Add function in utils to send multialternative emails using template renderer

coin/utils.py

@@ -3,6 +3,9 @@ import os
 import hashlib
 import binascii
 import base64
+import html2text
+from django.core.mail import EmailMultiAlternatives
+from django.template import TemplateDoesNotExist
 
 
 def str_or_none(obj):
@@ -22,3 +25,45 @@ def ldap_hash(password):
 
 if __name__ == '__main__':
     print(ldap_hash('coin'))
+
+
+def send_templated_email(subject, to, template_to_use, context, attachements, from_email=None):
+    """
+    Send a multialternative email based on html and optional txt template.
+    """
+    
+    # Get default sender if not specified
+    from_email = from_email if from_email else 'coin@illyse.org'
+    
+    # Ensure arrays when needed
+    if not isinstance(to, list):
+        to = [to] 
+    if not isinstance(attachements, list):
+        attachements = [attachements]
+
+    # If .html is specified in template name remove it
+    if template_to_use.endswith('.html'):
+        template_to_use = template_to_use[:-5]
+
+    # Get html template, fail if not exists
+    template_html = get_template('%s.html' % (template_to_use,))
+    html_content = template_html.render(Context(context))
+
+    # Try to get a txt version, convert from html to markdown style
+    # (using html2text) if fail
+    try:
+        template_txt = get_template('%s.txt' % (template_to_use,))
+        text_content = template_txt.render(Context(context))
+    except TemplateDoesNotExist:
+        text_content = html2text.html2text(html_content)
+    
+    # make multipart email default : text, alternative : html
+    msg = EmailMultiAlternatives(subject, text_content, from_email, to)
+    msg.attach_alternative(html_content, "text/html")
+    
+    # Set attachements
+    for attachement in attachements:
+        msg.attach_file(attachement)
+
+    #Send email
+    msg.send()

requirements.txt

@@ -8,5 +8,6 @@ python-dateutil==2.2
 django-autocomplete-light==2.0.0a8
 reportlab==2.5
 django-activelink==0.4
+html2text
 -e git+https://github.com/jmacul2/django-postgresql-netfields@2d6e597c3d65ba8b0e1f6e3183869216e990e915#egg=django-netfields
 -e git+https://github.com/chrisglass/xhtml2pdf@a5d37ffd0ccb0603bdf668198de0f21766816104#egg=xhtml2pdf-master