def get(self, request, chart_type, id=None):
"""generate info into a response"""
# TODO, sanitize the GET.... (pass format=png/pdf, size etc?)
try:
if chart_type in ['eeg', 'jarkustimeseries']:
id = int(id)
transect = makejarkustransect(id)
if chart_type == 'eeg':
fd = eeg(transect, {'format':'png'})
elif chart_type == 'jarkustimeseries':
fd = jarkustimeseries(transect, {'format':'png'})
elif chart_type == 'jarkusmean':
id_min = int(request.GET['id_min']) # e.g. 7003001
id_max = int(request.GET['id_max']) # e.g. 7003150
fd = jarkusmean(id_min, id_max, settings.NC_RESOURCE, {'format':'png'})
# wrap the file descriptor as a generator (8 KB reads)
wrapper = FileWrapper(fd)
response = HttpResponse(wrapper, content_type="image/png")
# TODO for pdf:
# response['Content-Disposition'] = 'attachment; filename=transect{}.{}'.format(self.id, format=format)
except WouldTakeTooLong:
response = HttpResponseRedirect(settings.STATIC_URL + 'lizard_kml/graph_not_loaded_error.png')
return response
def get(self, request, chart_type, id=None, format='png'):
year_from = request.GET.get('year_from')
year_to = request.GET.get('year_to')
width = request.GET.get('width')
height = request.GET.get('height')
dt_from = datetime.datetime(int(year_from), 1, 1) if year_from else None
dt_to = datetime.datetime(int(year_to), 12, 31, 23, 59, 59) if year_to else None
# When set, override the format with the passed GET parameter 'format'.
format = request.GET.get('format', format)
if format not in ['svg', 'png', 'pdf']:
raise Http404
# Sanitize transect IDs by converting them to ints.
if id:
id = int(id)
id_min = request.GET.get('id_min') # e.g. 7003001
id_max = request.GET.get('id_max') # e.g. 7003150
if id_min and id_max:
id_min = int(id_min)
id_max = int(id_max)
try:
dpi = 100 # matplotlib default DPI
plotproperties = {
'format': format,
'dpi': dpi
}
if width and height:
figsize = (float(width) / dpi, float(height) / dpi)
else:
figsize = None
# Determine what function to use to render the chart.
if chart_type == 'eeg':
transect = makejarkustransect(id, dt_from, dt_to)
fd = eeg(transect, plotproperties, figsize)
elif chart_type == 'jarkustimeseries':
transect = makejarkustransect(id, dt_from, dt_to)
fd = jarkustimeseries(transect, plotproperties, figsize)
elif chart_type == 'nourishment':
fd = nourishment(id, dt_from, dt_to, plotproperties, figsize)
elif chart_type == 'jarkusmean':
fd = jarkusmean(id_min, id_max, plotproperties, figsize)
else:
raise Exception('Unknown chart type')
except Exception as ex:
logger.exception('exception while rendering chart')
fd = message_in_png(traceback.format_exc(), width, height)
format = 'png'
# Wrap the file descriptor as a generator (8 KB reads).
wrapper = FileWrapper(fd)
# Determine correct mimetype.
if format == 'svg':
mimetype = 'image/svg+xml'
else:
mimetype = mimetypes.types_map['.%s' % format]
# Build a response which streams the wrapped buffer.
response = HttpResponse(wrapper, content_type=mimetype)
# Add a header containing the filename, so the browser knows how to call the saved file.
if self.download:
if id_min and id_max:
id_str = '{0}-{1}'.format(id_min, id_max)
elif id:
id_str = str(id)
else:
id_str = ''
response['Content-Disposition'] = 'attachment; filename=transect-{0}-{1}.{2}'.format(id_str, chart_type, format)
return response
