如何在Django 2中将变量从html注入到views.py？

Question

I tried some ways but none worked. The button should scrape weather from city typed in the text box. All scraping works when I hardcode city name but I don't know how to get that city name from HTML form to views.py .

html :

<form method="POST "action="{% url 'weather' %}">
{% csrf_token %}
    <input  type="text" value="{{ city }}">
    <button type="submit" class="btn btn-info">Get my weather</button>
</form>

views.py

def scrape_weather(request):
    old_weather = Weather.objects.all()
    old_weather.delete()
    api_adress = "http://api.openweathermap.org/data/2.5/weather?q="
    api_key = "&appid=3a99cf24b53d85f4afad6cafe99d3a34"
    city = input()
    #city = "warsaw"
    url = api_adress + city + api_key

    json_data = requests.get(url).json()
    new_weather = json_data['weather'][0]['main']
    degree_kelvin = int(json_data['main']['temp'])
    degree = degree_kelvin-273
    pressure = json_data['main']['pressure']

    new_weather = Weather()
    new_weather.degree = degree
    new_weather.pressure = pressure

    new_weather.weather = new_weather
    new_weather.save()
    if request.method == 'POST':
        form = CityForm(request.POST)
        if form.is_valid():
            pass
    else:
        form = CityForm() 
    return render(request, "news/home.html", {'form': form})

forms.py :

from django import forms

class CityForm(forms.Form):
    city = forms.CharField(max_length=30)

    if not city:
        raise forms.ValidationError('You have to write something!')

Answer 1

This has nothing to do with scraping or injecting. For a browser to send a value from an input field, the field element needs to have a name attribute.

<input  type="text" name="city">

and then get it in the view:

city = request.POST.get("city")

Note, I'm not at all sure why you have the CityForm, you aren't using it.

Answer 2

In your template you can:

<form method="POST "action="{% url 'weather' %}">
{% csrf_token %}
    {{ form }}
    <button type="submit" class="btn btn-info">Get my weather</button>
</form>

That will manage all the business of widget( text input in this case) attributes such as name for you.

Read this for more detail.