I am creating a site for student registrations with the django framework.
I have arrived at a place where I have to display the form to the user and I receive the information entered after treatment I have to send an email to the user user containing the information he has entered by putting them in a PDF which I must generate from a template containing the context dictionary.
For the moment the PDF that I can generate is possible only by sending it to the browser through the function HttpResponse, but the problem with that is that it is the user who decides to download it or not and I have more possibility to put the hand on the pdf to send it as an attachment.
I thought to open a database where there will be a field of type models.FileField, generate the pdf with the context dictionary through the library xhtml2pdf that I could save in the database with a signal and then send the email by taking the file as attachment.
None of the methods I tried to achieve this are successful for the moment. Here is my code:
from io import BytesIO
from django.http import HttpResponse
from django.template.loader import get_template
from xhtml2pdf import pisa
def render_to_pdf(template_src, context_dict={}):
template = get_template(template_src)
html = template.render(context_dict)
result = BytesIO()
pdf = pisa.pisaDocument(BytesIO(html.encode("ISO-8859-1")), result)
if not pdf.err:
return HttpResponse(result.getvalue(), content_type="application/pdf")
return None
from django.conf import settings
from django.db.models.signals import pre_save, post_save
from django.core.mail import EmailMessage, EmailMultiAlternatives
from django.db import models
# Create your models here.
class MyModel(models.Model):
order_id = models.CharField(max_length=255)
nom = models.CharField(max_length=255)
email = models.EmailField()
pdf = models.FileField(upload_to="pdfs", null=True, blank=True)
def create_order_id(instance, new_order_id=None):
order_id = instance.id
if new_order_id is not None:
order_id = new_order_id
qs = MyModel.objects.filter(order_id=order_id)
exists = qs.exists()
if exists:
new_order_id = "%s-%s" %(order_id.first().id)
return create_order_id(instance, new_order_id)
return order_id
def pre_save_receiver(sender, instance, *args, **kwargs):
if not instance.order_id :
instance.new_order_id = create_order_id(instance)
def send_mail_insciption(instance):
subject = "Thank you"
from_email = settings.EMAIL_HOST_USER
to_email = [instance.email]
body = "Votre inscription"
email_pdf = EmailMultiAlternatives(
subject = subject,
body =body,
from_email = from_email,
to=to_email,
)
email_pdf.attach_alternative(instance.pdf, "application/pdf")
email_pdf.send()
def post_save_receiver(sender, instance, *args, **kwargs):
send_mail_insciption(instance)
pre_save.connect(pre_save_receiver, sender=MyModel )
post_save.connect(post_save_receiver, sender=MyModel)
#views.py
def pdf_genarete(request):
form = MyModelForm(request.POST or None)
if form.is_valid():
nom = form.cleaned_data.get("nom")
email = form.cleaned_data.get("email")
obj = MyModel.objects.create(nom=nom, email=email)
context = {"models_instance": obj}
pdf = render_to_pdf("pdfapp/template_pdf.html", context)
filename = "mypdf_{}.pdf".format(obj.order_id)
pdf.save()
obj.pdf.save(filename, File(BytesIO(pdf.content)))
return redirect(reverse("home"))
return render(request, "pdfapp/formulaire.html", {"form": form})
After execution here is the error on the terminal:
File "/home/michel/saintexupery/env/lib/python3.6/site-packages/django/db/models/base.py", line 769, in save_base
update_fields=update_fields, raw=raw, using=using,
File "/home/michel/saintexupery/env/lib/python3.6/site-packages/django/dispatch/dispatcher.py", line 178, in send
for receiver in self._live_receivers(sender)
File "/home/michel/saintexupery/env/lib/python3.6/site-packages/django/dispatch/dispatcher.py", line 178, in <listcomp>
for receiver in self._live_receivers(sender)
File "/home/michel/saintexupery/saintexupry/pdfapp/models.py", line 69, in post_save_receiver
send_mail_insciption(instance)
File "/home/michel/saintexupery/saintexupry/pdfapp/models.py", line 65, in send_mail_insciption
email_pdf.send()
File "/home/michel/saintexupery/env/lib/python3.6/site-packages/django/core/mail/message.py", line 294, in send
return self.get_connection(fail_silently).send_messages([self])
File "/home/michel/saintexupery/env/lib/python3.6/site-packages/django/core/mail/backends/smtp.py", line 110, in send_messages
sent = self._send(message)
File "/home/michel/saintexupery/env/lib/python3.6/site-packages/django/core/mail/backends/smtp.py", line 124, in _send
message = email_message.message()
File "/home/michel/saintexupery/env/lib/python3.6/site-packages/django/core/mail/message.py", line 254, in message
msg = self._create_message(msg)
File "/home/michel/saintexupery/env/lib/python3.6/site-packages/django/core/mail/message.py", line 440, in _create_message
return self._create_attachments(self._create_alternatives(msg))
File "/home/michel/saintexupery/env/lib/python3.6/site-packages/django/core/mail/message.py", line 450, in _create_alternatives
msg.attach(self._create_mime_attachment(*alternative))
File "/home/michel/saintexupery/env/lib/python3.6/site-packages/django/core/mail/message.py", line 393, in _create_mime_attachment
Encoders.encode_base64(attachment)
File "/usr/lib/python3.6/email/encoders.py", line 32, in encode_base64
encdata = str(_bencode(orig), 'ascii')
File "/home/michel/saintexupery/env/lib/python3.6/base64.py", line 534, in encodebytes
_input_type_check(s)
File "/home/michel/saintexupery/env/lib/python3.6/base64.py", line 520, in _input_type_check
raise TypeError(msg) from err
TypeError: expected bytes-like object, not FieldFile
I your code you have this part:
def send_mail_insciption(instance):
...
email_pdf.attach_alternative(instance.pdf, "application/pdf")
email_pdf.send()
The error message (and traceback) say that the email expects bytes as attachment, but instance.pdf is a FieldFile.
Try converting the file to bytes, maybe using instance.pdf.read() and let us know if that solves the problem.