Insert a purchase invoice, which will then be converted into a book entry. The result will contain the generated book entry's id.

There are two ways to insert an invoice, either with or without an attached document.

• When no document is attached, use the application/json content type as usual.
• For joining a document to the invoice, use the multipart/form-data content type and add two arguments. The first one must be named file and contain the file's bytes, and the other one must be named body and contain the json-formatted information.

The total amount must be equal to the sum of the base amount and tax amount. Additionnally, the sum of each line's base amount must be equal to the global base amount (same for the tax amount).

The accepted tax combinations (Tax type / kind / rate / origin / condition / condition value)) are available here.