PHP

These use PHP’s built-in curl extension - no Composer dependencies required.

A small client

<?php

const BASE_URL = "https://dev-api.theprioryshop.co.uk";
$apiKey = getenv("EPOS_API_KEY"); // never hardcode this

class EposApiException extends Exception {
    public string $code;
    public string $requestId;
    public function __construct(string $code, string $requestId, string $message) {
        parent::__construct($message);
        $this->code = $code;
        $this->requestId = $requestId;
    }
}

function epos_get(string $path, array $query = []): array {
    global $apiKey;
    $url = BASE_URL . $path . (count($query) ? "?" . http_build_query($query) : "");
    $ch = curl_init($url);
    curl_setopt($ch, CURLOPT_HTTPHEADER, ["Authorization: Bearer $apiKey"]);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    $raw = curl_exec($ch);
    $status = curl_getinfo($ch, CURLINFO_HTTP_CODE);
    curl_close($ch);

    $body = json_decode($raw, true);
    if ($status >= 400) {
        $error = $body["error"];
        throw new EposApiException($error["code"], $error["requestId"], $error["message"]);
    }
    return $body;
}

List products

$products = epos_get("/v1/catalog/products", ["pageSize" => 20]);
echo $products["total"] . " products total, " . count($products["rows"]) . " on this page\n";

Get a single product

$product = epos_get("/v1/catalog/products/clx1product000001");

List categories, promotions, inventory stock

$categories = epos_get("/v1/catalog/categories");
$promotions = epos_get("/v1/catalog/promotions");
$stock = epos_get("/v1/inventory/stock", ["storeId" => "clx1store0000001"]);

Handle an error

try {
    epos_get("/v1/catalog/products/does-not-exist");
} catch (EposApiException $err) {
    if ($err->code === "not_found") {
        echo "No such product\n";
    } elseif ($err->code === "rate_limited") {
        echo "Back off and retry - see Rate Limits\n";
    } else {
        echo "EPOS API error {$err->code} (request {$err->requestId})\n";
    }
}

Paginate through every product

function all_products(): Generator {
    $page = 1;
    while (true) {
        $result = epos_get("/v1/catalog/products", ["pageSize" => 100, "page" => $page]);
        foreach ($result["rows"] as $row) {
            yield $row;
        }
        if ($page >= $result["totalPages"]) {
            break;
        }
        $page += 1;
    }
}

foreach (all_products() as $product) {
    // ...
}

Incremental sync with updatedSince

$since = $lastSyncedAt->format("Y-m-d\TH:i:s.v\Z");
$changed = epos_get("/v1/catalog/products", ["updatedSince" => $since]);

See Catalog Sync for the full pattern.