为什么从其他 url 引导后文件上传在 Django 中不起作用？

Question

I want to do a simple web applications to let user to choose a task, where one of the tasks require file upload. In home , user is prompted to select task 1 or 2. After 2 is selected, it will enter another page to prompt user to upload file. I tried to follow a tutorial online for file upload but it does not work the way I wanted.

In views.py , I have the following functions:

def home(request):
 return render(request,'home.html')

def choice(request):
 name_1=request.GET['name_1']
 name_2=request.GET['name_2']
 if request.GET['choice']=='1':return render(request, "train.html",{"name_1":name_1, "name_2":name_2})
 elif request.GET['choice']=='2':return render(request, "train.html",{"name1":name_1, "name2":name_2})

 def predict(request):
  if request.method=="POST":
   document=request.FILES['document']
   print(document.name)
   print(document.size)
   return render(request,'predict.html')

For the urlpattern in urls.py ,

urlpatterns=[
    path('',views.home,name='home'),
    path('choice',views.choice, name='choice'),
    path('predict',views.predict,name='predict'),
    ]

The home.html is to prompt user to select task:

<h2>Select a Task:</h2>

<form action="choice">
    <select name="choice">
        <option value="1" selected >Train new model</option>
        <option value="2" >Prediction</option>
    </select>
    <br><br>
        System 1 is used to predict system 2 <br>
        Enter the name of system 1:<br>
        <input type="text" name="name_1"><br>
        Enter the name of system 2:<br>
        <input type="text" name="name_2"><br> 
        <input type="submit"></form><br><br>
</form>

The predict.html is the GUI to prompt user to upload file:

<br><h3>{{name_1}} is used to predict {{name_2}}</h3> 
Upload profiler logs:<br>
<form method="post" enctype="multipart/form-data">
    {% csrf_token %}
    <input type="file" name="document"><br><br>
    <button type="submit">Upload file</button>
</form>

So here is the question: When I directly access to http://127.0.0.1:8000/predict , after I have uploaded file, I can see document.name and document.size printed in the terminal as in predict function; but when I choose a task from home and being directed to predict , I cannot see document.name and document.size printed.

Why is it so?

Answer 1

in your views.py

change :

 name1=request.GET['name_1'] name2=request.GET['name_2']

to :

 name_1=request.GET['name1'] name_2=request.GET['name2']