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+==========================
+Outputting CSV with Django
+==========================
+
+This document explains how to output CSV (Comma Separated Values) dynamically
+using Django views. To do this, you can either use the `Python CSV library`_ or
+the Django template system.
+
+.. _Python CSV library: http://docs.python.org/library/csv.html
+
+Using the Python CSV library
+============================
+
+Python comes with a CSV library, ``csv``. The key to using it with Django is
+that the ``csv`` module's CSV-creation capability acts on file-like objects, and
+Django's :class:`~django.http.HttpResponse` objects are file-like objects.
+
+Here's an example::
+
+ import csv
+ from django.http import HttpResponse
+
+ def some_view(request):
+ # Create the HttpResponse object with the appropriate CSV header.
+ response = HttpResponse(mimetype='text/csv')
+ response['Content-Disposition'] = 'attachment; filename=somefilename.csv'
+
+ writer = csv.writer(response)
+ writer.writerow(['First row', 'Foo', 'Bar', 'Baz'])
+ writer.writerow(['Second row', 'A', 'B', 'C', '"Testing"', "Here's a quote"])
+
+ return response
+
+The code and comments should be self-explanatory, but a few things deserve a
+mention:
+
+ * The response gets a special MIME type, ``text/csv``. This tells
+ browsers that the document is a CSV file, rather than an HTML file. If
+ you leave this off, browsers will probably interpret the output as HTML,
+ which will result in ugly, scary gobbledygook in the browser window.
+
+ * The response gets an additional ``Content-Disposition`` header, which
+ contains the name of the CSV file. This filename is arbitrary; call it
+ whatever you want. It'll be used by browsers in the "Save as..."
+ dialogue, etc.
+
+ * Hooking into the CSV-generation API is easy: Just pass ``response`` as the
+ first argument to ``csv.writer``. The ``csv.writer`` function expects a
+ file-like object, and :class:`~django.http.HttpResponse` objects fit the
+ bill.
+
+ * For each row in your CSV file, call ``writer.writerow``, passing it an
+ iterable object such as a list or tuple.
+
+ * The CSV module takes care of quoting for you, so you don't have to worry
+ about escaping strings with quotes or commas in them. Just pass
+ ``writerow()`` your raw strings, and it'll do the right thing.
+
+Handling Unicode
+~~~~~~~~~~~~~~~~
+
+Python's ``csv`` module does not support Unicode input. Since Django uses
+Unicode internally this means strings read from sources such as
+:class:`~django.http.HttpRequest` are potentially problematic. There are a few
+options for handling this:
+
+ * Manually encode all Unicode objects to a compatible encoding.
+
+ * Use the ``UnicodeWriter`` class provided in the `csv module's examples
+ section`_.
+
+ * Use the `python-unicodecsv module`_, which aims to be a drop-in
+ replacement for ``csv`` that gracefully handles Unicode.
+
+For more information, see the Python `CSV File Reading and Writing`_
+documentation.
+
+.. _`csv module's examples section`: http://docs.python.org/library/csv.html#examples
+.. _`python-unicodecsv module`: https://github.com/jdunck/python-unicodecsv
+.. _`CSV File Reading and Writing`: http://docs.python.org/library/csv.html
+
+Using the template system
+=========================
+
+Alternatively, you can use the :doc:`Django template system </topics/templates>`
+to generate CSV. This is lower-level than using the convenient Python ``csv``
+module, but the solution is presented here for completeness.
+
+The idea here is to pass a list of items to your template, and have the
+template output the commas in a :ttag:`for` loop.
+
+Here's an example, which generates the same CSV file as above::
+
+ from django.http import HttpResponse
+ from django.template import loader, Context
+
+ def some_view(request):
+ # Create the HttpResponse object with the appropriate CSV header.
+ response = HttpResponse(mimetype='text/csv')
+ response['Content-Disposition'] = 'attachment; filename=somefilename.csv'
+
+ # The data is hard-coded here, but you could load it from a database or
+ # some other source.
+ csv_data = (
+ ('First row', 'Foo', 'Bar', 'Baz'),
+ ('Second row', 'A', 'B', 'C', '"Testing"', "Here's a quote"),
+ )
+
+ t = loader.get_template('my_template_name.txt')
+ c = Context({
+ 'data': csv_data,
+ })
+ response.write(t.render(c))
+ return response
+
+The only difference between this example and the previous example is that this
+one uses template loading instead of the CSV module. The rest of the code --
+such as the ``mimetype='text/csv'`` -- is the same.
+
+Then, create the template ``my_template_name.txt``, with this template code:
+
+.. code-block:: html+django
+
+ {% for row in data %}"{{ row.0|addslashes }}", "{{ row.1|addslashes }}", "{{ row.2|addslashes }}", "{{ row.3|addslashes }}", "{{ row.4|addslashes }}"
+ {% endfor %}
+
+This template is quite basic. It just iterates over the given data and displays
+a line of CSV for each row. It uses the :tfilter:`addslashes` template filter to
+ensure there aren't any problems with quotes.
+
+Other text-based formats
+========================
+
+Notice that there isn't very much specific to CSV here -- just the specific
+output format. You can use either of these techniques to output any text-based
+format you can dream of. You can also use a similar technique to generate
+arbitrary binary data; see :doc:`/howto/outputting-pdf` for an example.