Generate multiple PDF report in Django Views For loop

Question

In my Django application, in a Batch, there are multiple Inquiries. Each Inquiry has a related Candidate. A candidate has multiple Addresses. I want to generate a PDF that will include all Candidates and their related Addresses. I am using Weasyprint to generate the PDF.

Models.py

class Batch(models.Model):
    batch = models.CharField(verbose_name='Reference Number', max_length=200)

class Candidate(models.Model):
    name = models.CharField(help_text='', max_length=200)
    nationality = models.CharField(max_length=200)

class Address(models.Model):
    DEFAULT_COUNTRY_ID = 1
    PERA= 'Permanant Address'
    PREA= 'Present Address'

    ADDRESS_TYPE_CHOICES = [
        (PERA, 'Permanant Address'),
        (PREA, 'Present Address'),
    ]
    candidate = models.ForeignKey(Candidate, on_delete=models.CASCADE, verbose_name='Candidate')
   nid = models.CharField(verbose_name='NID', max_length = 15, unique = True, null=True, blank=False)
    address_type = models.CharField(max_length=200, choices=ADDRESS_TYPE_CHOICES)
    address_line_1 = models.CharField('Address Line 1', max_length=1000,  null=True, blank=True)
    state = models.ForeignKey(State, on_delete=models.CASCADE,)
    city = models.ForeignKey(City, on_delete=models.CASCADE,)
    country = models.ForeignKey(Country, on_delete=models.CASCADE, default=DEFAULT_COUNTRY_ID)

class Inquiry(models.Model):
    batch = models.ForeignKey(Batch, on_delete=models.CASCADE, null=True,)
    candidate = models.ForeignKey(Candidate, on_delete=models.SET_NULL, null=True, blank=True)
    name = models.CharField(verbose_name='Name', help_text='', max_length=200)
    nid = models.CharField(verbose_name='NID', max_length = 15, null=True, blank=False)

Here is what I tried. But it just generates multiple instances of the first Candidate. How can I generate a PDF with all Candidates and their relevant Addresses?

views.py

def download_batch_report(request, pk):
    inquiries = Inquiry.objects.filter(batch=pk)
    batch = get_object_or_404(Batch, id=pk)
    for inquiry in inquiries:
        inquiry = get_object_or_404(Inquiry, id=inquiry.id)
        candidate = get_object_or_404(Candidate, nid=inquiry.nid)
        addresses = Address.objects.filter(candidate=candidate)
        print_time = timezone.now()
        font_config = FontConfiguration()
        context = {'batch': batch, 'inquiries': inquiries, 'inquiry': inquiry, 'candidate': candidate,'addresses': addresses, 'print_time': print_time}
        html_string = render_to_string('ssvr/batch/report.html', context).encode(encoding="UTF-8")
        css = CSS(string='''
        @font-face {
            font-family: kalpurush;
            src: url(file:///mnt/d/djangoprojects/dj-boot-modal/librarydb/static/librarydb/fonts/kalpurush.ttf);

        }''', font_config=font_config)
        response = HttpResponse(content_type='application/pdf')

        response['Content-Disposition'] = 'inline; filename='+str(batch.batch)+'_'+str(timezone.now())+'.pdf'
        
        HTML(string=html_string).write_pdf(response, stylesheets=[css], presentational_hints=True, font_config=font_config)
        return response

report.html

<!DOCTYPE html>
<html lang="en">
{% load static %}
{% load tz %}

<head>
    <meta charset="UTF-16">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>{{ batch.batch }}</title>
</head>

<body>
    {% for inquiry in inquiries %}
    <div id="content" class="border_sx">
        <div class="profile">
            <div class="row">
                1. Full Name: {{ candidate.name }} <br>
                2. Nationality: {{ candidate.nationality }} <br>
                <hr>
            </div>
            <div class="row">
                {% for address in addresses %}
                    {% if address.address_type == 'Permanant Address' %}
                        3. Permanant Address: {{ address.address_line_1 }}, {{ address.city }}, {{ address.state }}, {{ address.country }} 
                    {% endif %}
                {% endfor %} <br>
                {% for address in addresses %}
                    {% if address.address_type == 'Present Address' %}
                    4. Present Address: {{ address.address_line_1 }}, {{ address.city }}, {{ address.state }}, {{ address.country }} 
                    {% endif %}
                {% endfor %}
            </div> <br>
            <hr>
            <br>
        <div>
        <div>
            <p>
                Report Generated at:
                {% localtime on %}
                {{ print_time|timezone:"Asia/Dhaka" }}
                {% endlocaltime %}
            </p>
        </div>
    </div>
    <div class="break"></div>
    {% endfor %}
</body>
</html>

score 1 · Accepted Answer · answered Mar 02 '22 at 23:14

There is no need to pass Candidate object in the context. Use inquiry.candidate to access the candidate attached to each inquiry. Same for addresses. Use inquiry.candidate.address_set.all to loop through those.

Also, there is no need for the for loop in your view since you're doing it in the report. In any case, on the first run of the loop, the code will reach return and exit the function.

Generate multiple PDF report in Django Views For loop

1 Answers1