Problem with a request call Post in django

Question

I'm making a POST call for adding an event in the on_message() function at which step is a url to call the addEvent function (to add the event) and then a payload with values defined by me (inside the mqtt_iot file).

The compiler does not enter into the addEvent function, it locks but does not make any errors (I'm using the terminal). I enclose the code. How could I fix it?

In mqtt_Iot.py:

def on_message(client, userdata, msg):
    
    #convert byte json to json object and then to python dict to extract urls parameters
    byte_payload = msg.payload
    string_payload = byte_payload.decode('utf-8')
    data_dict = json.loads(string_payload)
    group_id = data_dict['group_id']
    calendar_id = data_dict['calendar_id']
    #in base al topic su cui ho ricevuto il messaggio faccio un azione o l'altra
    if ( msg.topic == "event/update"):
       #invio l'evento più prossimo alla board 
       client.publish(group_id,calendar_id)
    elif ( msg.topic == "event/new"):
       #il messaggio attiverà l'aggiunta di un evento facendo una post sul link adatto
       url = 'http://127.0.0.1:8000/homeProva1/%d/calendars/%d/events/new/' % (group_id,calendar_id)
       now= datet.datetime.now().time()
       end_time = datet.datetime.now() + datet.timedelta(hours=1)
       end_time = end_time.strftime("%H:%M:%S")
       now = now.strftime("%H:%M:%S")
       dt = datet.datetime.today()
       dt = dt.strftime("%Y-%m-%d")

       title = "Evento Node"
       description = "Evento prenotato in loco"
    
       payload = {"title": title, "day": dt, "start_time": now, "end_time": end_time, "notes":description}
       
       print("Payload")
       print(type(payload))
       print(payload)
       resp = requests.post(url,data=payload)
       content= response.content
       print (content)

In views.py:

def addEvent(request, pk=None ,pk1=None):
    print("sono dentro add event")
    instance = Event()
    instance = Event(calendar_id=pk1)
    
    form = EventForm(request.POST or None, instance=instance)
    if request.POST and form.is_valid():
        print(form)
        form.save()
        print("form valido")
        #controllo se evento appena aggiunto si svolgerà prima di un dato tempo ed in caso richiamo il publisher
        e = Event.objects.filter(calendar=pk1).latest('id')
        now= datetime.now().time()
        #trasformo orari in int per poter sottrarre
        now= int(now.strftime('%H%M%S'))
        temp= int(e.start_time.strftime('%H%M%S'))
        #se l'evento avviene fra meno di un ora chiamo la publish
        
        if((temp-now) < 6000):
           publish(pk,pk1)
        
        return HttpResponseRedirect(reverse('cal:home'))
    return render(request, 'cal/form.html', {'form': form})

In urls.py:

  path('homeProva1/<int:pk>/calendars/<int:pk1>/events/new/', views.addEvent, name='event_newprova1'),

In models.py:

class Event(models.Model):
    title = models.CharField(u'Title of the event', help_text=u'Title of the event', max_length=200, default='') 
    day = models.DateField(u'Day of the event', help_text=u'Day of the event')
    start_time = models.TimeField(u'Starting time', help_text=u'Starting time')
    end_time = models.TimeField(u'Final time', help_text=u'Final time')
    notes = models.TextField(u'Textual Notes', help_text=u'Textual Notes', blank=True, null=True)

    calendar = models.ForeignKey(Calendar, on_delete = models.CASCADE)

In forms.py:

class EventForm(ModelForm):
    class Meta:
        model = Event
        fields = ('title', 'day', 'start_time', 'end_time','notes',)

Answer 1

By combining the two request.POST and form.is_valid() you never render the validated form if it's invalid, so you never see the errors.

You need to simplify the logic in that view and ensure that the form when it contains errors gets returned to the page with the errors intact;

def addEvent(request, pk=None ,pk1=None):
    print("sono dentro add event")
    instance = Event()
    instance = Event(calendar_id=pk1)
    
    if request.method == "POST":
        form = EventForm(request.POST or None, instance=instance)
        if form.is_valid():
            form.save()
            print("form valido")
            #controllo se evento appena aggiunto si svolgerà prima di un dato tempo ed in caso richiamo il publisher
            e = Event.objects.filter(calendar=pk1).latest('id')
            now= datetime.now().time()
            #trasformo orari in int per poter sottrarre
            now= int(now.strftime('%H%M%S'))
            temp= int(e.start_time.strftime('%H%M%S'))
            #se l'evento avviene fra meno di un ora chiamo la publish
        
            if((temp-now) < 6000):
               publish(pk,pk1)
        
            return HttpResponseRedirect(reverse('cal:home'))
    else:
        # GET request
        form = EventForm(instance=instance)

    # An invalid POST request still hits here, where form contains errors
    return render(request, 'cal/form.html', {'form': form})

Then in your template make sure you display the non-field-errors as well as the field errors;

<form method="post" action=''>
    {% csrf_token %}

    {% if form.non_field_errors %}
        {{ form.non_field_errors }}
    {% endif %}

    {% for hidden in form.hidden_fields %}
        {{ hidden }}
    {% endfor %}

    {% for field in form.visible_fields %}
        <div class="fieldWrapper">
            {{ field.errors }}
            {{ field.label_tag }} {{ field }}
            {% if field.help_text %}
                <p class="help">{{ field.help_text|safe }}</p>
            {% endif %}
        </div>
    {% endfor %}

    <button type="button" value="submit">Submit</button>
    <button type="button" value="cancel">Cancel</button>
</form>