# Advanced ## Manual exposure The PHP server is stateless and **never auto-logs** experiment exposures. To get exposure parity with the browser, call `logExposure()` on the bound `Client` at the point you actually present the treatment: ```php use Shipeasy\Client; $client = new Client($currentUser); // construct once per callsite $r = $client->getExperiment('checkout_button', ['color' => 'blue']); $client->logExposure('checkout_button'); // emits one exposure if enrolled ``` It re-evaluates the experiment for the bound user; if enrolled, it POSTs a single `exposure` event to `/collect`. No-op in test/offline mode or when the user isn't enrolled. ## Private attributes Attribute names listed in `privateAttributes` are **stripped from outbound event payloads** (`track()` / exposures). The server evaluates locally, so targeting still works — only the transmitted properties are scrubbed. ```php use function Shipeasy\configure; configure($_ENV['SHIPEASY_SERVER_KEY'], null, [ 'privateAttributes' => ['email', 'phone'], ]); ``` ## bucketBy (custom bucketing unit) The bucketing unit is **server-configured per experiment** — set `bucketBy` on the experiment in the dashboard and the SDK reads it from the blob, bucketing on that attribute (e.g. `company_id`) instead of the user id. Make sure that attribute is present on the user you bind, via the `attributes` transform or the user object itself: ```php use function Shipeasy\configure; use Shipeasy\Client; configure($_ENV['SHIPEASY_SERVER_KEY'], fn ($u) => [ 'user_id' => $u->id, 'company_id' => $u->companyId, // present so bucketBy: company_id works ]); $client = new Client($currentUser); // construct once per callsite $r = $client->getExperiment('pricing_test', $default); ``` ## Sticky bucketing Pass a `Shipeasy\StickyBucketStore` to keep a user in the same variant across re-randomizations. The interface is a durable get/set over a cookie / Redis / database: ```php interface StickyBucketStore { public function get(string $unit): ?array; public function set(string $unit, string $exp, array $entry): void; } ``` Wire it through `configure()`: ```php use function Shipeasy\configure; configure($_ENV['SHIPEASY_SERVER_KEY'], null, [ 'stickyStore' => new MyRedisStickyStore(), ]); ``` `Shipeasy\InMemoryStickyStore` is a built-in non-durable implementation useful in a single long-running process or tests. ## Anonymous-visitor bucketing For logged-out traffic you need a *stable* unit so a fractional rollout buckets the same on the server and in the browser. Call `Identity::ensure()` once early in your bootstrap (before any output) — it reads or mints the shared `__se_anon_id` first-party cookie used by every Shipeasy SDK: ```php use Shipeasy\{Client, Identity}; Identity::ensure(); // read or mint __se_anon_id (+ Set-Cookie) $client = new Client([]); // construct once per callsite $client->getFlag('new_checkout'); // buckets on the cookie automatically ``` An explicit `user_id` / `anonymous_id` always wins. Works in plain PHP, WordPress, Laravel, Symfony, Slim — anywhere `$_COOKIE` / `setcookie()` exist (call it from middleware / a service provider in a framework). The cookie is non-`HttpOnly` by design so the browser SDK buckets identically; a request with **no** unit still resolves a fully-rolled (100%) gate as on. ## Offline snapshots Evaluate the **real** rules against a baked blob instead of the network (air-gapped / edge hosts, reproducible CI) with `Shipeasy\configureForOffline()`. See [Testing](testing.md) for the full snapshot JSON shape. ```php use function Shipeasy\configureForOffline; use Shipeasy\Client; // From a JSON file: { "flags": , "experiments": } configureForOffline(['path' => '/etc/shipeasy/snapshot.json']); // Or from already-decoded blobs: configureForOffline(['snapshot' => ['flags' => $flagsBody, 'experiments' => $expBody]]); (new Client(['user_id' => 'u1']))->getFlag('new_checkout'); // evaluated, no network ``` ## Change listeners `Shipeasy\onChange()` registers a callback fired whenever the SDK refreshes with a **new** server response (a 200, never a 304), returning an unsubscribe callable: ```php use function Shipeasy\onChange; $unsub = onChange(function () { // re-read flags here; the blob just changed }); $unsub(); // stop listening ``` > **PHP runtime caveat.** This SDK runs no background poll thread. Under classic > **PHP-FPM the SDK is rebuilt per request**, so a listener will not fire on its > own — change listeners are mainly relevant to **long-running runtimes** > (Swoole, RoadRunner, queue/CLI workers) that keep the SDK alive and refresh the > blob on a schedule. Each listener is wrapped in `try/catch`, so a throwing > listener never breaks a refresh; listeners never fire in test/snapshot mode. ## SSR bootstrap See [i18n](i18n.md) for `Shipeasy\bootstrapScriptTag()` / `Shipeasy\i18nScriptTag()` and wiring the browser SDK from the server-rendered ``.