Embedding a Plotly chart in a Django template

Question

I am trying to embed a plotly pie chart in a Django html template. This works fine when the chart is produced in 'online mode' (i.e. the html snippet is stored on the plotly server) but not in 'offline mode' (i.e. when the html is stored locally). In the latter case, the chart does not appear. I want to be able to store the html on my local server and embed the plots from there.

Here is the bit that works:

import plotly.plotly as py
import plotly.graph_objs as go
labels = [1,2,3,4]
values = [10,20,30,40]
ndata = 100
fig = {
    'data': [{'labels': labels,
          'values': values,
          'type': 'pie',
          'textposition':"none",
          'textinfo':"percent",
          'textfont':{'size':'12'},
          'showlegend':'false'}],
    'layout': {'title': 'Total:'+str(ndata),
           'showlegend':'false',
           'height':'200',
           'width':'200',
           'autosize':'false',
           'margin':{'t':'50','l':'75','r':'0','b':'10'},
           'separators':'.,'}
}
plotly_url = py.plot(fig, filename='myfile', auto_open=False)
pie_url = '<iframe width="200" height="200" frameborder="0" seamless="seamless" scrolling="no" src='+plotly_url+'.embed?width=200&height=200&link=false&showlegend=false></iframe>'

Note that pie_url is passed as a string in the Http render request in Django. The template interprets the string as html using the | safe tag, i.e. {{ pie_url|safe }}.

Here is the bit that doesn't work:

from plotly.offline import download_plotlyjs, plot
import plotly.graph_objs as go
labels = [1,2,3,4]
values = [10,20,30,40]
ndata = 100
fig = {
    'data': [{'labels': labels,
          'values': values,
          'type': 'pie',
          'textposition':"none",
          'textinfo':"percent",
          'textfont':{'size':'12'},
          'showlegend':'false'}],
    'layout': {'title': 'Total:'+str(ndata),
           'showlegend':'false',
           'height':'200',
           'width':'200',
           'autosize':'false',
           'margin':{'t':'50','l':'75','r':'0','b':'10'},
           'separators':'.,'}
}
plotly_url = plot(fig, filename='file:///home/website/pie.html', auto_open=False)
pie_url = '''<iframe width="200" height="200" frameborder="0" seamless="seamless" scrolling="no" src=\"'''+plotly_url+'''.embed?width=200&height=200&link=false&showlegend=false\"></iframe>'''

Any advice would be appreciated.

Answer 1

Instead of writing the html to a file you can have plotly return the html part of the graph as a string. For example, using a class based TemplateView:

import plotly.offline as opy
import plotly.graph_objs as go

class Graph(TemplateView):
    template_name = 'graph.html'

    def get_context_data(self, **kwargs):
        context = super(Graph, self).get_context_data(**kwargs)

        x = [-2,0,4,6,7]
        y = [q**2-q+3 for q in x]
        trace1 = go.Scatter(x=x, y=y, marker={'color': 'red', 'symbol': 104, 'size': "10"},
                            mode="lines",  name='1st Trace')

        data=go.Data([trace1])
        layout=go.Layout(title="Meine Daten", xaxis={'title':'x1'}, yaxis={'title':'x2'})
        figure=go.Figure(data=data,layout=layout)
        div = opy.plot(figure, auto_open=False, output_type='div')

        context['graph'] = div

        return context

and the template:

{% if graph %}
<div style="width:600;height:500">
{{ graph|safe }}
</div>
{% endif %}