Dynamically generate PDF and email it using django

Question

I have a django app that dynamically generates a PDF (using reportlab + pypdf) from user input on an HTML form, and returns the HTTP response with an application/pdf MIMEType.

I want to have the option between doing the above, or emailing the generated pdf, but I cannot figure out how to use the EmailMessage class's attach(filename=None, content=None, mimetype=None) method. The documentation doesn't give much of a description of what kind of object content is supposed to be. I've tried a file object and the above application/pdf HTTP response.

I currently have a workaround where my view saves a pdf to disk, and then I attach the resulting file to an outgoing email using the attach_file() method. This seems wrong to me, and I'm pretty sure there is a better way.

Answer 1

Ok I've figured it out.

The second argument in attach() expects a string. I just used a file object's read() method to generate what it was looking for:

from django.core.mail import EmailMessage

message = EmailMessage('Hello', 'Body goes here', 'from@example.com',
    ['to1@example.com', 'to2@example.com'], ['bcc@example.com'],
    headers = {'Reply-To': 'another@example.com'})
attachment = open('myfile.pdf', 'rb')
message.attach('myfile.pdf',attachment.read(),'application/pdf')

I ended up using a tempfile instead, but the concept is the same as an ordinary file object.

Answer 2

Generate the file temp.

from django.utils import timezone    
from io import BytesIO
from reportlab.pdfgen import canvas
from reportlab.lib.pagesizes import letter

def generate_pdf(pk):
    y = 700
    buffer = BytesIO()
    p = canvas.Canvas(buffer, pagesize=letter)
    p.setFont('Helvetica', 10)
    p.drawString(220, y, "PDF generate at "+timezone.now().strftime('%Y-%b-%d'))
    p.showPage()
    p.save()
    pdf = buffer.getvalue()
    buffer.close()
    return pdf

Attach the PDF to message

from django.core.mail import EmailMessage
def send(request)
    pdf = generate_pdf(pk)
    msg = EmailMessage("title", "content", to=["email@gmail.com"])
    msg.attach('my_pdf.pdf', pdf, 'application/pdf')
    msg.content_subtype = "html"
    msg.send()

Answer 3

Based on the example in your link:

message.attach('design.png', img_data, 'image/png')

Wouldn't your content for a pdf just be the same output that you would normally write to the pdf file? Instead of saving the generated_pdf_data to myfile.pdf, plug it into the content field of the message.attach:

message.attach('myfile.pdf', generated_pdf_data, 'application/pdf')