Where to hook in request = context['request']?

[jhagege]

Hi guys,

I've been playing around with your package and making progress with it.

I am now stuck with a particular issue: I am using another third-party package that needs access to the context['request'] when trying to render the absolute url path of elements that I put inside the template (such as in {% absolute_url 'functionfoo' %} but for some reason I get an error thrown when trying to access the context['request'] inside this template tag.

It looks like the HtmlEmail class doesn't pass the request object inside the context. What would be the best way to go to include it? I guess I would have somehow to pass the context whenever creating an HTMLEmail().

Thanks a lot for your help.

[rockymeza]

You could do something like this:

from emailtools import HTMLEmail

class ThingCreatedAdminEmail(HTMLEmail):
    template_name = 'things/mail/thing_created_admin.html'
    subject = "New Thing Created"

    def __init__(self, thing, request):
        self.thing = thing
        self.request = request

    def get_to(self):
        return [user.email for user in User.objects.filter(is_superuser=True)]

    def get_context_data(self, **kwargs):
        kwargs = super(ThingCreatedAdminEmail, self).get_context_data(**kwargs)
        kwargs.update(
            thing=self.thing,
            request=self.request,
        )
        return kwargs

Then when you want to send your emails, you can do so like this:

def view(request):
    # ...
    email = ThingCreatedAdminEmail(thing, request=request)
    email.send()
    # ...

Another thing you can do is use the BuildAbsoluteURIMixin mixin to build URLs, but it's not that user-friendly because you can't use it in the templates, here's an example usage:

from emailtools import HTMLEmail
from emailtools.cbe.mixins import BuildAbsoluteURIMixin

class ThingCreatedAdminEmail(BuildAbsoluteURIMixin, HTMLEmail):
    template_name = 'things/mail/thing_created_admin.html'
    subject = "New Thing Created"

    def __init__(self, thing):
        self.thing = thing

    def get_to(self):
        return [user.email for user in User.objects.filter(is_superuser=True)]

    def get_context_data(self, **kwargs):
        kwargs = super(ThingCreatedAdminEmail, self).get_context_data(**kwargs)
        kwargs.update(
            thing=self.thing,
            detail_link=self.build_absolute_uri(self.thing.get_absolute_url()),
            admin_link=self.reverse_absolute_uri('admin:things_thing_change', args=(self.thing.pk,)),
        )
        return kwargs

send_thing_created_admin_email = ThingCreatedAdminEmail.as_callable()

The template could just output using {{ detail_link }} or {{ admin_link }}. This has the benefit of not needing the request. This is useful if you are sending emails when you don't have a request (like from a cron job), however, it does require you to set your django.contrib.sites up correctly.

If you wanted to send emails from a cron job, but still reverse the URLs in the template using something like absolute_uri, here's an implementation that uses the django.contrib.sites framework:

# myapp/templatetags/absolute_uri.py

from django import template
from django.core import urlresolvers

from django.contrib.sites.models import Site

register = template.Library()

def build_absolute_uri(path):
    site = Site.objects.get_current()
    return '{protocol}://{domain}{path}'.format(
        protocol='http',
        domain=site.domain,
        path=path
    )

@register.simple_tag
def absolute_uri(view_name, *args, **kwargs):
    """Reverse a URL and make it absolute."""
    path = urlresolvers.reverse(view_name, args=args, kwargs=kwargs)
    return build_absolute_uri(path)

@register.simple_tag
def absolutize(path):
    """Turn a relative URL into an absolute URL."""
    return build_absolute_uri(path)

(I modified this code before posting it, so I haven't tested it, but it's based on something that I've used before.)

I hope this answers your question. I am going to go ahead and close the issue. Please feel free to keep discussing this if you need some more clarification.

[jhagege]

Thank you so much for your thorough explanations, it proves very useful, and thanks again for this great package. It helps me understand better some OOP concepts in Python / Django.

Regards.

[rockymeza]

Thanks @cyberjoac, if you have any more questions, feel free to keep asking!

[pipermerriam]

And just a small follow-up @cyberjoac.

I would really recommend using a pattern that doesn't involve needing the request object to send your emails. By doing so, you've forced yourself into a corner where you always need a request object to trigger an email, meaning that you can't do things like sending them asynchronously with cron/celery, or even triggering them manually via the command line.

[rockymeza]

I wrapped that pattern I mentioned in the previous comment up in a django package, you can get it from PyPI:

https://pypi.python.org/pypi/django-absoluteuri/1.0.0

[pipermerriam]

LOVE IT!

[jhagege]

Thanks a lot!!!