Custom filename QWEB report [ODOO 14.0]

I need a big help.

I need to change the report filename when the pdf is downloaded.

This is the button:

<button
   string="Generate Report"
   name="generate_report"
   type="object"
   class="btn-primary"
 />

This is the "generate_report" python function:

def generate_report(self):
        data = {
            'blabla': self.employee_id.name,
            'bla': self.employee_id.place_of_birth
        }

        return self.env.ref('module.action_generate_report').report_action(self, data=data)

And this is the action

<record id="action_generate_report" model="ir.actions.report">
    <field name="name">Generate Report</field>
    <field name="model">custom.module</field>
    <field name="report_type">qweb-pdf</field>
    <field name="report_name">module.generate_report_template</field>
    <field name="report_file">module.generate_report_template</field>
    <field name="print_report_name">"Report - %s" % object.name</field>
    <field name="paperformat_id" ref="paperformat_margin" />
</record>

If i use the "Print" button it works correctly, but if i use the custom button the solution above not work, everytime the file is downloaded, it has the name "Generate Report.pdf"

How to solve this problem?

Thank you

When you define the data parameter, Odoo will not add the active_ids to the report urls:

if (_.isUndefined(action.data) || _.isNull(action.data) ||
   (_.isObject(action.data) && _.isEmpty(action.data))) {
   if (action.context.active_ids) {
       var activeIDsPath = '/' + action.context.active_ids.join(',');
       reportUrls = _.mapObject(reportUrls, function (value) {
           return value += activeIDsPath;
       });
   }
   reportUrls.html += '?context=' + encodeURIComponent(JSON.stringify(session.user_context));
}

and then will fail to get the docids from it in the report_download controller:

pattern = '/report/pdf/' if type == 'qweb-pdf' else '/report/text/'
reportname = url.split(pattern)[1].split('?')[0]

docids = None
if '/' in reportname:
    reportname, docids = reportname.split('/')

which is used to compute the report file name.

If docids is None, Odoo will not compute the report file name from print_report_name expression and will use the report name (report.name)

if docids:
    ids = [int(x) for x in docids.split(",")]
    obj = request.env[report.model].browse(ids)
    if report.print_report_name and not len(obj) > 1:
        report_name = safe_eval(report.print_report_name, {'object': obj, 'time': time})
        filename = "%s.%s" % (report_name, extension)

You don't need to use data parameter, current record fields are accessible throw docs variable. To fix this issue remove the data parameter or set it to None or {}