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How can I simplify this python statements

There's a model represents BBS.
I want to make change the value without update database. because I want to preserve the database value. To be precise at display time, I want it to be displayed as '[collabo]' + article.title this is what I am doing at the moment.
below is combine '[collabo]' and all of title with for loop
for article in articles:
article.title = '[collabo]'+article.title
is there any way to change the title value at one line of code? I don't want to change or update database. Or is there a better way.

If you want to do this in a single database query it's one line longer than what you have now!! but it's far more efficient.
from django.db.models import Value
from django.db.models.functions import Concat
Article.objects.annotate(new_title = Concat(V('[collabo]'),'title')))
The annotate method in the queryset is your friend here (with a little help from Concat and Value)
You could also do this at the template level
articles = Article.objects.all()
render('template.html',{'articles': articles})
And then
{% for article in articles %}
[collabo] {{ article.title }}
{% endfor %}

you may work with methods of the model class to give specific modification you want.
models.py
class Article(models.Model):
# some fields ...
def edited_title(self):
return '[collabo] {}'.format(self.title)
then you can exploit it in the templates with {{article.edited_title}}.

Django: Delete model object using template

I am currently using models to have users enter data, using templates (not admin) that is then stored, at which point the users can then see all the data they entered. I would like to also give users the ability to delete specific entries, this would be done using object ids to identify and delete specific objects.
Here is my views.py:
#login_required(login_url='/login/')
def fav(request):
context = RequestContext(request)
#This returns all of the data the user has entered
favorites_list = StockTickerSymbol.objects.filter(user=request.user).order_by('-added_date')
`
#This is to try to get the ID of every object in favorites_list and append it to a list
for obj in favorites_list:
stock_id = []
stock_id.append(obj.id)
#Here is where the form is processed to save the data the user has entered
if request.method == 'POST':
form = FavoritesForm(request.POST)
if form.is_valid():
stock = form.save(commit=False)
stock.user = request.user
stock.save()
return redirect(fav)
else:
print form.errors
else:
form = FavoritesForm()
context_dict = {'favorites': favorites_list, 'form':form, 'stock_id':stock_id}
return render_to_response('favorites/favorites.html', context_dict, context)
def delete(request, id):
stock_to_delete = get_object_or_404(StockTickerSymbol, pk=id).delete()
return redirect(fav)
Here is my urls.py:
url(r'^favorites/$', views.fav, name='favorites'),
url(r'^add_favorites/$', views.add_fav, name='add favorites'),
url(r'^delete/(?P<id>\d+)/$', views.delete, name='delete')
And this is the part of my template file responsible for deleting
{% for id in stock_id %}
<div align="right">Delete</div>
{% endfor %}
My problem with this code, is that the delete link in my template only gives the first object ID for all the links. For example if there are three submissions for the user, and there id's are 1,2,3. The delete link will read "/delete/1" for all the submissions, thus only allowing users to delete their first submission. Any idea on how I can solve this?

Your problem is here:
for obj in favorites_list:
stock_id = []
stock_id.append(obj.id)
You are reinitializing inside the loop.
Try this
stock_id = []
for obj in favorites_list:
stock_id.append(obj.id)
Note that you can also do:
favorites_list = StockTickerSymbol.objects.filter(user=request.user).order_by('-added_date')
stock_ids = list(facorites_list.values_list('id', flat=True)) #IMO - It is a good idea to name a list with plural for readability
Also, in your delete method - See if the user does have permission to delete the object. If not, anyone can hit this url with some random id and start deleting the objects in the database.
I would start off by adding the login_required decorator, followed by adding a created_by or attaching a group associated with the model, which need to be verified before allowing the user to delete the object.
EDIT
{% for fav in favorite_list %}
<div class="fav">
{{fav.name}}
</div>
Delete me
{% endfor %}
Now you can do away with the id list.

Using one model to filter another model in Django

I'm trying to access the information in my gadb_action model based on the action_ids in my gadb_vote model. I'm initially only getting the information for a particular legislator and then attempting to get the bills associated with the actions that legislator has voted on.
Right now, my action_list is only storing action_ids, but not the related information from the gadb_action model that I want to use in my template.
What is the best way to store that information outside of the for loop to be accessed by the template? Is there a way to write to an empty QuerySet?
Thanks in advance for any and all help!
view
def each_member(request,legislator_id):
each_member = get_object_or_404(gadb_legislator, legislator_id=legislator_id)
each_vote = gadb_vote.objects.filter(legislator_id=legislator_id)
action_list = []
for i in each_vote:
action = gadb_action.objects.filter(action_id=i.action_id)
action_list.append(action)
context = {
'each_member': each_member,
'each_vote': each_vote,
'action_list': action_list
}
return render(request, "eachmember.html", context)
models
class gadb_action(models.Model):
action_id = models.IntegerField(unique=False, max_length=4, primary_key=True)
bill_id = models.IntegerField(unique=False, max_length=12)
class gadb_vote(models.Model):
vote_id = models.IntegerField(unique=False, max_length=11,primary_key=True)
legislator_id = models.IntegerField(unique=False, max_length=11)
action_id = models.IntegerField(unique=False, max_length=11)
template
{% for i in action_list %}
{{i.bill_id}}
{{i.action_id}}
{% endfor %}

Your models are broken.
For a start, although it's not directly related to the question, you need to define your primary keys as AutoFields so that they are autoincremented every time a new entity is added. Otherwise you'll get all sorts of errors when you save a new row. (Even better, don't define the PK at all, and let Django add it automatically.)
Secondly, as lalo says, you should have ForeignKeys from Action to Bill, and from Vote to Action and Vote to Legislator. That way you can get the relevant information with a single query, and follow the foreign keys as required in your template.
(Also, Django already includes the app name in the underlying table name: no need to prefix everything with 'gadb'.)
class Action(models.Model):
bill = models.ForeignKey(Bill)
class Vote(models.Model):
legislator = models.ForeignKey(Legislator)
action = models.ForeignKey(Action)
View:
def each_member(request,legislator_id):
actions = Action.objects.filter(vote__legislator_id=legislator_id)
return render(request, "eachmember.html", {'action_list': actions})
Template:
{% for action in actions %}
{{ action.bill.name }}
{{ action.someotherfield }}
{% endfor %}

How to Embed a Template Variable Inside a Hyperlink - Django Template

I am brand new to web development, Django, python, html, etc. I have a basic Django app that displays a list of publication titles that have been entered into the database. This works fine.
I now want to make it so that each publication title is a link that - when clicked on - renders another template with the details of the publication that was clicked. So far, I know how to get the publication link to render a template, but I am trying to figure out how to pass in the publication title to the hyperlink so that the data that is rendered in the details template will be specific to the title that was chosen.
Here is what I have in my publication template which displays all the publications (it is incorrect, but hopefully it clarifies what I am trying to do):
<html>
<head><title>Publications</title></head>
<body>
<h1>Publications</h1>
<ul>
{% for publication in publication_list %}
<li><strong>{{ publication.title}}</strong></li>
{% endfor %}
</ul>
</body>
</html>
For the sake of context, the url pattern that handles this is:
url(r'^(?P<detail_type>\w+)/(?P<link_item>\w+)/detail$', get_details)
And the view function is:
// note: I may have some of the logic/syntax wrong here, but this is the basic idea
def get_details(request, detail_type=None, link_item=None):
if detail_type == "publications":
publication = Publication.objects.filter(title__iexact=link_item)
return render(request, 'publication_detail.html', {'detail_type' : detail_type, 'publication' : publication})
elif ....
Like I said, I am very much a beginner so if I am approaching this in wrong way, any suggestions or resources are appreciated. Thanks.

If you use named url patterns you can easily do this with the url template tag.
urls.py
url(r'^(?P<detail_type>\w+)/(?P<link_item>\w+)/detail$', get_details, name='details')
template
{% url 'details' 'publications' publication.title %}
I hope you know about SlugField too, it is much better for urls than a normal CharField.
An alternative:
urls.py
url(r'^(?P<detail_type>\w+)/(?P<pk>\w+)/detail$', get_details, name='details')
template
{% url 'details' 'publications' publication.pk %}
views.py
def get_details(request, detail_type=None, pk=None):
if detail_type == "publications":
publication = Publication.objects.get(pk=pk)
return render(request, 'publication_detail.html', {'detail_type' : detail_type, 'publication' : publication})
elif ....
This uses the primary key of the entry instead of the title. If you want to have a url with the title in it you will want to add and use a SlugField on your model.

This looks pretty good to me, although you may want to use get as opposed to filter in your view function if all the publication titles are unique and you want to pass an instance of Publication rather than a queryset (containing one item) into the detail template. This would throw an error of there were 0 or >1 matches, but it sounds like that's probably the behavior you'd want
However, I'm not sure what it is that you're missing here. What does publication_detail.html look like? You should have essentially everything you need in the above code to render the details, assuming they're all contained in the relevant Publication instance.

Django History for Custom Dashboard

I have decided to use Django-Simple-History for building a history of my models. In turn using that to build the dashboard. I have run into a bit of a snag though. I'm trying to output [User] [added,changed, deleted] [object] on/at [time] but I can't figure it out for the life of me.
So far I am able to display the historical record on the template but I can't access anything else, am I missing something?
I was hoping someone with knowledge of Simple History can help, since I couldn't get a hold of the author.
Here is the code snippets I have so far.
Models.py
from simple_history.models import HistoricalRecords
class Project(django.db.models.Model):
...
history = HistoricalRecords()
Views.py
#login_required
def addTMProject(request):
user = request.user
if request.method == 'POST':
form = TimeMaterialsForm(request.POST)
if form.is_valid():
project = form.save(commit=False)
project.created_by = request.user
today = datetime.date.today()
project.pre_quote = "%s-" % (str(today.year)[2:4])
project.quote = Project.objects.latest().quote+1
project.save()
project.history.all()
...
And I have also passed it on my dashboard/views.py so I have access to it.
#login_required
def view_dash(request):
today = datetime.date.today()
user = request.user
proj_perm = user.has_perm('project.add_project')
project = Project.objects.all().order_by('-proj_name')
query = Project.objects.all().order_by('-id')[:5]
que_quotes = Project.objects.filter(status__value__exact = 'Quote')
expired = FollowUp.objects.filter(next_followup__lte=today).order_by('next_followup').filter(archived=False)
log = LogEntry.objects.select_related().all().order_by("-id")
hist = Project.history.all()
return render_to_response('dashboard/home.html', {'user': user, 'project': project, 'query':query, 'que_quotes':que_quotes, 'expired':expired,
'proj_perm':proj_perm, 'log': log, 'hist':hist,}, context_instance=RequestContext(request))
And finally a snippet from my template. As it is right now, the {{ h }} shows "Testing Simple Records as of 2011-04-29 10:43:57" on the template
home.html
{% if user.is_authenticated %}
<div id="large_box">
<h5>Activity</h5>
{% for h in hist %}
<ul>
<li>{{ h }}</li>
</ul>
{% endfor %}
If anyone could help or point me to some more in depth documentation, then that would be great!
Thanks everyone!

Django-Simple-History simply creates a model (and associated database table) that mirrors the object you tie it to and adds four additional fields: history_id, history_date, history_type, and history_object.
history_id: standard primary key
history_date: datetime for when the change occurred
history_type: one of +, ~, -. (+ means added, ~ means changed, and - means deleted)
history_object: representation of the model that history is being stored for
So, at most basic level, you can roughly get "[added,changed, deleted] [object] on/at [time]" in your output, using something to the effect of:
{{ h.history_type }} {{ h.history_object }} on/at {{ h.history_date }}
You'll probably want to create template tag or something to convert the +, ~, and - to the more understandable, 'Created', 'Changed', 'Deleted'. {{ h.history_object }} should return the object's __unicode__, I'm assuming, so you might need to make some modifications there or return something like {{ h.history_object.__class__ }} or {{ h.history_object._meta.verbose_name }}, instead. (Not sure if those will actually work in practice though.) And, of course, you can apply the date filter to {{ h.history_date }} to make it any format you want.
Getting the user is more difficult. Django-Simple-History doesn't seem to store this data, so there's no record of what user made the modification. However, since it basically duplicates the object as it existed, you could probably get away with adding a modified_by field to your model and filling that with request.user pre-save. Then, when Django-Simple-History does its thing, that field would be copied over like the rest and be available via {{ h.modified_by }}.

I'm assuming that the only problem you're having is with the displaying of the historical data and not the actual saving portion of it.
I'm not sure what fields you have in your Project model, but it looks like the history field is treated like a foreign key field. This foreign key's table contains the same fields that your Project model does. So, if you want to access the fields you'd have to do something like this in your template:
...
{% for h in hist %}
<ul>
<li>{{h.field1}} {{h.field2}} {{h.field3}} on {{h.field4}}</li>
</ul>
{% endfor %}
...
I found this page (http://qr7.com/2010/10/django-simple-history-ftw/) which was quite helpful, but you'll have to play around with the history field names. I wasn't quite sure what they actually were.
Hope that helps.