You can integrate Google Checkout with your custom order processing system using one of the following APIs:
In most cases, merchants who use the XML API to integrate Google Checkout with their custom shopping cart will also use the XML API to integrate Google Checkout with their custom order processing system. Similarly, most merchants who use the HTML API to integrate Google Checkout with their custom shopping cart will also use the HTML API to integrate Google Checkout with their custom order processing system. However, it is possible to use one integration method for integration with a custom shopping cart and the other integration method for integration with a custom order processing system.
Note: The Google Checkout client libraries and sample code leverage the XML API. Using the client libraries should reduce the time needed to integrate.
Features - HTML API enables merchants to send information to and receive information from Google Checkout servers using name/value pairs in HTTP POST requests.
Technical skills required - The programmer responsible for integrating your custom order processing system with Google Checkout via the API should have a strong working knowledge of:
Recommendation - HTML implementations are recommended for merchants whose custom shopping carts are integrated with Google Checkout using the HTML API or for merchants who are more comfortable parsing or constructing name-value pairs than XML. The HTML API has no client libraries or sample code.
Features - XML API enables merchants to send information to and receive information from Google Checkout using XML that constitutes the body of an HTTP request. Client libraries and sample code that leverage the XML API are available for you to generate carts and receive notifications.
Technical skills required: - The programmer responsible for integrating your custom order processing system with Google Checkout via the API should have a strong working knowledge of:
Recommendation - XML implementations are recommended for merchants whose custom shopping carts are integrated with Google Checkout using the XML API or for merchants who are more comfortable parsing or constructing XML than name-value pairs. The XML API is also recommended for merchants who wish to take advantage of the available client libraries and sample code.