python - 如何用amcharts和django实时显示数据？

Question

我希望图表自己刷新(而不是刷新整个网页)，就像心脏监视器一样，每次将新数据添加到数据库中时，这可能吗？

使用下面的代码，我必须刷新网页并查看是否有任何新数据。

views.py:

from tempsensors.models import temp

def temp_page(request):
#this view is to store the temperature value into my database
#data is send by my board with a temperature sensor
if request.method == 'POST' and 'tem' in request.POST and request.POST['tem']:
    temp_value = float(request.POST['tem']) 
    temp_add = temp(temp=temp_value)
    temp_add.save()
else:
#only for post data
    raise Http404
return render_to_response("temp.html",locals(),context_instance=RequestContext(request))

def chart_page(request):
    #this view will display a chart
    temps = temp.objects.all()
    # formatting JSON file
    prefix = ''
    chartData = "[" 
    for t in temps:
        chartData += prefix
        chartData += "{\n" 
        chartData += "                      date: "
        chartData += "new Date(" + str(t.temp_date.year) + "," 
        chartData += str(t.temp_date.month-1) + "," 
        chartData += str(t.temp_date.day) + "," 
        chartData += str(t.temp_date.hour) + "," 
        chartData += str(t.temp_date.minute) + "),\n"
        chartData += "                      value: "
        chartData += str(t.temp) + "\n                      }"
        prefix = ", "
    chartData += "]" 
    temp_now = temp.objects.order_by("-id")[0].temp
    return render_to_response('chart.html', locals())

图表.html

var chartData = {{chartData}}
chart.dataProvider = chartData;

Answer 1

如果您希望数据“实时”流式传输到页面，您将必须有一些框架来做到这一点。 Django 的作用就是生成 html，并在页面请求时返回所需的数据，但您想要的是 POST 之后的数据传输。为此，我建议查看 socket.io 。可以找到一个很好的示例项目，帮助我了解它如何与 django 集成 here on github .

希望这可以帮助您入门。