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Django-filter pagination only the first search filed failed

I'm using django-filter with pagination, as long as the search filed is in the first place in filter.py -> fields = ['name_procss','typeLevel'] list, the pagination for filter of that filed will not work.
fitler.py:
import django_filters
from MyCore.models import MyRunStats
class MyRunStatsFilter(django_filters.FilterSet):
def gen_choice(self,filed):
return tuple((l, l) for l in list(MyRunStats.objects.exclude(**{filed: None}).values_list(filed, flat=True).distinct()))
name_procss = django_filters.ChoiceFilter(label='Process',choices=tuple,null_label='None',null_value='null')
typeLevel = django_filters.ChoiceFilter(label='Message Type',choices=tuple,null_label='None',null_value='null')
class Meta:
model = MyRunStats
fields = ['name_procss','typeLevel']
def __init__(self, *args, **kwargs):
super(MyRunStatsFilter, self).__init__(*args, **kwargs)
self.filters['name_procss'].extra['choices'] = self.gen_choice('name_procss')
self.filters['typeLevel'].extra['choices'] = self.gen_choice('typeLevel')
Views.py
def runstat_hist_view_render(request):
all_obj = MyRunStats.objects.all().order_by('-create_dttm')
hist_filter = MyRunStatsFilter(request.GET, queryset=all_obj)
paginator= Paginator(hist_filter.qs[:57], 20)
page = request.GET.get('page')
try:
response = paginator.page(page)
except PageNotAnInteger:
response = paginator.page(1)
except EmptyPage:
response = paginator.page(paginator.num_pages)
context = {'response': response,'filter': hist_filter}
return render(request, 'My/My_runstat_hist.html',context)
html:
<form method="get" >
{{ filter.form}}
<button type="button" onclick="submitFilter()" id="hist-search-button" >Search Message</button>
</form>
{% for item in response %}
<nav>
<ul class="pagination">
{% if response.has_previous %}
<li>« First</li>
<li >Previous</li>
{% else %}
<li>Previous</li>
{% endif %}
{% for num in response.paginator.page_range %}
{% if response.number == num %}
<li>{{num}}</li>
{% elif num > response.number|add:'-3' and num < response.number|add:'3' %}
<li>{{num}}</li>
{% endif %}
{% endfor %}
{% if response.has_next %}
<li>Next</li>
<li>Last »</li>
{% else %}
<li>Next</li>
{% endif %}
</ul>
</nav>
The issue is ,no matter which item is in the first place in filter.py->fields = ['name_procss','typeLevel'],for example now the 'name_procss' is in the first place ,then the pagination for 'name_procss' not work,if I put 'typeLevel' in the first place ,then pagination for 'typeLevel' will not work but for 'name_procss' will work.

Adding a maximum limit to the number of post using python

I need to limit the number of posts in Django queries. I have tried to add a min and max but nothing seemed to have worked. I have added home.html into the code.
Example: I should only have the 15 most recent posts in my blog. The rest can be seen by clicking on the category button.
Home.html:
{% extends 'base.html' %}
{% block content %}
<h1>Posts</h1>
<ul>
{% for post in object_list %}
<li>{{post.title}}
<style>
a {
text-transform: capitalize;
}
</style>
- {{ post.category }} - <a href="{% url 'show_profile_page' post.author.profile.id %}">{{ post.author.first_name }}
{{ post.author.last_name }}</a> - {{ post.post_date }} <small>
{% if user.is_authenticated %}
{% if user.id == post.author.id %}
- (Edit)
(Delete)
{% elif user.id == 1 %}
- (Edit)
(Delete)
{% endif %}
{% endif %}
</small><br/>
{{ post.snippet }}</li>
{% endfor %}
</ul>
{% endblock %}
view.py:
class HomeView(ListView):
model = Post
template_name = 'home.html'
ordering = ['-id']
def get_context_data(self, *args, **kwargs):
cat_menu = Category.objects.all()
context = super(HomeView, self).get_context_data(*args,**kwargs)
context["cat_menu"] = cat_menu
return context
models.py:
class Post(models.Model):
title = models.CharField(max_length=255)
header_image = models.ImageField(null=True, blank=True, upload_to='images/')
title_tag = models.CharField(max_length=255)
author = models.ForeignKey(User, on_delete=models.CASCADE)
body = RichTextField(blank=True, null=True)
post_date = models.DateField(auto_now_add=True)
category = models.CharField(max_length=255, default='intro')
snippet = models.CharField(max_length=255)
likes = models.ManyToManyField(User, related_name='post_likes')
dislikes = models.ManyToManyField(User, related_name='post_dislikes')

I think you have another template for displaying categorised objects when you click category button. As you said
"I should only have the 15 most recent posts in my blog. The rest can
be seen by clicking on the category button."
In this case you can use a simple hack to display most recent posts from your table.
query all objects in descending order in views
all_objs = Post.objects.all().order_by('-id')
Then use {% if forloop.counter <= 15 %} to display last 15 items only. as follow.
templates
{% for post in object_list %}
{% if forloop.counter <= 15 %}
<h4>{{obj}} #or anything really that is meant to be shown on the home page.</h4>
{% endif %}
{% endfor %}

You can do something like this:
def get_context_data(self, *args, **kwargs):
context = super(HomeView, self).get_context_data(*args,**kwargs)
context["cat_menu"] = Category.objects.all()
context["most_recent_posts"] = Post.objects.filter(author=self.request.user).order_by('-post_date')[:15]
return context
This will get the 15 most recent posts authored by the current user, ordered by the date it was posted.
Then just handle displaying this in home.html for example:
<ul>
{% for p in most_recent_posts %}
<li>{{ p.title }}</li>
{% endfor %}
</ul>

Just limit your query to the latest 15 entries sorted by post_date:
cat_menu = Category.objects.latest("post_date")[:15]

https://docs.djangoproject.com/en/3.2/topics/pagination/
The best way is Django Pagintion.
{% for contact in page_obj %}
{# Each "contact" is a Contact model object. #}
{{ contact.full_name|upper }}<br>
...
{% endfor %}
<div class="pagination">
<span class="step-links">
{% if page_obj.has_previous %}
« first
previous
{% endif %}
<span class="current">
Page {{ page_obj.number }} of {{ page_obj.paginator.num_pages }}.
</span>
{% if page_obj.has_next %}
next
last »
{% endif %}
</span>
</div>
from django.core.paginator import Paginator
from django.shortcuts import render
from myapp.models import Contact
def listing(request):
contact_list = Contact.objects.all()
paginator = Paginator(contact_list, 25) # Show 25 contacts per page.
page_number = request.GET.get('page')
page_obj = paginator.get_page(page_number)
return render(request, 'list.html', {'page_obj': page_obj})

you can use Django pagination api . Manage your data through page number. Initially pass 1 and after that page number given by pagination.
paginator = Paginator(yourquerysetdata, 20)
page_num = request.data.get('page')
result = yourSerializerName(paginator.get_page(page_num) many=True).data
try:
page = paginator.page(page_num)
except:
page = paginator.page(1)
count = paginator.num_pages
resultobj = paginator.get_page(page_num)
has_prev = resultobj.has_previous()
has_next = resultobj.has_next()
page_range = resultobj.paginator.page_range.stop - 1
if has_prev:
prev_page_no = resultobj.previous_page_number()
else:
prev_page_no = 0
if has_next:
next_page_no = resultobj.next_page_number()
else:
next_page_no = None
context = dict()
context['page'] = page.number
context['page_no'] = count

It is very simple. You just have to modify the query that you are using to fetch the posts.
In the get_context_data() method, replace cat_menu = Category.objects.all() with cat_menu = Category.objects.all().order_by('-post_date')[:15]. This will limit the number of results to 15 most recent objects.
For more understanding, you can take a look at the official Django docs for Limiting QuerySets.

Django pass family in template inside for cycle

In a simple view I pass a family in template like this:
def page(request):
family= Author.objects.all()
return render(request, "myapp/page.html", {'family':family})
and I render in template like this:
{% for item in family %}
{{ item.pk }}
{% endfor %}
But, if I put my family inside a for cycle; for example:
def page(request):
family = []
for i in range(5):
family= Author.objects.filter(name='John')[i]
return render(request, "myapp/page.html", {'family':family})
it not render anything in template...
Any idea?
EDIT 1
I have more users in my app, every user has different blog and every blog has different post...
So when user is logged i need to show his blog and for every blog show last 5 post.
I do:
#login_required
def page(request):
user = request.user.id
numblog = Blog.objects.filter(user_id=user).aggregate(c=Count('id'))
for i in range(numblog['c']):
blogquery = Blog.objects.filter(user_id=user)[i]
postquery = Post.objects.filter(blog_id=blogquery.pk)[:5]
return render(request, "myapp/page.html", {'blogquery ':blogquery,'postquery ':postquery })
expected result in template:
{% for b in blogquery %}
{{ b.name }} ### here name of blog
{% for p in postquery %}
{% if p.blog_id == b.pk %}
{{ p.content }} ### here last 5 post of THAT blog
{% endif %}
{% endfor %}
{% endfor %}
EDIT 2
In a view, if I print result it work but not render in template
#login_required
def page(request):
user = request.user.id
numblog = Blog.objects.filter(user_id=user).aggregate(c=Count('id'))
for i in range(numblog['c']):
blogquery = Blog.objects.filter(user_id=user)[i]
postquery = Post.objects.filter(blog_id=blogquery.pk)[:5]
for p in postquery:
print (blogquery.pk, p.pk)
return render(request, "myapp/page.html", {'blogquery ':blogquery,'postquery ':postquery })

It is surprising how you don't understand that repeatedly assigning to the same variable within a loop will just give you the last value.
But nevertheless, you don't need any of this code. You should just follow the relationship in the template.
#login_required
def page(request):
blogs = Blog.objects.filter(user=user).prefetch_related('post_set')
return render(request, "myapp/page.html", {'blogs ': blogs })
{% for blog in blogs %}
{{ blog.name }}
{% for post in blog.post_set.all|slice:"5" %}
{{ post.content }}
{% endfor %}
{% endfor %}
(You haven't shown your models so I presume the related_name from Blog to Post is called post_set, change as necessary.

UPDATE
That's not correct. You don't need to use for loop. If you need to get the last 5 rows you can do this i.e.:
def page(request):
family= Author.objects.all().order_by('-pk')[:5]
return render(request, "myapp/page.html", {'family':family})
another approach is to limit the results in your template:
{% for item in family %}
{% if forloop.counter < 6 %}
{{ item.pk }}
{% endif %}
{% endfor %}

Search Bar in Django?

I have a bootstrap search bar and I want it to search for a list of all tags in a database. Tags are a like a facebook page or reddit tags.
When I submit my search, I want the URL to include the GET-parameter: ?q="typeword", but the application has to redirect to a new page, and preserve the tags parameter while doing so. How can I do this?
I have tried using GET-request and paginator, but nothing seems to work. I can add a new URL "search/" and then it works, but only with this url.
models.py
class Tag(models.Model):
path = models.CharField(max_length=37,default=0)
name = models.CharField(max_length=35)
description = models.CharField(max_length=200)
image = models.ImageField(default='default.jpg',upload_to='tag_pics')
def __str__(self):
return self.path
views.py
def search(request):
q = request.GET.get('q',None)
items=''
if q is None or q is "":
items = Tag.objects.all()
elif q is not None:
items = Tag.objects.filter(name__contains=q)
paginator = Paginator(items, 3)
page = request.GET.get('page')
items = paginator.get_page(page)
title = "Search"
return render(request, 'blog/search.html',{'items': items, 'title': title})
search.html
{% extends 'blog/base.html' %}
{% block content %}
{% if items %}
<p class="search-count">Found
<strong>
{{ items.paginator.count }}
</strong>
result{{ items.paginator.count|pluralize }}
</p>
{% for i in items %}
{{ i.path }}
{% endfor %}
{% elif request.GET.q %}
<p class="search-no-results">
No results for "<strong>{{ request.GET.q }}"
</p>
{% endif %}
{% endblock %}

Django Pagination "Page not found"

I'm currently having issues with my Django pagination. I have a query set of 9 objects and am paginating one object to a page. So I should have 9 pages total.
Paginator is showing that I have 9 pages, but when I click the "next" page button my (Always on the last/last two pages) my url turns to: http://127.0.0.1:8000/forum/1?page=7
Then I get a 404 page not found error along with "Invalid page (7): That page contains no results"
Here is my class code:
class DirectoryClass(generic.ListView):
template_name = "forum_directory.html"
model = Directory
paginate_by = 1
def get_context_data(self, **kwargs):
context = super(DirectoryClass, self).get_context_data(**kwargs)
directory = Directory.objects.filter(pk=self.kwargs['directory_id'])
context['page'] = 'forum'
context['name'] = directory.first().name
context['user'] = self.request.user
topic_set = directory.first().topic_set.all().order_by('-last_post')
print(topic_set.all())
paginator = Paginator(topic_set, self.paginate_by)
page = self.request.GET.get('page')
try:
topic_set = paginator.page(page)
except PageNotAnInteger:
topic_set = paginator.page(1)
except EmptyPage:
topic_set = paginator.page(paginator.num_pages)
context['topics'] = topic_set
context['page'] = page
return context
Here is the HTML used to change the page:
<div style="width: 1240px; margin: auto; text-align: right;">
{% if topics.has_other_pages %}
<ul class="pagination forum-pagination">
{% if topics.has_previous %}
<li>«</li>
{% else %}
<li class="disabled"><span>«</span></li>
{% endif %}
{% for i in topics.paginator.page_range %}
{% if topics.number == i %}
<li class="active"><span>{{ i }} <span class="sr-only">(current)</span></span></li>
{% else %}
<li>{{ i }}</li>
{% endif %}
{% endfor %}
{% if topics.has_next %}
<li>»</li>
{% else %}
<li class="disabled"><span>»</span></li>
{% endif %}
</ul>
{% endif %}
</div>
Here is the url
path(r'/<int:directory_id>',views.DirectoryClass.as_view(), name='forum_directory'),
What am I doing wrong here?

def get_context_data(self, **kwargs):
context = super(DirectoryClass, self).get_context_data(**kwargs)
context['page'] = 'forum'
context['user'] = self.request.user
return context
def get_queryset(self):
directory = Directory.objects.filter(pk=self.kwargs['directory_id'])
topics = directory.first().topic_set.all().order_by('-last_post')
return topics
use this only in your ListView, as Django provides pagination to all the Class Based View