django: export current queryset to csv by button click in browser

Question

Hello experts! Could you please help. I have few views that return different querysets. my goal is to export current queryset to csv when user click button in browser.

Could you please recommend what is the best algorithm for doing this ? I already did all apart save query to csv only when button is clicked in browser.

Thank you in advance!

Answer 1

If you are using classed based views, its really easy (this is the sort of task where they shine). Subclass the main view, override the template and content type.

Here is an example from one of my projects

views.py

class SavedSamplesView(ListView):
    """
    This is the standard view returning HTML
    """
    template_name = "SavedSamples.html"
    model = Sample 
    context_object_name = "sample_list"

    def get_queryset(self) :
        slug =  self.kwargs['submission_slug']
        return Sample.objects.filter(submission__submission_slug=slug)

class SavedSamplesCsvView(SavedSamplesView):
    """
    Subclass of above view, to produce a csv file
    """
    template_name = 'SavedSamples.csv'
    content_type = 'text/csv'

The template SavedSamples.cvs looks like this (the formatting to get the newline is a little ugly, but it works). The first line is the headers, remove that if you don't need it:

sample.id , sample.name , ... , comments
{% for sample in sample_list %}{{ sample.id }},{{ sample.name }},....,{{sample.comments}}
{% endfor %}

urls.py

url(r'^savedsamplescsv/(?P<submission_slug>[ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz1234567890-_]+)/', views.SavedSamplesCsvView.as_view(),  name='saved_samples_csv'),

I would use a link instead of a button, and style it as button.