Add a row to a qweb odoo report - report

Question

I have a qweb report in which I want to add a line that contain the total of every cols of the report:
this is my qweb code; its about creating a payroll report, its contain 11 cols, I want to add a row of totals by cols
<data>
<t t-call="report.html_container">
<t t-foreach="docs" t-as="o">
<t t-call="report.external_layout">
<div class="page" >
<br></br><br></br>
<div class="row" style="border: 1px solid black">
<div class="col-md-12 text-center"><h2>JOURNAL DE PAIE</h2></div>
<div class="col-md-12 text-center"><p>Période du <span t-esc="data['form']['date_start']"/> au <span t-esc="data['form']['date_end']"/></p></div>
</div>
<br></br><br></br>
<div class="row">
<table class="table table-striped table-bordered table-condensed table-hover" >
<thead><!-- table head-->
<tr style="background-color: #BEC5C0;">
<th>Periode</th>
<th>Matricule</th>
<th>Employé</th>
<th>BASE</th>
<th>Primes</th>
<th>BRUT</th>
<th>CNSS</th>
<th>SAL IMPO</th>
<th>IRPP</th>
<th>Avance/pret</th>
<th>NET A PAYER</th>
</tr>
</thead>
<tbody>
<tr t-foreach="get_all_payslip_per_period(data['form']['date_start'],data['form']['date_end'])" t-as="p" >
<td style="text-align:center;" t-esc="get_month_name(p.date_from)"></td>
<td t-esc="p.employee_id.id"></td>
<td t-esc="p.employee_id.name"></td>
<t t-foreach="get_payslip_lines(p.line_ids)" t-as="l">
<t t-if="l.code=='BASE'">
<t t-set="base" t-value="l.total"/>
<td t-esc="base"></td>
</t>
</t>
<!-- primes -->
<td>
<div t-foreach="get_primes_values(p)" t-as="pr" >
<div style="text-align:left;background-color: #BEC5C0;" t-esc="pr['code']"></div>
<div style="text-align:right;background-color:#CDD8D0;" t-esc="pr['val']"></div>
</div>
</td>
<t t-foreach="get_payslip_lines(p.line_ids)" t-as="l">
<t t-if="l.code=='BRUT' ">
<t t-set="brut" t-value="l.total"/>
<td t-esc="brut"></td>
</t>
<t t-if="l.code=='CNSS' ">
<t t-set="cnss" t-value="l.total"/>
<td t-esc="cnss"></td>
</t>
<t t-if="l.code=='NET' ">
<t t-set="net" t-value="l.total"/>
<td t-esc="net"></td>
</t>
<t t-if="l.code=='IRPP' ">
<t t-set="irpp" t-value="l.total"/>
<td t-esc="irpp"></td>
</t>
</t>
<td t-esc="p.avance_amount"></td>
<td t-esc="get_total_by_rule_category(p, 'AUTRE')-get_total_by_rule_category(p, 'RCC')-(p.avance_amount)"></td>
</tr>
</tbody>
</table>
</div>
</div>
</t>
</t>
</t>
</data>

Answer 1

Try this:
<t t-set="brut" t-value="0"/> <!-- initialize the variable-->
<t t-foreach="get_payslip_lines(p.line_ids)" t-as="l">
<t t-if="l.code=='BRUT' ">
<t t-set="brut" t-value="brut + l.total"/>
</t>
</t>
<td t-esc="brut"></td> <!-- To show it on the report-->
Initialize you variables before:
<tr t-foreach="get_all_payslip_per_period(data['form']['date_start'],data['form']['date_end'])" t-as="p" >
And sum before adding the new tr containing the totals:
</tr>
<tr>
<td><t t-esc='Total1'/></td>
...
</tr>
</tbody>