on_ a relay — its rooms, its
members, its messages — never what the relay _is_, so there is no policy negotiation anywhere in the
harness.

### Why the relays are called `<name>.test`

The container listens on plaintext loopback, but a url that is local or insecure is dropped from
every relay selection unless the caller opts in — see `isLocalUrl` and `RelaySelection.getUrls` in
`@welshman/util` — and Flotilla never opts in, since in production neither belongs in a routing
decision. Handed `ws://localhost:3334/`, the client would load a space by its explicit url and
resolve nothing else: no outbox loads for profiles or relay lists, no relay hints.

So the client is given `wss://space.test/` and never learns the container has an address. Everything
that speaks to it goes through `zooid/transport.ts`, which dials `127.0.0.1:3334` carrying the two
headers a TLS terminator adds in front of a real deployment:

- `Host: space.test` — zooid's dispatcher binds a config to a Host (`cmd/relay/main.go`), so this is
  what selects which toml answers.
- `X-Forwarded-Proto: https` — khatru derives the url it checks NIP-42 and NIP-86 signatures against
  from Host plus this (`getBaseURL` in `khatru/relay.go`), arriving at `wss://space.test/`, which is
  exactly what the client signed into its `relay` tag. Seeding signs the same url, so a fixture is
  written over the same relay the app talks to.

`.test` is reserved by RFC 2606 and resolves nowhere, so a url that ever escapes this process fails
to connect rather than reaching a host.

## Transport: one interception point

All relay traffic is intercepted in the **Node** process via Playwright's `routeWebSocket`, applied
to the `BrowserContext` so every page in it is covered:

```
browser context ──▶ context.routeWebSocket(everything but vite's hmr socket)
                          │
                          ▼
                  zooid.relays.get(url)
                          │
        ┌─────────────────┴─────────────────┐
        │                                   │
  a socket this process opens         unknown url: a relay that
  to the container, as that           holds no events, and the
  relay's virtual host                url is recorded as a leak
```

Every socket the browser opens is terminated here, in this process, and the only one that leaves it
is the loopback connection `zooid/transport.ts` makes to the container the test started.
`assertNoLeaks()` fails a test that touched a url the scenario never declared.

Interception is installed by `as()`, on a context it creates, so a page that came from anywhere else
has none of it. Playwright's own `context` fixture — and the `page` fixture built on it — is
therefore overridden to throw, so a spec written the ordinary way fails immediately with a message
saying so rather than quietly dialling the relays in `.env`. The built-in `request` fixture goes the
same way: an `APIRequestContext` is an http client in the node process that belongs to no browser
context, so the block-all below cannot see it and nothing records what it sent.

`playwright` is the one fixture left alone, and it has to be: it is where the run's own browser comes
from, so every test would fail if it threw. A spec that goes around `as()` through
`playwright.request` or `playwright.chromium.launch()` reaches the network unwatched, and no fixture
can refuse that without refusing the suite.

Interception in Node rather than in the page is what makes multi-user testing work. Three browser
contexts logged in as three different users all dispatch into the _same_ relay, so one user
genuinely observes another user's writes, over the wire, through the client's real socket stack.

### Why not an `AdapterFactory`

The obvious alternative — `new App({getAdapter})` returning a `Repository`-backed adapter — cannot
test authentication. NIP-42 lives on `Socket`: `AuthState` listens to `SocketEvent.Receiving`/
`Sending`, and `socketPolicyAuthBuffer` replays messages that were rejected with `auth-required:`.
An `AbstractAdapter` whose `sockets` getter returns `[]` never constructs any of that. Patching the
transport instead leaves `Pool → Socket → SocketAdapter` untouched, so auth, message buffering,
replay-after-auth and reconnect are all exercised as written.

## HTTP

Relays are not the only egress. `installHttpRoutes` routes every url that is not the dev server — a
predicate rather than a `"**/*"` pattern, so the hundreds of module requests a sveltekit page makes
in dev are never even matched — and aborts what it catches. Two origins get past it: the dev server
on `localhost:1847`, which is left unrouted, and each relay's own origin, which is forwarded to the
container by the same transport carrying the same two headers, so the NIP-11 document and the NIP-86
management API the app reads are the real relay's answers, signed against the url the client used.
Every other request is aborted and recorded.

A relay's NIP-11 document decides whether a space is synced by reconciliation or a plain REQ
(NIP-77), whether a message the UI composes carries a protected `-` tag (NIP-70), what the space is
called, and which pubkey room state is trusted from. Its NIP-86 answers decide whether the user is an
admin, since a relay refuses management calls from anyone else and the method list that comes back
doubles as the client's permission set — the space, room, event and pin menus, the directory and the
library are all gated on it.

Services the app talks to are then mocked back in per-scenario, so a blocked request is always a bug
rather than ambient noise: Dufflepud (`dufflepud.coracle.social`), Blossom uploads, the push server
(`nps.flotilla.social`), the hosting API, LiveKit token endpoints, and image/thumbnail fetches. The
analytics script hard-coded in `src/app.html` is mocked with an empty body: it is requested on every
navigation whatever the scenario is doing, so leaving it to the block-all would make
`assertNoBlockedRequests()` a statement about the page shell rather than about the test.

## Containment

A browser has a fixed set of ways to put bytes on a wire.

| how the app can reach the network                                   | what stops it                                                                                                                                                  |
| ------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `WebSocket` — `@welshman/net`'s `Socket`, the only constructor call | `context.routeWebSocket(url => !isDevServerUrl(url))`. Terminated in node; an undeclared url gets a relay holding nothing and `assertNoLeaks()` fails the test |
| `fetch` / `XMLHttpRequest` — app code, welshman, `@pomade/core`     | `context.route(url => !isDevServerUrl(url))`, which aborts unless a mock registered later answers first                                                        |
| `img`, `script`, `link`, fonts, media, and every other subresource  | the same route. Images never reach it — `mockImages` answers anything with `resourceType() === "image"` with a 1×1 png                                         |
| navigation, including the external links the ui offers              | the same route: a document request is routed like any other, and a popup opens in the context that owns it                                                     |
| `EventSource`                                                       | the same route. Neither `src` nor welshman constructs one                                                                                                      |
| `navigator.sendBeacon`                                              | no call site. The one script that would use it is the plausible tag in `src/app.html`, served with an empty body                                               |
| a service worker                                                    | `serviceWorkers: "block"` on the context. Playwright does not route a worker's requests, so the worker is refused instead                                      |
| a web worker                                                        | no call site in `src`; `@pomade/core`'s is argon2, which is cpu and no socket                                                                                  |
| Capacitor's native http and push plugins                            | not reachable from a browser, and the zooid config leaves `[push]` disabled so nothing is asked to register                                                    |

Two connections leave this process, both to something the test started: the browser's to the vite dev
server on `localhost:1847`, and `zooid/transport.ts`'s to `127.0.0.1:3334`. Everything else the app
initiates dies in node.

The two ends are enforced differently. A websocket to a url no scenario declared is answered rather
than refused — by a relay that EOSEs every REQ and accepts every event into the void — and the url is
recorded, so the test fails on `assertNoLeaks()` naming it rather than on a timeout somewhere
downstream. An http request nothing mocked is aborted outright, but noticing it is opt-in:
`assertNoBlockedRequests()` is for a spec that has mocked what it exercises, because some of what a
page asks for is meant to be refused.

Configuration is the other half. `boot()` overrides every `VITE_` value that names a relay — default,
indexer, search, messaging, signer, platform, blocked, the default space list — with the scenario's
own urls, through the hook `src/app/env.ts` reads them with, and points `VITE_PUSH_BRIDGE` at `ws://localhost:1/`, which nothing serves, so a push
bridge connection is reported as a leak rather than blending into a relay's traffic. The `VITE_`
values it does not override still name real hosts — the blossom server, the pomade signers, the
thumbnail service, the push server, the hosting api — and none of them is contacted at boot. Blossom
is read only when an upload starts, the thumbnail url only on android, pomade only when a signup uses
it, and the hosting api and dufflepud are mocked. They are contained by the block-all rather than by
configuration, which is the weaker of the two guarantees.

Grepping the repo for hostnames accounts for all of them, and there are only three kinds. Most are an
`href` in help text — nostr.com, nostrapps.com, nsec.app, nosta.me, nostr.how, github.com,
fountain.fm, cal.com, figma.com, coracle.tools, gitea.coracle.social, nwc.getalby.com, and the
`coracle.social` entity links `src/app/env.ts` builds — reachable only by clicking, and routed if
clicked. Two are fetched: dufflepud, whose origin is the one service url hard-coded rather than read
from `VITE_`, and the plausible tag in `src/app.html`. Both are mocked. The rest are in comments.
Under `e2e` the only hostnames are the four service origins `net/http.ts` matches on, the virtual
relays' own `.test` names, and the loopback address `zooid/transport.ts` dials.

Three things this does not cover:

- **WebRTC.** `livekit-client` opens an `RTCPeerConnection`, and Playwright cannot see one. A voice
  or video room reaches its sfu over ice and dtls with nothing in between. `mockLivekit` decides
  where the client is pointed, which is why its `serverUrl` has to be something the test owns, and
  why `[livekit]` is omitted from the zooid config entirely. A spec that joins a call escapes this
  document's guarantee and needs its own answer.
- **Playwright's own fixtures.** `context`, `page` and `request` are overridden to throw, but
  `playwright` cannot be — it is where the browser comes from. A spec that reaches the network
  through `playwright.request` or `playwright.chromium.launch()` is unwatched.
- **The browser itself.** A browser's own traffic is not the app's and is not routed. Playwright
  launches chromium with `--disable-background-networking`, `--disable-component-update` and
  `--disable-breakpad`, which is the whole of the mitigation, and which is chromium's alone —
  `E2E_BROWSER=firefox` or `webkit` runs the suite under an engine those flags say nothing about.

## Determinism without freezing the clock

Timestamps are never patched. Instead every fixture is generated fresh at the start of each test and
signed with timestamps relative to the moment the test began:

```ts
const scenario = await seed(({relay, user, at}) => {
  const space = relay("space")
  space.room("general", {name: "General"})
  space.join(user.alice, "general")
  space.join(user.bob, "general")
  space.message(user.alice, "general", "morning all", at(2, HOUR))
  space.message(user.bob, "general", "morning!", at(90, MINUTE))
})
```

`at(2, HOUR)` is `now() - int(2, HOUR)` evaluated once per test, so "2 hours ago" renders the same
way on every run without the app's `now()` being touched. Fixtures are published over a real socket,
authenticated as the identity that signed them, so the relay stores exactly what it would have stored
for a real client: there are no pre-signed JSON blobs to drift out of date, and a fixture the relay
would have refused fails the test instead of appearing in a query.

## Users and sessions

Test identities are deterministic secp256k1 keypairs derived from fixed secrets (`alice`, `bob`,
`carol`, `admin`), so a pubkey is stable across runs and can be asserted on directly.

A logged-in user is created by injecting a NIP-01 session before the app boots. `src/app/session.ts`
carries a DEV-only hook: `restoreSession()` prefers `window.__TEST_SESSION__` when it is present, and
`window.__TEST_EVENTS__` becomes the repository contents a returning user's client would have found
on disk. Both branches are stripped from production builds, and injecting through the hook avoids
writing Capacitor's `SecureStorage`/`Preferences` localStorage encoding by hand.

The injected events go in _after_ `storage.ready`. Storage loads what the last session left behind
with `Repository.load`, which clears the repository before inserting, so anything put there while
IndexedDB is still opening is wiped a few milliseconds later — before the layout has rendered
anything, and long before `authPolicy` reads the room list to decide whether to answer a relay's AUTH
challenge.

The cache exists for the harness rather than for the app. In production the client bootstraps itself:
asking a keyed collection for a pubkey loads it, so `authPolicy` reading the user's room and relay
lists to decide whether to answer a challenge is itself what fetches them, as is any outbox-routed
load of the user's own data. Kind-10002 comes back from the public indexers, and `syncRelayList`
cascades into the room list from there.

Here the indexers _are_ the scenario's relays, because `boot()` points every relay list at them, and
those are members-only — so that first load is refused with `auth-required:`, while `authPolicy`,
conservative by default, will not sign for a url no list has named yet. Each waits on the other. The
injected room list breaks the circle, and it is what a user who joined a space through the UI would
have on disk anyway.

The price is that no spec exercises the bootstrap: every one of them starts already knowing which
relays it belongs to, so a regression in the chain from relay list to room list, or in `authPolicy`'s
conservative gate, leaves the suite green. Covering it needs a scenario with a public relay standing
in for an indexer.

Each user is a separate `BrowserContext`, which also gives each one its own IndexedDB and
localStorage, so nothing bleeds between users.

## Layout

```
e2e/
  ARCHITECTURE.md          this document
  harness/
    index.ts               everything a spec imports: `test`, `expect`, helpers
    keys.ts                deterministic keypairs
    zooid/
      config.ts            the virtual relays and their hosts — the one place they are named
      relay.ts             docker lifecycle, reset, seeding over its own authenticated socket
      transport.ts         the only thing that knows the container's address: ws and http to it
      testRelay.ts         the seeding affordances a scenario builds on
      types.ts             TestRelay, RoomOptions, RelayConnection
      docker/
        compose.yaml       no data volume; tmpfs for /app/data and /app/media
        config/            one toml per virtual relay: its host, and its whole policy
    net/
      websocket.ts         routeWebSocket install, dispatch, transcript, leak detection
      http.ts              block-all + per-service mocks
    app/
      boot.ts              env overrides, navigate, wait for mount and for the app to have read
                           the overrides
      session.ts           NIP-01 session injection
    seed/
      scenario.ts          the `seed()` builder and relative-time helpers
      space.ts             one space's fixtures: rooms, members, messages, replies, profiles
  specs/
    *.spec.ts
```

One piece lives outside this directory: `src/lib/test/session.ts` holds the two window keys and the
getters `src/app/session.ts` reads them through. It is the only file the app ships on the harness's
behalf, and `harness/app/session.ts` duplicates the key names rather than importing them, since
importing anything under `src` would pull sveltekit into the node process.

## Resetting between tests

`Zooid.reset()` recreates the container rather than restarting it: with no volume mounted for
`/app/data`, storage lives in the container's writable layer and a tmpfs, so a fresh container is a
fresh database. The configs are bind-mounted read-only and survive, so every test starts against the
same relays with nothing in them. The container is a worker fixture, so the docker start-up cost is
paid once per worker rather than once per test.

Seeding then writes over a real authenticated socket, one per identity per relay, held open for the
rest of the test. A fixture must therefore be signed by one of the identities in `harness/keys.ts`,
since zooid authenticates every write.

## Running

The suite is not run by agents (see CLAUDE.md).

```sh
pnpm exec playwright install                          # once
docker pull gitea.coracle.social/coracle/zooid:latest # once; the harness never pulls
pnpm test                                             # starts and stops the container itself
```

Every test skips when docker is unavailable, rather than failing.

One engine per run rather than a project per engine: these specs exercise sockets, auth and sync, so
a third copy of each buys much less than it costs. `E2E_BROWSER=webkit pnpm test` runs the whole
suite under another one. The container listens on a fixed port and cannot be sharded, which is why
`workers` is 1.

`src/app/env.ts` resolves every `VITE_` value through a DEV-only hook that prefers
`window.__TEST_ENV__`, which `boot()` injects per browser context, so any dev server will do and a
server already listening on `:1847` is reused. `boot()` still checks that the app read the injected
values, and fails naming the hook rather than letting a run drift onto the relays in `.env`.