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An order is placed at the time of a valid purchase from the end-user. This is for a product to be made available to the customer in all services. The bookstore calls this on behalf of the customer. If id is specified for an order id, the order is attached to this and can’t be changed. There are some variations in the data you need to send in depending on what type of DRM the book.
Place an order
The get inventory service can give data on your entire catalogue or detailed information on one specific tittle.
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The returned location header points to the bought resource, for details on how to access the content see Get contentContent download.