def get_download_module(module_name):
import re
if not re.search('^[a-zA-Z0-9\_\.]+$', module_name): # pragma: no cover
# bad module_name
raise registry_exceptions.BadDownloadModuleName("Download name isn't a valid Python module name.")
try:
return import_module("%s.downloader" % module_name)
except:
debug = getattr(settings, 'DEBUG')
if debug:
raise
return None
def get_download_module(module_name):
import re
if not re.search('^[a-zA-Z0-9\_\.]+$', module_name): # pragma: no cover
# bad module_name
raise registry_exceptions.BadDownloadModuleName(
"Download name isn't a valid Python module name.")
try:
downloader = None
# dangerous - we are really trusting the settings creators here.
exec("import %s.downloader as downloader" % module_name)
return downloader
except:
debug = getattr(settings, 'DEBUG')
if debug:
raise
return None
def download(request, downloadType, iid=None):
"""
By default, ``aristotle_mdr.views.download`` is called whenever a URL matches
the pattern defined in ``aristotle_mdr.urls_aristotle``::
download/(?P<downloadType>[a-zA-Z0-9\-\.]+)/(?P<iid>\d+)/?
This is passed into ``download`` which resolves the item id (``iid``), and
determins if a user has permission to view the request item with that id. If
a user is allowed to download this file, ``download`` iterates through each
download type defined in ``ARISTOTLE_DOWNLOADS``.
A download option tuple takes the following form form::
('file_type','display_name','font_awesome_icon_name','module_name'),
With ``file_type`` allowing only ASCII alphanumeric and underscores,
``display_name`` can be any valid python string,
``font_awesome_icon_name`` can be any Font Awesome icon and
``module_name`` is the name of the python module that provides a downloader
for this file type.
For example, included with Aristotle-MDR is a PDF downloader which has the
download definition tuple::
('pdf','PDF','fa-file-pdf-o','aristotle_mdr'),
Where a ``file_type`` multiple is defined multiple times, **the last matching
instance in the tuple is used**.
Next, the module that is defined for a ``file_type`` is dynamically imported using
``exec``, and is wrapped in a ``try: except`` block to catch any exceptions. If
the ``module_name`` does not match the regex ``^[a-zA-Z0-9\_]+$`` ``download``
raises an exception.
If the module is able to be imported, ``downloader.py`` from the given module
is imported, this file **MUST** have a ``download`` function defined which returns
a Django ``HttpResponse`` object of some form.
"""
item = MDR._concept.objects.get_subclass(pk=iid)
item = get_if_user_can_view(item.__class__, request.user, iid)
if not item:
if request.user.is_anonymous():
return redirect(reverse('friendly_login') + '?next=%s' % request.path)
else:
raise PermissionDenied
downloadOpts = getattr(settings, 'ARISTOTLE_DOWNLOADS', "")
module_name = ""
for d in downloadOpts:
dt = d[0]
if dt == downloadType:
module_name = d[3]
if module_name:
import re
if not re.search('^[a-zA-Z0-9\-\.]+$', downloadType): # pragma: no cover
# Invalid downloadType
raise registry_exceptions.BadDownloadTypeAbbreviation("Download type can only be composed of letters, numbers, hyphens or periods.")
elif not re.search('^[a-zA-Z0-9\_]+$', module_name): # pragma: no cover
# bad module_name
raise registry_exceptions.BadDownloadModuleName("Download name isn't a valid Python module name.")
try:
downloader = None
# dangerous - we are really trusting the settings creators here.
exec("import %s.downloader as downloader" % module_name)
return downloader.download(request, downloadType, item)
except TemplateDoesNotExist:
raise Http404
raise Http404