Wrapper parity 0.1.1: link buffering, camelCase errors, version

CHANGELOG.md

@@ -1,5 +1,45 @@
 # Changelog
 
+## 0.1.1
+
+Implements [wrapper parity 0.1.1](https://github.com/linktrail-io/workspace/blob/main/contracts/wrapper-parity-0.1.1.md).
+Native SDKs unchanged: iOS `LinkTrailSDK ~> 0.1.0`, Android `io.linktrail:sdk:0.1.0`.
+
+### Changed
+- **Breaking: error codes are now camelCase**, matching the native `LinkTrailError` cases. Every
+  promise rejects with a `LinkTrailError` whose `message` is the native message unchanged; `server`
+  errors also carry `statusCode` and, if present, `body` (also on `onError` events). For this
+  release the old value is still available as `error.legacyCode`; it will be removed in the next
+  minor release.
+
+  | Before (`code`, now `legacyCode`) | After (`code`) |
+  | --- | --- |
+  | `missing_api_key` | `missingApiKey` |
+  | `invalid_api_key` | `invalidApiKey` |
+  | `not_configured` | `notConfigured` |
+  | `invalid_url` | `invalidUrl` |
+  | `not_a_linktrail_url` | `notALinkTrailUrl` |
+  | `empty_response` | `emptyResponse` |
+  | `invalid_argument` | `invalidArgument` |
+  | `transport`, `server`, `decoding`, `unknown` | unchanged |
+
+- **Links and attribution are no longer lost before a listener exists.** The native `onLink` is
+  registered only when the first JS `onLink` listener subscribes, so a deferred link stays saved
+  natively until JS receives it. Re-engagement links resolved earlier are buffered (max 10, oldest
+  dropped) and delivered once, in order, to the first listener. `onAttribution` keeps the last
+  result and replays it to the first listener. Later listeners get no replays. `onLink` /
+  `onAttribution` now return a JS subscription (still `{ remove() }`).
+- **Behavior change (Android):** `requestTrackingAuthorization()` now resolves `true` instead of
+  `false`. Android has no App Tracking Transparency, so the platform never restricts tracking;
+  this matches the Flutter SDK. It is not user consent — keep using `setConsent` /
+  `requireConsent`. iOS is unchanged.
+
+### Added
+- `LinkTrail.version` (this package's version) and `LinkTrail.nativeSdkVersion` (the embedded
+  native SDK's version).
+- `LinkTrailError` class and `LinkTrailErrorCode` type exports.
+- A Jest test suite (`npm test`) covering the JS/TS layer with a mocked native module.
+
 ## 0.1.0
 
 Adopts the native **0.1.0** SDKs: iOS `LinkTrailSDK ~> 0.1.0` (from `0.0.11`) and Android

README.md

@@ -26,7 +26,7 @@ from Maven Central — so there's nothing else to add.
 ## Quick start
 
 ```ts
-import LinkTrail from 'linktrail-react-native';
+import LinkTrail, { LinkTrailError } from 'linktrail-react-native';
 
 // At app launch. The API key is required.
 await LinkTrail.configure('lt_live_…');
@@ -43,6 +43,30 @@ LinkTrail.onError((error) => console.warn(`[LinkTrail] ${error.code}: ${error.me
 The install is tracked automatically by `configure`, and incoming links (Universal Links / App
 Links / custom schemes) are forwarded via React Native's `Linking` API — no extra wiring.
 
+`onLink` can be registered after a splash or login screen: links that arrive before the first
+listener are kept and delivered to it once, in order (later listeners get no replays). A deferred
+link stays saved natively (across launches) until a listener exists; up to 10 re-engagement links
+are buffered in memory. `onAttribution` replays the latest result to its first listener.
+
+### Errors
+
+Every promise rejects with a `LinkTrailError`, and `onError` gets the same fields:
+
+| Field | |
+| --- | --- |
+| `code` | `missingApiKey`, `invalidApiKey`, `notConfigured`, `invalidUrl`, `notALinkTrailUrl`, `transport`, `server`, `decoding`, `emptyResponse`, `invalidArgument`, `unknown` |
+| `message` | The native SDK's message, unchanged |
+| `statusCode`, `body` | `server` errors only (`body` when the server sent one) |
+| `legacyCode` | The pre-0.1.1 snake_case code. Deprecated; removed in the next minor release |
+
+```ts
+try {
+  await LinkTrail.trackEvent('purchase');
+} catch (e) {
+  if (e instanceof LinkTrailError && e.code === 'server') console.warn(e.statusCode, e.body);
+}
+```
+
 ## More
 
 ```ts
@@ -52,8 +76,14 @@ await LinkTrail.trackEvent('purchase', { value: 59.99, currency: 'USD' });
 // Cached results:
 const attribution = await LinkTrail.getLastAttribution();
 const lastLink = await LinkTrail.getLastDeepLink();
+
+// Versions: this package, and the embedded native SDK.
+LinkTrail.version; // "0.1.1"
+LinkTrail.nativeSdkVersion; // e.g. "0.1.0"
 
-// iOS ATT / SKAdNetwork (no-ops on Android):
+// iOS ATT / SKAdNetwork. On Android there is no ATT: requestTrackingAuthorization()
+// is not applicable and resolves `true` (the OS does not restrict tracking); the
+// SKAdNetwork calls are no-ops.
 await LinkTrail.requestTrackingAuthorization();
 LinkTrail.registerForSKAdAttribution();
 LinkTrail.updateConversionValue(42, 'medium');