Mail template multi attachment

This module extends the standard email templates in Odoo so that a single template can produce more than one attachment.

On the email template form you get a new "Attachments" tab. It keeps the usual single report fields under "Simple attachment" and adds a "Multi attachments" list where you can add as many report lines as you want. Each line lets you pick a report and, optionally, give it a custom file name; the report list is filtered to reports that match the model of the template.

When the email is generated, the module renders every report listed in that multi-attachment list for each recipient and adds the resulting files to the email attachments. PDF and HTML reports are supported; other report types raise a user error. If no custom file name is given, the report's own print name is used, and the correct file extension is added automatically.

Access rights are provided for system users and regular users (regular users cannot delete attachment lines). The module touches the mail.template model and adds a new mail.template.report model used to store each report line.