Django Function

Using Django Getting Started
1

I am using django. I have added the below function into my views.py file. When I first start vs code the holehe GUI executes and the window pops up for me to enter text, I know it works. However when I start the server and click the button on the holehe HTML page I receive the error “The view website.views.buttonclick2 didn’t return an HttpResponse object. It returned None instead.”

I have tried adding at the bottom return render(request, ‘holehe.html’) however this doesn’t work.

Basically when I click the button on the holehe page the terminal window should open.

Please can someone advise where I am going wrong ?

my view looks like this:

def buttonclick2(request):
    if request.method == "POST":
        return 
                
def compile_terminal_command(terminal_command, last_line_index) :
                

    # The last line index stores the line where the command thread has to output in the 
     listbox
    # since the listbox may have also received more commands in that span and the thread may 
    take
    # some time to give output
    
    command_summary = terminal_command.split(' ') # Split the command and args.
    os.environ["PYTHONUNBUFFERED"] = "1" # MAKE SURE THE PREVIOUS OUTPUT IS NOT RECIEVED
    
    # > We use the subprocess module's run method to run the command and redirect output and 
     errors
    # to the pipe from where we can extract it later.
    # > I will suggest running this with shell = True since that was the way it was working 
    for me and was
    # not working with shell = False for some reason.
    # > Also the current working directory argument can be passed but did not work in my case 
    where i set
    # the current working directory to the system drive C: in my case and put a python file 
     there
    # when I ran the file it did not run and picked up my local directory and not the C:
    result = subprocess.run(command_summary, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, `shell = True, env = os.environ)`
    
    output = result.stdout
    # To make sure we print output line by line and not in one single line we use splitlines.
    output_lines = output.splitlines()
    for k in output_lines :
        terminal_listbox.insert(last_line_index, k)
        last_line_index += 21 # Increases line index to make sure output is printed line by line.
    
    return
 
def refresh_terminal(backspace = False) :
    # refreshes the terminal when a change is done to terminal by the user.
    global terminal_text
    
    if terminal_text != '>>holehe ' or backspace :
        terminal_listbox.delete(tk.END)
    terminal_listbox.insert(tk.END, terminal_text)
    return
 
def append_to_terminal_text(text) :
    # can append a single character or more to the terminal
    global terminal_text
    
    terminal_listbox.delete(tk.END)
    terminal_text = terminal_text + text
    terminal_listbox.insert(tk.END, terminal_text)
    terminal_listbox.yview_moveto(1)
    return
 
def terminal_enter_key_callback() :
    global terminal_text
    
    # The thread that compiles the output is run in background to make sure it does not hang the
    # program or does not stop the terminal incase the output is taking time to be generated.
    compiler_thread = threading.Thread(target = compile_terminal_command, args = (terminal_text[3 : ], terminal_listbox.size()))
    compiler_thread.daemon = True
    compiler_thread.start()
    
    terminal_text = '>> ' # Resetting the terminal_text variable that stores the text of the current line of the terminal.
    
    terminal_listbox.insert(tk.END, terminal_text) # Insert the terminal text(basically a new line in this case) to the terminal listbox.
    terminal_listbox.yview_moveto(1) # scrolls down the listbox down to the very last.
    return
 
def type_to_terminal(string) :
    # types a given string automatically to the terminal.
    for k in string :
        append_to_terminal_text(k)
    
    terminal_listbox.yview_moveto(1)
    return
 
def terminal_backspace_callback() :
    # callback for backspace key erases the last character.
    global terminal_text
    
    if len(terminal_text) > 3 :
        terminal_text = terminal_text[ : -1]

    refresh_terminal(backspace = True)
    return
 
root = tk.Tk()
root.title('GAEN - holehe command line GUI')
root.geometry('800x800')
 
# Making a frame, this terminal frame can be packed or used as a toplevel window instead.
terminal = tk.Frame(root, bg = 'black')


 
# Initializing a listbox to act as terminal with bg and fg of your own choice.
# NOTE:  in the listbox to make it so the selection of listbox items is not visible
# I have changed the highlight color and select color to background color and also have set
# the active style i.e. the style used to display a selection to tk.NONE, and have also set
# the highlight thickness to 0.
terminal_listbox = tk.Listbox(terminal, bg = 'black', fg = 'white', highlightcolor = 'black', highlightthickness = 0, selectbackground = 'black', activestyle = tk.NONE)
terminal_scrollbar = tk.Scrollbar(terminal)
terminal_scrollbar.pack(side = tk.RIGHT, fill = tk.Y)
 
# packing and stuff.
terminal_listbox.pack(expand = True, fill = tk.BOTH)
terminal.pack(expand = True, fill = tk.BOTH)
 
# Inserting the copyright thingy.
terminal_listbox.insert(tk.END, 'Terminal for holehe')
terminal_listbox.insert(tk.END, 'By GAEN')
terminal_listbox.insert(tk.END, '')
terminal_listbox.insert(tk.END, '')
terminal_listbox.insert(tk.END, 'To use type: holehe email@address')
terminal_listbox.insert(tk.END, 'Press enter')
terminal_listbox.insert(tk.END, 'wait a moment......')
terminal_listbox.insert(tk.END, '')
terminal_listbox.insert(tk.END, '')
terminal_listbox.insert(tk.END, '+ sign means email address on that site')


# Intializes the terminal text for the first line.
terminal_text = '>>holehe_ '
 
# Assigns a scrollbar to the terminal.
terminal_listbox.config(yscrollcommand = terminal_scrollbar.set)
terminal_scrollbar.config(command = terminal_listbox.yview)
 
# THE FIRST EVER INSERTED ITEM DOES NOT APPEAR SO THIS IS A BUFFER ITEM TO FILL THAT SPOT

terminal_listbox.insert(tk.END, '')
terminal_listbox.insert(tk.END, '')
 
append_to_terminal_text('') # Buffer.

 
# SETTING UP BINDINGS FOR ENTER AND BACKSPACE CALLBACKS WITH THEIR RESPECTIVE KEYS
terminal_listbox.bind('<Return>', lambda x : terminal_enter_key_callback())
terminal_listbox.bind('<BackSpace>', lambda x : terminal_backspace_callback())
 
# SETTING UP KEYBOARD INPUT FOR A LISTBOX HARDCODINGLY.
terminal_listbox.bind('a', lambda x : append_to_terminal_text('a'))
terminal_listbox.bind('b', lambda x : append_to_terminal_text('b'))
terminal_listbox.bind('c', lambda x : append_to_terminal_text('c'))
terminal_listbox.bind('d', lambda x : append_to_terminal_text('d'))
terminal_listbox.bind('e', lambda x : append_to_terminal_text('e'))
terminal_listbox.bind('f', lambda x : append_to_terminal_text('f'))
terminal_listbox.bind('g', lambda x : append_to_terminal_text('g'))
terminal_listbox.bind('h', lambda x : append_to_terminal_text('h'))
terminal_listbox.bind('i', lambda x : append_to_terminal_text('i'))
terminal_listbox.bind('j', lambda x : append_to_terminal_text('j'))
terminal_listbox.bind('k', lambda x : append_to_terminal_text('k'))
terminal_listbox.bind('l', lambda x : append_to_terminal_text('l'))
terminal_listbox.bind('m', lambda x : append_to_terminal_text('m'))
terminal_listbox.bind('n', lambda x : append_to_terminal_text('n'))
terminal_listbox.bind('o', lambda x : append_to_terminal_text('o'))
terminal_listbox.bind('p', lambda x : append_to_terminal_text('p'))
terminal_listbox.bind('q', lambda x : append_to_terminal_text('q'))
terminal_listbox.bind('r', lambda x : append_to_terminal_text('r'))
terminal_listbox.bind('s', lambda x : append_to_terminal_text('s'))
terminal_listbox.bind('t', lambda x : append_to_terminal_text('t'))
terminal_listbox.bind('u', lambda x : append_to_terminal_text('u'))
terminal_listbox.bind('v', lambda x : append_to_terminal_text('v'))
terminal_listbox.bind('w', lambda x : append_to_terminal_text('w'))
terminal_listbox.bind('x', lambda x : append_to_terminal_text('x'))
terminal_listbox.bind('y', lambda x : append_to_terminal_text('y'))
terminal_listbox.bind('z', lambda x : append_to_terminal_text('z'))

terminal_listbox.bind('A', lambda x : append_to_terminal_text('A'))
terminal_listbox.bind('B', lambda x : append_to_terminal_text('B'))
terminal_listbox.bind('C', lambda x : append_to_terminal_text('C'))
terminal_listbox.bind('D', lambda x : append_to_terminal_text('D'))
terminal_listbox.bind('E', lambda x : append_to_terminal_text('E'))
terminal_listbox.bind('F', lambda x : append_to_terminal_text('F'))
terminal_listbox.bind('G', lambda x : append_to_terminal_text('G'))
terminal_listbox.bind('H', lambda x : append_to_terminal_text('H'))
terminal_listbox.bind('I', lambda x : append_to_terminal_text('I'))
terminal_listbox.bind('J', lambda x : append_to_terminal_text('J'))
terminal_listbox.bind('K', lambda x : append_to_terminal_text('K'))
terminal_listbox.bind('L', lambda x : append_to_terminal_text('L'))
terminal_listbox.bind('M', lambda x : append_to_terminal_text('M'))
terminal_listbox.bind('N', lambda x : append_to_terminal_text('N'))
terminal_listbox.bind('O', lambda x : append_to_terminal_text('O'))
terminal_listbox.bind('P', lambda x : append_to_terminal_text('P'))
terminal_listbox.bind('Q', lambda x : append_to_terminal_text('Q'))
terminal_listbox.bind('R', lambda x : append_to_terminal_text('R'))
terminal_listbox.bind('S', lambda x : append_to_terminal_text('S'))
terminal_listbox.bind('T', lambda x : append_to_terminal_text('T'))
terminal_listbox.bind('U', lambda x : append_to_terminal_text('U'))
terminal_listbox.bind('V', lambda x : append_to_terminal_text('V'))
terminal_listbox.bind('W', lambda x : append_to_terminal_text('W'))
terminal_listbox.bind('X', lambda x : append_to_terminal_text('X'))
terminal_listbox.bind('Y', lambda x : append_to_terminal_text('Y'))
terminal_listbox.bind('Z', lambda x : append_to_terminal_text('Z'))
terminal_listbox.bind('1', lambda x : append_to_terminal_text('1'))
terminal_listbox.bind('2', lambda x : append_to_terminal_text('2'))
terminal_listbox.bind('3', lambda x : append_to_terminal_text('3'))
terminal_listbox.bind('4', lambda x : append_to_terminal_text('4'))
terminal_listbox.bind('5', lambda x : append_to_terminal_text('5'))
terminal_listbox.bind('6', lambda x : append_to_terminal_text('6'))
terminal_listbox.bind('7', lambda x : append_to_terminal_text('7'))
terminal_listbox.bind('8', lambda x : append_to_terminal_text('8'))
terminal_listbox.bind('9', lambda x : append_to_terminal_text('9'))
terminal_listbox.bind('0', lambda x : append_to_terminal_text('0'))
terminal_listbox.bind('.', lambda x : append_to_terminal_text('.'))
terminal_listbox.bind(':', lambda x : append_to_terminal_text(':'))
terminal_listbox.bind('@', lambda x : append_to_terminal_text('@'))
terminal_listbox.bind('-', lambda x : append_to_terminal_text('-'))
terminal_listbox.bind('_', lambda x : append_to_terminal_text('_'))
terminal_listbox.bind('?', lambda x : append_to_terminal_text('?'))
terminal_listbox.bind('=', lambda x : append_to_terminal_text('='))
terminal_listbox.bind('<slash>', lambda x : append_to_terminal_text('/'))
terminal_listbox.bind('<backslash>', lambda x : append_to_terminal_text('\\'))
terminal_listbox.bind('<space>', lambda x : append_to_terminal_text(' '))
# Not all keys have been binded here as its a demonstration but as per need all can be binded.          
                            

root.mainloop()
2

Have you worked your way through either the Official Django Tutorial or the Django Girls Tutorial to understand what views are and how they work?

If you haven’t, that’s the first step.

If you have, then you may want to review the docs at Writing views | Django documentation | Django

3

I have used the tutorials thank you.

However I’m faced with the same problem hence why I posted here. But if you can point me in the right direction of something I would be thankful.

4

So what exactly is the error message telling you?

What do you think you need to do to resolve it?

5

I get the error The view website.views.buttonclick2 didn’t return an HttpResponse object. It returned None instead.

But if I return a html then my script wont run and only the page appears. I want the script to run.

6

That’s a different issue.

From what you’ve posted, your “script” is defined as a function.

Your view is also a function.

How do you use a function from a different function?

7

I apologise for using the wrong words. Im new to python. You can see from my initial message what the spirit of my question is.

But ok I will retype. My function in the views.py file. The one I have copied and pasted above. I feel the need to point this out so there is no further confusion.

The page loads fine. The button is present on the page when it loads. When I click the button to run the script I get the before mentioned error.

So I need the function def compile_terminal_command and all the functions below it to run when the button is clicked.

I am having problems doing this but I dont understand why.

8

So, you’ve identified the error.

Your view function is not allowed to return None - it must return an HttpResponse object.

That your script doesn’t run when you do that is a different problem.

Fix the view first, then we’ll move on to the rest.

9

Im sorry i dont understand.

My first view works as the page is displayed.

The view for my function doesnt work and its that what I am struggling with. If i return render(request) then the rest of the function doesnt run.

?

10

I looked ahead at the rest of your script - you’ve got one fundamental issue that is going to be really difficult to resolve.

Your script, as written, isn’t going to work the way you want to use it.

The bulk of your script performs console-style interaction. This doesn’t work in a web environment. You do not have access to a console through a web page.

You will need to re-engineer your script to accept input through web forms and generate output as html.

11

What are you calling your “view” in this specific case? I thought you have been talking about buttonclick2.

12

Buttonclick2 is a function sat in the views.py

When i click the button i receive the before mentioned error. However thank you for looking through the code. Im guessing no matter whst it will never run.

Can you point me in the right direction of what i should be reading etc to re-engineer it to work this way ?

13

You will need to understand how the original code works - what the inputs and outputs are and how the code functions to produce that output. (You’re only going to get that information from the code itself.)

Then you need to understand how web applications work. You need to work your way through tutorials or other materials to the point where you understand why you’re doing what you’re doing. Just typing in code isn’t going to help if you’re not learning what each of those lines do.