Re: [Tutor] model methods in Django
On Sun, May 19, 2013 at 10:49 AM, Matthew Ngaha wrote: > On Sun, May 19, 2013 at 3:34 PM, Steven D'Aprano wrote: >> Matthew, who are you quoting? Your email program should automatically insert >> an attribution line, such as the one just below. Without that attribution >> line, it is hard to follow the conversation, as we can't tell who you are >> quoting. > > ok thanks i didnt think about that. I was quoting eryksun. I'll > includethat line from now on I think this was in reference to your reply to John Steedman. Here's the archive thread (based on the "In-Reply-To" header field): http://mail.python.org/pipermail/tutor/2013-May/thread.html#95521 ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] model methods in Django
On Sun, May 19, 2013 at 3:34 PM, Steven D'Aprano wrote: > Matthew, who are you quoting? Your email program should automatically insert > an attribution line, such as the one just below. Without that attribution > line, it is hard to follow the conversation, as we can't tell who you are > quoting. > > On 20/05/13 00:23, Matthew Ngaha wrote: ok thanks i didnt think about that. I was quoting eryksun. I'll includethat line from now on ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] model methods in Django
Matthew, who are you quoting? Your email program should automatically insert an attribution line, such as the one just below. Without that attribution line, it is hard to follow the conversation, as we can't tell who you are quoting. On 20/05/13 00:23, Matthew Ngaha wrote: class Poll(models.Model): [...] -- Steven ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] model methods in Django
> options.py is the biggest module in the admin package. The link I > posted is to the get_actions method of ModelAdmin. In the tutorial, > PollAdmin extends this class. > oh ok thanks, yes i will definately look through it > I'm not coming from any framework. My knowledge of web development is > scattered from bits learned here and there, out of curiosity rather > than necessity. With Python 3 you're a bit limited, but you still have > options. Obviously there's Django -- arguably the most popular, > batteries-included framework. Pyramid is a leaner alternative. Bottle > and CherryPy (also a WSGI server) are micro frameworks. There's also > Tornado if you want an asynchronous framework based on callbacks and > coroutines. As there are a lot more guides for Django i think i will stick with it rather than Pyramid. Maybe after ive learnt it well i can pick up Cherrypy as i like the sounds of a small framework with a server. But Django will be my main focus. Thanks for detailing the options for Python 3 ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] model methods in Django
> class Poll(models.Model):
>
> question = models.CharField(max_length=200)
> pub_date = models.DateTimeField('date published')
>
>
>
> def was_published_recently(self):
> return self.pub_date >= timezone.now() - datetime.timedelta(days=1)
>
> #
>
>
> was_published_recently.admin_order_field = 'pub_date'
> was_published_recently.boolean = True
> was_published_recently.short_description = 'Published recently?'
>
>
> Source:
> https://docs.djangoproject.com/en/dev/intro/tutorial01/
> https://docs.djangoproject.com/en/dev/intro/tutorial02/
>
>
> I find the Django (and this fragment) very elegant UP TO the comment.
>
is the dislike after the comment more to do with the python code
rather than django itself?
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Re: [Tutor] model methods in Django
On Sun, May 19, 2013 at 7:20 AM, Matthew Ngaha wrote: > Thanks that does clear it up. Also thats a huge script you linked, can options.py is the biggest module in the admin package. The link I posted is to the get_actions method of ModelAdmin. In the tutorial, PollAdmin extends this class. > i ask which framework you're coming from, and why you have decided to > try out django? When i asked around, people's opinions of it weren't > good and i was recommended to try flask but as i only use Python 3, i > won't be able to use Flask. I'm not coming from any framework. My knowledge of web development is scattered from bits learned here and there, out of curiosity rather than necessity. With Python 3 you're a bit limited, but you still have options. Obviously there's Django -- arguably the most popular, batteries-included framework. Pyramid is a leaner alternative. Bottle and CherryPy (also a WSGI server) are micro frameworks. There's also Tornado if you want an asynchronous framework based on callbacks and coroutines. ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] model methods in Django
For the benefit of others,I believe the full class (from the Django
Tutorial) is
class Poll(models.Model):
question = models.CharField(max_length=200)
pub_date = models.DateTimeField('date published')
def was_published_recently(self):
return self.pub_date >= timezone.now() - datetime.timedelta(days=1)
#
was_published_recently.admin_order_field = 'pub_date'
was_published_recently.boolean = True
was_published_recently.short_description = 'Published recently?'
Source:
https://docs.djangoproject.com/en/dev/intro/tutorial01/
https://docs.djangoproject.com/en/dev/intro/tutorial02/
I find the Django (and this fragment) very elegant UP TO the comment.
On Sat, May 18, 2013 at 8:16 PM, Matthew Ngaha wrote:
> im following the official docs and after learning Python im sure of
> how methods work, but the model example on the beginners guide has me
> really confused.
>
> The model definition is omitted but can anyone explain how this methed
> (was_published_recently) is given these attributes:
>
> class Poll(models.Model):
> # ...
> def was_published_recently(self):
> return self.pub_date >= timezone.now() - datetime.timedelta(days=1)
> was_published_recently.admin_order_field = 'pub_date'
> was_published_recently.boolean = True
> was_published_recently.short_description = 'Published recently?'
>
> are the names of the attributes already attached to these
> functions/methods, or are they being created on the fly with whatever
> name you want? As i am unable to comprehend what is going on, i dont
> really have a clue as to what each definition is doing and how it
> affects the model, even after reading this section of the docs over
> and over again im still lost.
> ___
> Tutor maillist - Tutor@python.org
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Re: [Tutor] model methods in Django
> The default description is the name with underscores removed, unless > you set a custom description in the function's "short_description" > attribute. I'm not experienced with Django, so I can't ramble off lots > of examples, but hopefully you get the gist. Thanks that does clear it up. Also thats a huge script you linked, can i ask which framework you're coming from, and why you have decided to try out django? When i asked around, people's opinions of it weren't good and i was recommended to try flask but as i only use Python 3, i won't be able to use Flask. ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] model methods in Django
On Sun, May 19, 2013 at 6:35 AM, Matthew Ngaha wrote:
>
> if you look at the diagram under that function, why is the value of
> "was_published_recently.short_description" the title of that field?
> replacing the old title? is a "short_desccription" attribute set
> somewhere in django being inactive, but once you make use of this
> attribute(or keyword), whatever the value is automatically becomes the
> field title? is it the same for boolean being the value of the field
> with the checked or unchecked symbol?
For example, see line 586 in admin/options.py:
https://github.com/django/django/blob/1.5.1/django/contrib/admin/options.py#L586
# Gather actions from the admin site first
for (name, func) in self.admin_site.actions:
description = getattr(func, 'short_description',
name.replace('_', ' '))
actions.append((func, name, description))
The default description is the name with underscores removed, unless
you set a custom description in the function's "short_description"
attribute. I'm not experienced with Django, so I can't ramble off lots
of examples, but hopefully you get the gist.
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Re: [Tutor] model methods in Django
Thanks guys i had no idea about these method attributes and also these underlying oop __objects__ @ eryksun i understand your explanation, im still having trouble figuring out how django is being used in the tutorial. class Poll(models.Model): # ... def was_published_recently(self): return self.pub_date >= timezone.now() - datetime.timedelta(days=1) was_published_recently.admin_order_field = 'pub_date' was_published_recently.boolean = True was_published_recently.short_description = 'Published recently?' list_filter = ['pub_date'] search_fields = ['question'] date_hierarchy = 'pub_date' if you look at the diagram under that function, why is the value of "was_published_recently.short_description" the title of that field? replacing the old title? is a "short_desccription" attribute set somewhere in django being inactive, but once you make use of this attribute(or keyword), whatever the value is automatically becomes the field title? is it the same for boolean being the value of the field with the checked or unchecked symbol? ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] model methods in Django
On Sat, May 18, 2013 at 10:22 PM, Dave Angel wrote: > The pub_date is probably an instance attribute of either the Poll class or > the models.Model class. It should probably be defined in the appropriate > __init__ method. In any case it's not a method attribute. Django uses function attributes as metadata. The names "boolean" and "short_description" are self-documenting. "admin_order_field" is explained here: https://docs.djangoproject.com/en/dev/ref/contrib/admin/ #django.contrib.admin.ModelAdmin.list_display Usually, elements of list_display that aren’t actual database fields can’t be used in sorting (because Django does all the sorting at the database level). However, if an element of list_display represents a certain database field, you can indicate this fact by setting the admin_order_field attribute of the item. The Poll model is part of the tutorial, "Writing your first Django app": https://docs.djangoproject.com/en/1.5/intro The function attributes are added in "Customize the admin change list", in part 2. > Perhaps you didn't realize that a function can have attributes, and that > they can be added to the function at any time after the function is created. > Being a method doesn't change that. In a class definition, from a conceptual point of view, you're adding a 'method'. But technically it's a function object. When accessed as an attribute, the function's __get__ descriptor is used to create a method on the fly. The instancemethod type has a custom __getattribute__ that first checks the method object's attributes such as __self__. If the lookup on the method object fails, it proxies the __getattribute__ of the wrapped __func__. For example: class Spam(object): def __repr__(self): return 'eggs' >>> meth = Spam().__repr__ >>> type(meth) >>> meth.__self__ eggs A method doesn't have a __dict__ for setting dynamic attributes: >>> meth.boolean = False Traceback (most recent call last): File "", line 1, in AttributeError: 'instancemethod' object has no attribute 'boolean' But you can set attributes on the underlying function object: >>> type(meth.__func__) >>> meth.__func__.boolean = False The method will proxy them: >>> meth.boolean False But not for assignment: >>> meth.boolean = True Traceback (most recent call last): File "", line 1, in AttributeError: 'instancemethod' object has no attribute 'boolean' ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] model methods in Django
On 05/18/2013 03:16 PM, Matthew Ngaha wrote: im following the official docs and after learning Python im sure of how methods work, but the model example on the beginners guide which official docs? URLs please? which beginners guide? URL please? has me really confused. I don't know Django, so if this is really Django specific, I can't help. The model definition is omitted but can anyone explain how this methed (was_published_recently) is given these attributes: Which attributes are you confused about? The admin_order_field, boolean, ande short_description attributes of the method are bound in class code, immediately after the method is defined. The pub_date is probably an instance attribute of either the Poll class or the models.Model class. It should probably be defined in the appropriate __init__ method. In any case it's not a method attribute. class Poll(models.Model): # ... def was_published_recently(self): return self.pub_date >= timezone.now() - datetime.timedelta(days=1) was_published_recently.admin_order_field = 'pub_date' was_published_recently.boolean = True was_published_recently.short_description = 'Published recently?' are the names of the attributes already attached to these functions/methods, or are they being created on the fly with whatever name you want? As i am unable to comprehend what is going on, i dont really have a clue as to what each definition is doing and how it affects the model, even after reading this section of the docs over and over again im still lost. This fragment isn't big enough for much else to be told. But I don't really understand what aspect is confusing you. Perhaps you didn't realize that a function can have attributes, and that they can be added to the function at any time after the function is created. Being a method doesn't change that. -- DaveA ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
[Tutor] model methods in Django
im following the official docs and after learning Python im sure of how methods work, but the model example on the beginners guide has me really confused. The model definition is omitted but can anyone explain how this methed (was_published_recently) is given these attributes: class Poll(models.Model): # ... def was_published_recently(self): return self.pub_date >= timezone.now() - datetime.timedelta(days=1) was_published_recently.admin_order_field = 'pub_date' was_published_recently.boolean = True was_published_recently.short_description = 'Published recently?' are the names of the attributes already attached to these functions/methods, or are they being created on the fly with whatever name you want? As i am unable to comprehend what is going on, i dont really have a clue as to what each definition is doing and how it affects the model, even after reading this section of the docs over and over again im still lost. ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
