docs/link/INTEGRATION.md

# uo-link Sidecar — Website Integration Guide

This is the API the website talks to. The sidecar is the only thing the site connects to; it relays to and from the ServUO shard over a private loopback socket. The game itself exposes no ports and is never reachable directly.

```
website ──WebSocket (live feed) + REST (queries/commands)──►  sidecar  ──loopback──►  shard
```

- **Base URL** — default `http://127.0.0.1:8080` (WebSocket: `ws://127.0.0.1:8080`). Configurable in `sidecar.toml` (`web.bind`) or `UOLINK_WEB_BIND`. If you serve the site from another host, bind the sidecar to `0.0.0.0:8080` and put it behind TLS.
- **Content type** — all request and response bodies are JSON (`application/json`).
- **Timestamps** — every `t` field is **epoch milliseconds** (UTC). Human-readable timestamps (e.g. `house.decay.builtOn`, `/health.last_event`) are ISO-8601 UTC.
- **Serials** — game object ids are hex strings like `"0x24C"` (mobiles) or `"0x40013AAD"` (items). Treat them as opaque keys.

---

## 1. Authentication

Every route **except `GET /health`** requires the shared token from `sidecar.toml` (`web.auth_token`). Present it any of these ways:

| Transport | How |
|-----------|-----|
| REST | `Authorization: Bearer <token>` |
| REST | `X-Api-Key: <token>` |
| WebSocket | `?token=<token>` in the connect URL (browsers can't set headers on a WS handshake) |

Missing or wrong token → **401** `{"error":"missing or invalid auth token"}`. The token is compared in constant time. It is generated automatically on first run (the sidecar logs it); rotate by editing `sidecar.toml` and restarting.

---

## 2. Protocol version

The wire protocol is versioned so a mismatch is caught immediately instead of failing weirdly.

- Every response carries an **`X-UOLink-Version: 1`** header.
- `GET /health` and the WebSocket `ws.hello` frame include `"protocol": 1`.
- **Optionally**, send `X-UOLink-Version: 1` on your requests. If it disagrees with the sidecar, the request is rejected **409 Conflict**:

  ```json
  { "error": "protocol version mismatch", "sidecar_protocol": 1, "client_protocol": "2" }
  ```

Pin the version you built against and compare it to the header (or `/health.protocol`) at startup.

---

## 3. Health

```
GET /health          (no auth)
```

```json
{
  "status": "ok",                      // "ok" when plugin connected AND db reachable, else "degraded"
  "protocol": 1,
  "plugin_connected": true,            // is the shard link up right now?
  "database": "ok",                    // "ok" | "error"
  "uptime": "3d 12h",
  "last_event": "2026-07-10T22:08:27Z" // last line received from the shard; null if none yet
}
```

Always returns HTTP 200 (read `status`/`plugin_connected` for real state). Use it for liveness checks and to detect when the shard has dropped (`plugin_connected: false`).

---

## 4. WebSocket live feed

```
GET /ws?token=<token>        (WebSocket upgrade)
```

A push-only stream of game events as they happen. You do **not** send commands over the WebSocket — use REST for that. The socket carries one JSON object per text frame.

**On connect**, the first frame is:

```json
{ "kind": "ws.hello", "protocol": 1 }
```

**Then** a continuous stream of event frames, each with at least `t` (epoch ms) and `kind`. Route on `kind`.

Notes:
- **Live-only, no replay.** A client that connects now sees events from now on. For history/backfill, use `GET /history`.
- The sidecar sends WebSocket **ping** frames every ~30s for keepalive; browser clients answer automatically.
- You may occasionally see a `{"kind":"pong",...}` frame (the sidecar's internal heartbeat to the shard). Ignore any `kind` you don't handle.
- A client that falls far behind is dropped rather than allowed to stall others — reconnect and backfill via REST if that happens.

### Minimal browser client

```js
const ws = new WebSocket(`ws://127.0.0.1:8080/ws?token=${TOKEN}`);
ws.onmessage = (m) => {
  const ev = JSON.parse(m.data);
  switch (ev.kind) {
    case "ws.hello":      /* check ev.protocol === 1 */ break;
    case "mob.login":     onLogin(ev); break;
    case "vendor.sale":   onSale(ev); break;
    case "house.decay":   onIdoc(ev); break;
    // ...handle the kinds you care about; ignore the rest
  }
};
ws.onclose = () => setTimeout(connect, 2000); // reconnect + backfill via /history
```

### Event catalog

Every event has `t` (epoch ms) and `kind`. A nested actor object looks like `{"serial","name","acct","player"}` (`acct` present only for player-owned mobiles).

#### Lifecycle
| kind | fields | notes |
|------|--------|-------|
| `server.hello` | `shard`, `bootId`, `connects`, `items`, `mobiles`, `accounts` | Sent to the sidecar on every shard (re)connect. `bootId` changes on a shard restart; stable across sidecar reconnects — use it to tell "shard restarted" (drop caches) from "sidecar reconnected". |
| `server.shutdown` | — | Clean shutdown. |
| `server.crashed` | `error` | Not always sent (a hard crash may skip it). |
| `world.save.before` / `world.save.after` | (`after` adds `items`, `mobiles`) | Save-cycle boundaries; a natural consistency checkpoint. |

#### Sessions & identity
| kind | fields |
|------|--------|
| `mob.login` | `who`, `map`, `x`, `y`, `z`, `webId` (present if the account is linked) |
| `mob.logout` | `who` |
| `account.login.attempt` | `acct`, `ip` — an authentication attempt (no password ever leaves the shard) |

#### Economy & commerce
| kind | fields | notes |
|------|--------|-------|
| `gold.change` | `acct`, `old`, `new`, `delta` | AccountGold flow (gold in bank/account, not physical coins). |
| `vendor.buy` | `who`, `vendor`, `item`, `itemSerial`, `amount`, `perUnit`, `total`, `committed:false` | **NPC** vendor purchase (validation stage). |
| `vendor.sell` | `who`, `vendor`, `item`, `itemSerial`, `amount`, `perUnit`, `total`, `committed:false` | **NPC** vendor sale. |
| `vendor.sale` | `buyerSerial`, `buyerAcct`, `ownerSerial`, `ownerAcct`, `vendorSerial`, `itemType`, `itemSerial`, `itemId`, `amount`, `price`, `commission`, `committed:true` | **Player** vendor sale, at the committed transaction. Carries both buyer and owner accounts — the pair that flags laundering when they match. |
| `vendor.placed` | `owner`, `vendor` | A player vendor was placed. |

```json
{"kind":"vendor.sale","committed":true,"buyerAcct":"wttest","buyerSerial":"0x2E0",
 "ownerAcct":"seed_000","ownerSerial":"0x1F5","vendorSerial":"0x2E1",
 "itemType":"Longsword","itemSerial":"0x40015218","itemId":3937,"amount":1,
 "price":100,"commission":0,"t":1783720195626}
```

#### Character progression & vitals
| kind | fields | notes |
|------|--------|-------|
| `char.vitals` | `serial`, `hits`,`hitsMax`, `mana`,`manaMax`, `stam`,`stamMax`, `str`,`dex`,`int`, `map`, `x`,`y` | Periodic snapshot of each **online** player (~every 30s; configurable). Diff successive snapshots to detect change. |
| `skill.gain` | `who`, `skill`, `gained`, `base`, `cap` | Player skill gains only (NPC gains are filtered out). |
| `fame.change` / `karma.change` | `who`, `old`, `new` | Player only. |
| `quest.complete` | `who`, `quest` | |

#### Death & PvP
| kind | fields |
|------|--------|
| `player.death` | `who`, `killer` |
| `player.murdered` | `victim`, `murderer` |
| `mob.killed` | `killed`, `killer` — only kills that involve a player |

#### Housing / IDOC
| kind | fields |
|------|--------|
| `house.decay` | `serial`, `from`, `to`, `map`, `x`,`y`,`z`, `region`, `name`, `ownerSerial`, `ownerAcct`, `ban:{x,y,z}`, `builtOn`, `lastRefreshed` |

`from`/`to` are decay stages (`LikeNew`, `Slightly`, `Somewhat`, `Fairly`, `Greatly`, `IDOC`, `Collapsed`, …). Emitted only on a **transition**, so watch for `to == "IDOC"`. `ban` is where a player would stand to see the sign.

```json
{"kind":"house.decay","serial":"0x4004705F","from":"Somewhat","to":"Fairly",
 "map":"Trammel","x":1119,"y":1794,"z":0,"region":null,"name":"An Unnamed House",
 "ownerSerial":"0x75","ban":{"x":1112,"y":1804,"z":0},
 "builtOn":"2026-05-11T03:12:24Z","lastRefreshed":"2026-05-31T02:36:51Z"}
```

#### Economy supply (periodic)
| kind | fields |
|------|--------|
| `economy.supply` | `accounts`, `gold` — total money supply across all accounts (~every 5 min; configurable) |

#### Cheat detection & staff audit
| kind | fields | notes |
|------|--------|-------|
| `cheat.fastwalk` | `who`, `ip` | The shard's own speed-hack detector fired. |
| `audit.set` | `staff`, `prop`, `target`, `targetSerial`, `old`, `new` | A staff member used `[set` to change a property. `staff` may be null. |
| `audit.command` | `staff`, `command`, `args` | A staff command was invoked. |

#### Account linking
| kind | fields | notes |
|------|--------|-------|
| `link.request` | `code`, `account`, `char`, `ttlSec` | A player ran `[link` in game. Show them a prompt to enter `code` on the site; you then confirm it via `POST /link/confirm`. See §6. |

---

## 5. REST — read queries

These fetch live state from the shard (correlated round-trip). Typical latency is a few milliseconds; the sidecar waits up to 10s for the shard before returning **504**.

### Character profile

```
GET /char/{account}/{slot}          # by account + character slot (0-based)
GET /char/serial/{serial}           # by serial, e.g. /char/serial/0x24C
```

Full character sheet: stats, all trained skills, worn equipment with flattened item mods. Works for **offline** characters too. `GET /char/serial/...` falls back to the last **cached** profile if the shard is unreachable (so a page still renders during a shard restart).

```json
{
  "kind": "char.profile", "serial": "0x24C", "name": "Darrow", "title": null,
  "body": 400, "hue": 33770, "online": false, "acct": "whitlocktech",
  "stats": { "str":120,"dex":120,"int":123, "hits":110,"hitsMax":110,
             "mana":123,"manaMax":123, "stam":120,"stamMax":120,
             "fame":0,"karma":0,"luck":0,
             "resist": {"phys":44,"fire":44,"cold":44,"pois":44,"energy":44} },
  "skills": [ {"n":"Swords","base":120.0,"value":120.0,"cap":120.0,"lock":"Up"}, "..." ],
  "equipment": [
    { "serial":"0x40013AAD","layer":"Shirt","itemId":7933,"hue":33,
      "cliloc":1027933,"mods":{} },
    { "serial":"0x4002B3","layer":"OneHanded","itemId":5046,"hue":0,"cliloc":1023721,
      "weapon":{"minDamage":16,"maxDamage":18},
      "mods":{"WeaponDamage":50,"HitLightning":40} }
  ]
}
```

Field notes:
- `skills[].base` is trained value, `value` includes item/temp bonuses, `cap` is the cap. **Do not assume `base <= cap`** — GM characters can exceed it.
- `equipment[].mods` is a flattened map of every non-zero AOS attribute on the item (weapon or armor). Empty `{}` for plain items.
- Item names are usually **clilocs**, not strings: use `name` when present, otherwise resolve `cliloc` against a UO cliloc table on the site.
- Errors: unknown account → **404** `{"kind":"bridge.error","reason":"unknown account"}`; bad slot → **404**/**400** similarly.

### Account roster

```
GET /roster/{account}
```

Lightweight list of an account's characters (up to 5–7), including offline ones. Use this for a character-picker, then fetch the full profile on demand.

```json
{ "kind":"account.roster", "acct":"whitlocktech",
  "chars":[ {"slot":0,"serial":"0x24C","name":"Darrow","body":400,"online":false} ] }
```

### Player vendors

```
GET /vendors/{account}
```

Every player vendor owned by any character on the account, with held gold and current listings.

```json
{ "kind":"vendor.snapshot", "acct":"seed_000",
  "vendors":[
    { "serial":"0x2C0", "shopName":"Seed Shop 810", "holdGold":24186,
      "ownerSerial":"0x1F5", "map":"Felucca", "x":1402, "y":1604,
      "listings":[
        {"serial":"0x4001440F","itemId":3937,"amount":1,"price":69819,"forSale":true}
      ] } ] }
```

---

## 6. REST — commands & history

### Confirm an account link

The in-game `[link` flow: the player runs `[link`, the shard emits a `link.request` event (over the WebSocket) carrying a one-time `code`. Your site shows the logged-in website user a box to enter that code, then:

```
POST /link/confirm
{ "code": "AB12CD", "websiteUserId": "9931" }
```

- Success → **200** `{"kind":"link.ok","code":"AB12CD","account":"PerryAdimn","websiteUserId":"9931"}`. The game account is now permanently tagged with your `websiteUserId` (persisted on the shard); subsequent `mob.login` events for that account carry `webId`.
- Bad/expired code → **404** `{"kind":"link.error","code":"AB12CD","reason":"unknown or expired code"}`.

Codes are one-time and expire (default 5 min).

### Look up an existing link

```
GET /link/{account}
```

- **200** `{"account":"PerryAdimn","websiteUserId":"9931"}` if linked.
- **404** `{"account":"PerryAdimn","linked":false}` if not.

(This reads the sidecar's mirror of confirmed links — no shard round-trip.)

### Publish / remove town-crier news

Push a message that every in-game town crier announces until it expires.

```
POST /towncrier
{ "id": "news-42", "lines": ["Hear ye!", "Market tax is now 5%."], "durationSec": 3600 }
```
→ **200** `{"kind":"towncrier.ok","id":"news-42"}`. Re-posting the same `id` replaces the prior entry.

```
DELETE /towncrier/{id}
```
→ **200** `{"kind":"towncrier.ok","id":"news-42"}`, or **404** `{"kind":"towncrier.error","reason":"unknown id"}`.

Caps apply (line count/length, active entries, duration); an over-cap post returns `towncrier.error`.

### History (from the sidecar's database)

```
GET /history?kind={kind}&limit={n}     # kind optional, limit default 100 (max 1000)
GET /economy?limit={n}                 # the money-supply series (economy.supply events)
```

Recent events, **newest first**, served from SQLite (no shard needed). This is your backfill when a WebSocket client (re)connects, and the source for feeds like "recent sales" or "latest IDOC".

```
GET /history?kind=vendor.sale&limit=50
→ { "events": [ {"kind":"vendor.sale", "...": "...", "t": 1783720195626}, ... ] }

GET /economy?limit=200
→ { "series": [ {"kind":"economy.supply","accounts":52,"gold":110502898,"t":...}, ... ] }
```

---

## 7. Status codes

| Code | Meaning |
|------|---------|
| 200 | OK |
| 400 | Bad request (malformed body, invalid parameter, or a shard `*.error` that isn't a not-found) |
| 401 | Missing or invalid auth token |
| 404 | Not found (unknown account / character / id) |
| 409 | Protocol version mismatch (you sent `X-UOLink-Version` and it disagreed) |
| 500 | Internal error (e.g. database) |
| 503 | Shard not connected — the query needs the live game and it's down |
| 504 | Shard connected but didn't reply within 10s |

`503` vs `404`: a `503` is transient (shard restarting — retry), a `404` is a real "doesn't exist."

---

## 8. Putting it together

A typical character page:

```js
const H = { "Authorization": `Bearer ${TOKEN}`, "X-UOLink-Version": "1" };

// 1. render the roster
const roster = await fetch(`${BASE}/roster/${account}`, { headers: H }).then(r => r.json());

// 2. full sheet for the selected character
const res = await fetch(`${BASE}/char/${account}/${slot}`, { headers: H });
if (res.status === 503) showBanner("Game server is restarting…");
else renderProfile(await res.json());

// 3. live vitals: subscribe to the feed and update hp/mana as char.vitals arrives
//    (see the WebSocket client in §4)

// 4. recent sales widget
const sales = await fetch(`${BASE}/history?kind=vendor.sale&limit=20`, { headers: H })
  .then(r => r.json());
```

---

## 9. Caveats & current limits

- **No rate limiting yet.** The sidecar does not throttle callers; put it behind your own gateway if it's public. Profile/roster/vendor queries hit the live shard, so cache them site-side.
- **WebSocket is push-only and live-only.** No client→server messages, no replay. Backfill via `/history`.
- **Cache freshness.** `GET /char/serial/...` may serve a stale cached profile when the shard is down; the account+slot form always goes live (503 if down).
- **`bootId`** on `server.hello` is your signal to invalidate site-side caches: if it changed, the shard restarted.
- **Protocol changes** bump `X-UOLink-Version`. Compare it on startup and fail fast rather than mis-parsing a newer shape.