django - django：为模板提供动态（reportlab）png

Question

我在这个问题上花了一天的时间没有成功，所以我们将不胜感激。

我使用reportlab生成了一个图表，并使用本教程成功地将它呈现给浏览器：

        d = MyBarChartDrawing()

        #extract the request params of interest.
        #I suggest having a default for everything.
        if 'height' in request:
            d.height = int(request['height'])
        if 'width' in request:
            d.width = int(request['width'])

        if 'numbers' in request:
            strNumbers = request['numbers']
            numbers = map(int, strNumbers.split(','))    
            d.chart.data = [numbers]   #bar charts take a list-of-lists for data

        if 'title' in request:
            d.title.text = request['title']


        #get a GIF (or PNG, JPG, or whatever)
        binaryStuff = d.asString('png')

        return HttpResponse(binaryStuff, 'image/png')

不过我的问题是我想在模板中渲染这个 png，就像这样（不起作用）：

return render(request, "subscription/monitorSizes.html", {'form':form,'message':'','graph':binaryStuff})

多年来，我一直在研究这个问题。这无疑是一个新手问题！为了挽救我的理智，不胜感激这方面的建议。非常感谢 ：）

编辑：我在同一问题上发现了另一个stackoverflow Q，但并没有真正解决。

Answer 1

在views.py

def show_image(request):
    d = MyBarChartDrawing()
    #extract the request params of interest.
    #I suggest having a default for everything.
    if 'height' in request:
        d.height = int(request['height'])
    if 'width' in request:
        d.width = int(request['width'])

    if 'numbers' in request:
        strNumbers = request['numbers']
        numbers = map(int, strNumbers.split(','))    
        d.chart.data = [numbers]   #bar charts take a list-of-lists for data

    if 'title' in request:
        d.title.text = request['title']


    #get a GIF (or PNG, JPG, or whatever)
    binaryStuff = d.asString('png')

    return HttpResponse(binaryStuff, 'image/png')

def somepage(request):
     return render(request, "subscription/monitorSizes.html", {'form':form,'message':'','graph':reverse('show_image')})

在 urls.py

...
url(r'^show_image/$', 'your_view.show_image', name='show_image'),
url(r'^somepage/$', 'your_view.somepage', name='somepage'),
...

在订阅/monitorSizes.html

...
{% if graph != '' %} <img src="{{ graph }}" alt="some_text"> {% endif %}
...