Starts Subbly.js with your Storefront API key and resolves with the SDK instance. Every other method in this reference is a method of that instance. `init` always loads the shop first, so `subbly.shop` is filled in by the time the promise resolves. It then checks the stored access token, and, when you pass `loadCart`, loads or creates a cart and copies the cart currency onto the instance. A failed shop load rejects the promise. Call `init` once per page. The SDK builds one shared HTTP client and keeps it, so a second call with a different `apiKey`, `apiUrl` or `lang` quietly reuses the first one. How to start the SDK. Leave it out, or pass an empty `apiKey`, and `init` rejects with `Error('Missing required apiKey config')`. Your Storefront API key. The SDK sends it as the `x-api-key` header on every request, and you get it from [Shop settings](https://subbly.co/admin/settings/api-keys) in Subbly Admin. Base URL of the Storefront API. Defaults to `https://api.subbly.co/storefront/v1/`. Change it only for a proxy or a test environment. An empty string falls back to the default. Language code, sent as the `accept-language` header. Empty by default, so the server picks. Use a code from `subbly.shop.languages[].code`, and change it later with `subbly.setLanguage`. Cart to load at start-up. The SDK reads it only when `loadCart` is true, and falls back to the `subbly_cart_id` cookie when you leave it out. Load or create a cart during start-up. `false` by default. When it is true, the SDK loads the cart named by `cartId` or the cookie, creates a new cart when there is none or the load fails, writes the `subbly_cart_id` cookie, and calls `subbly.setCurrency` with the cart currency. When it is false, `subbly.cart` has no `id` and the cart methods that need one fail. Customer access token to verify at start-up. It beats the `subbly_access_token` cookie, and the SDK writes it to that cookie when the check passes. A failed check clears the cookie; it does not reject. The SDK instance. Version of the SDK package. The `apiKey`, `apiUrl` and `lang` the SDK started with. The cart: every field of the cart object, plus the cart methods. The [Cart](/reference/subbly-sdk/cart) page writes the fields out. The shop: every field of the shop object, plus `shop.load`. The [Shop](/reference/subbly-sdk/shop) page writes the fields out. The rest of the namespaces, one per group in this reference. They are all built during `init` and are always present. ```js title="Start the SDK" import Subbly from '@subbly/sdk' const subbly = await Subbly.init({ apiKey: 'API_KEY', }) ``` ```js title="Start with a cart and a customer" const subbly = await Subbly.init({ apiKey: 'API_KEY', cartId: 'aaea067c-6364-4157-82e9-71b6edfd84a0', loadCart: true, accessToken: 'eyJh...eyJ9', }) ``` Sets the currency for the prices in later product, bundle and survey responses. The SDK sends it as the `x-currency` header. It only fans the code out to `subbly.products.setCurrency`, `subbly.bundles.setCurrency` and `subbly.surveys.setCurrency`, which each store it for their own requests; an `x-currency` header you pass on a single call still wins. This does not change the cart currency. Use `subbly.cart.update({ currencyCode })` for that. When `init` loads a cart, it calls `setCurrency` with the cart currency itself. A currency abbreviation the shop supports, such as `USD`. Read the list from `subbly.shop.currencies[].abbreviation`. Nothing. ```js title="Set the currency" subbly.setCurrency('EUR') // Later product prices come back in euros. const products = await subbly.products.list() ``` Sets the `accept-language` header the SDK sends with every later request. A language code the shop supports. Read the list from `subbly.shop.languages[].code`. Nothing. ```js title="Set the language" subbly.setLanguage('fr') ``` A read-only property with the version of the `@subbly/sdk` package the page loaded. Useful in a bug report. The version of the `@subbly/sdk` package on the page. ```js title="Read the version" console.log(subbly.VERSION) ``` The three client values `init` received, exactly as you passed them. It leaves out `cartId`, `loadCart` and `accessToken`, and it does not follow a later `setLanguage` call. `subbly.config` is not the configuration in use. The SDK applies its defaults deeper in, when it builds the HTTP client, so a value you left out stays `undefined` here. The values passed to `init`. The Storefront API key you passed. The base URL you passed, or `undefined`. The requests still go to `https://api.subbly.co/storefront/v1/` in that case. The language code you passed, or `undefined`. The server then picks the language. ```js title="Read the configuration" const subbly = await Subbly.init({ apiKey: 'API_KEY' }) subbly.config.apiKey // 'API_KEY' subbly.config.apiUrl // undefined subbly.config.lang // undefined ```