Django Web Framework: The 'D' is silent dumbass

The Something Awful Forums > Discussion > Serious Hardware/Software Crap > The Cavern of COBOL > Django Web Framework: The 'D' is silent dumbass

«‹›122 »

MonkeyMaker: May 22, 2006; What's your poison, sir?

fletcher posted:

From the Model.clean docs:

So I've got:

Python code:

class Person(models.Model):
    first_name = models.CharField(max_length=100)
    last_name = models.CharField(max_length=100)
    full_name = models.CharField(max_length=201)

    def clean(self):
        self.full_name = self.first_name + ' ' + self.last_name

Then in the admin console:

code:

>>> joe_schmoe = Person.objects.get(full_name='Joe Schmoe')
>>> joe_schmoe.first_name = 'Joseph'
>>> joe_schmoe.save()
>>> Person.objects.get(full_name='Joseph Schmoe')
DoesNotExist: Person matching query does not exist.

What's the point of using a Model.clean() override to set full_name if Model.save() doesn't invoke it?

Model.clean() is kind of a lovely little snippet. It only gets called by ModelForm.clean() and, even then, isn't super-reliable.

If you want to custom calculate a field on a model, do it in the save() method.

# ? Apr 5, 2014 01:36

Adbot: ADBOT LOVES YOU

# ? May 31, 2024 08:27

Smarmy Coworker: May 10, 2008; by XyloJW

Django friends itt:
what is best in life, Django or Python-Twisted? I've never Django'd before.

# ? Apr 6, 2014 17:33

Tavistock: Oct 30, 2010

They do different things. Ones for doing async web server while django is a framework for creating websites. Django uses at a lower level a web server to handle requests but mostly that sort of stuff is abstracted away from a django user. The best way to get a hang of what I mean is to go and do the poll tutorial on the django website. But yea django is best in life but so is python-twisted and;

# ? Apr 7, 2014 20:56

Smarmy Coworker: May 10, 2008; by XyloJW

okay, so if I didn't really want to get heavy into async web stuff which I did on my job, for a personal website, I should maybe use Django?

# ? Apr 7, 2014 23:45

Thermopyle: Jul 1, 2003; ...the stupid are cocksure while the intelligent are full of doubt. �Bertrand Russell

Smarmy Coworker posted:

okay, so if I didn't really want to get heavy into async web stuff which I did on my job, for a personal website, I should maybe use Django?

If it needs a database, sure.

# ? Apr 7, 2014 23:52

Smarmy Coworker: May 10, 2008; by XyloJW

golden

# ? Apr 8, 2014 19:07

Blinkz0rz: May 27, 2001; MY CONTEMPT FOR MY OWN EMPLOYEES IS ONLY MATCHED BY MY LOVE FOR TOM BRADY'S SWEATY MAGA BALLS

Hey folks, I'm having a weird issue that I was hoping for some help with.

I have a model with clean() and validate_unique(). When the model is invalid I raise a ValidationError in these methods as per the documentation.

However, when I create a model that's invalid from the admin panel, I get

code:

'ValidationError' object has no attribute 'error_dict'

and the model doesn't get saved.

Does anyone know how to resolve this issue?

# ? Apr 8, 2014 19:29

Yay: Aug 4, 2007

MonkeyMaker posted:

Model.clean() is kind of a lovely little snippet. It only gets called by ModelForm.clean() and, even then, isn't super-reliable.

its only really lovely* because 5 versions later, it's still not called by default (nor is full_clean), presumably still in the misguided name of backwards compatibility.

As someone who does call full_clean mostly, I'd be keen to know in what way you're suggesting it's not reliable, as it's not something I've ever knowingly come across.

* actually, model validation is also lovely because it has a different API to forms. An API which has remained stable and flexible for ... 7 versions?

# ? Apr 9, 2014 17:55

Ahz: Jun 17, 2001; PUT MY CART BACK? I'M BETTER THAN THAT AND YOU! WHERE IS MY BUTLER?!

Does anyone know the best go-to library or whatever to generate custom QR codes?

I'm looking to generate and then store the GIF or whatever they create as a binary in postgres.

# ? Apr 10, 2014 00:32

fletcher: Jun 27, 2003; ken park is my favorite movie; Cybernetic Crumb

Ahz posted:

Does anyone know the best go-to library or whatever to generate custom QR codes?

I'm looking to generate and then store the GIF or whatever they create as a binary in postgres.

Out of curiosity, what do you want to use the QR codes for? I only ask because I've never seen somebody point their phone at one before.

PNG (or even SVG?) would be a much better format for QR codes than GIF I would think.

There seems to be no shortage of libraries for QR codes on PyPi:

https://pypi.python.org/pypi/qrcode
https://pypi.python.org/pypi/django-qrcode

# ? Apr 10, 2014 00:55

Ahz: Jun 17, 2001; PUT MY CART BACK? I'M BETTER THAN THAT AND YOU! WHERE IS MY BUTLER?!

Yeah I found those libraries, they seem to work fine, thanks.

They're a bit of a fad, but I don't think they're going away and only going to become more ubiquitous as they become a more accepted standard for mobile input. Ironically in my quest to find a good qrcode generating library for python, I decided to just do QR generation on the fly on iOS/Android itself instead of server-side.

# ? Apr 10, 2014 03:17

Blinkz0rz: May 27, 2001; MY CONTEMPT FOR MY OWN EMPLOYEES IS ONLY MATCHED BY MY LOVE FOR TOM BRADY'S SWEATY MAGA BALLS

Yay posted:

* actually, model validation is also lovely because it has a different API to forms. An API which has remained stable and flexible for ... 7 versions?

Yeah, what's the deal with this? You'd think more effort would be put into something that promotes DRY principles.

Basically I don't want to write separate form validation for my admin form and my application form and the fact that it's like pulling teeth is frustrating to say the least.

# ? Apr 10, 2014 12:01

MonkeyMaker: May 22, 2006; What's your poison, sir?

Blinkz0rz posted:

Yeah, what's the deal with this? You'd think more effort would be put into something that promotes DRY principles.

Basically I don't want to write separate form validation for my admin form and my application form and the fact that it's like pulling teeth is frustrating to say the least.

Just make your Model.save() check for Model.clean() before it saves, obv.

(I've, sadly, done that before)

---

Also, I gave a tutorial yesterday at PyCon (if you're here, say hi). If any of you want the book I wrote for it, it's here as a PDF or here as HTML

# ? Apr 10, 2014 15:33

Blinkz0rz: May 27, 2001; MY CONTEMPT FOR MY OWN EMPLOYEES IS ONLY MATCHED BY MY LOVE FOR TOM BRADY'S SWEATY MAGA BALLS

MonkeyMaker posted:

Just make your Model.save() check for Model.clean() before it saves, obv.

(I've, sadly, done that before)

To be honest, the issue I'm running into is raising multiple ValidationError exceptions from the model.clean() and model.validate_unique() methods.

You'd think the error dictionary would work correctly, but it seems like there's a minor difference in the way the model instance is handled when it's being returned from model validation versus form validation.

Any thoughts on how to handle that? I was thinking I could write stubs for the form that implement full_clean() and then handle the exceptions when they bubble up, but I really do want to adhere to DRY.

# ? Apr 10, 2014 20:50

more like dICK: Feb 15, 2010; This is inevitable.

MonkeyMaker posted:

Just make your Model.save() check for Model.clean() before it saves, obv.

(I've, sadly, done that before)

---

Also, I gave a tutorial yesterday at PyCon (if you're here, say hi). If any of you want the book I wrote for it, it's here as a PDF or here as HTML

I'm at Pycon! I'll say hello awkwardly if I see you.

# ? Apr 11, 2014 00:46

MonkeyMaker: May 22, 2006; What's your poison, sir?

blinkz0rz posted:

To be honest, the issue I'm running into is raising multiple ValidationError exceptions from the model.clean() and model.validate_unique() methods.

You'd think the error dictionary would work correctly, but it seems like there's a minor difference in the way the model instance is handled when it's being returned from model validation versus form validation.

Any thoughts on how to handle that? I was thinking I could write stubs for the form that implement full_clean() and then handle the exceptions when they bubble up, but I really do want to adhere to DRY.

Not really. I don't think I've ever really used Model.validate_unique().

There isn't a model instance being returned from form validation, though. It's actually a ModelForm instance which is "saved" before the model is written to the db itself. It's a weird process but seems to work.

# ? Apr 12, 2014 20:07

Blinkz0rz: May 27, 2001; MY CONTEMPT FOR MY OWN EMPLOYEES IS ONLY MATCHED BY MY LOVE FOR TOM BRADY'S SWEATY MAGA BALLS

I ended up moving my uniqueness test (Model.validate_unique()) into clean() even though the docs say I should separate them. Everything works now. Weird that raising multiple ValidationError exceptions in separate validation methods would blow up so spectacularly.

# ? Apr 13, 2014 01:38

MonkeyMaker: May 22, 2006; What's your poison, sir?

If you missed PyCon 2014 (or just the tutorials or whatever), lots of the videos are online. Two of the Django tutorials:

Django for Web Designers and Front End Developers by Tracy Osborn

Getting Started with Django: A Crash Course by me.

# ? Apr 14, 2014 12:53

Pollyanna: Mar 5, 2005; Milk's on them.

I'm going to cry. How do I get a traceback in Foreman/Heroku logs for Django? I'm getting a Server Error 500 in Foreman when everything works perfectly on a local server.
I can't figure out why it's breaking without knowing what's erroring out. Unfortunately, all I get from Foreman is:

code:

17:45:34 web.1  | started with pid 79852
17:45:34 web.1  | 2014-04-15 17:45:34 [79852] [INFO] Starting gunicorn 18.0
17:45:34 web.1  | 2014-04-15 17:45:34 [79852] [INFO] Listening at: [url]http://0.0.0.0:5000[/url] (79852)
17:45:34 web.1  | 2014-04-15 17:45:34 [79852] [INFO] Using worker: sync
17:45:34 web.1  | 2014-04-15 17:45:34 [79855] [INFO] Booting worker with pid: 79855

and nothing else. Heroku logs aren't much help either:

code:

request_id=ef7d2d17-4b62-4118-9bd4-2d8cd2d9ba56 fwd="98.231.79.0" dyno=web.1 connect=12ms service=25ms status=200 bytes=1438
2014-04-15T21:32:30.335248+00:00 heroku[router]: at=info method=POST path=/hangman/login/ host=app-tracker.herokuapp.com request_id=27ff9f9b-9574-4379-9705-cc3957971555 fwd="98.231.79.0" dyno=web.1 connect=65ms service=275ms status=200 bytes=1454
2014-04-15T21:32:30.303270+00:00 app[web.1]: <ul class="errorlist"><li>__all__<ul class="errorlist"><li>Please enter a correct username and password. Note that both fields may be case-sensitive.</li></ul></li></ul>
2014-04-15T21:32:33.135941+00:00 heroku[router]: at=info method=POST path=/hangman/login/ host=app-tracker.herokuapp.com request_id=e23d79e1-ab2e-4a0f-8c9c-fd79190b5105 fwd="98.231.79.0" dyno=web.1 connect=11ms service=222ms status=302 bytes=521
2014-04-15T21:32:33.614881+00:00 heroku[router]: at=info method=GET path=/hangman/ host=app-tracker.herokuapp.com request_id=9e069246-6fcc-494a-887f-d6c27d3a3b4e fwd="98.231.79.0" dyno=web.1 connect=14ms service=304ms status=500 bytes=251

Is there a way to get a real trace stack from Foreman? Cause I need to know why this isn't working.

# ? Apr 15, 2014 22:54

fletcher: Jun 27, 2003; ken park is my favorite movie; Cybernetic Crumb

What does your logging config look like in Django?

I have this in mine and it sends me an email with the full stack trace and all kinds of useful information if somebody hits a 500 error:

code:

LOGGING = {
    'version': 1,
    'disable_existing_loggers': False,
    'filters': {
        'require_debug_false': {
            '()': 'django.utils.log.RequireDebugFalse'
        }
    },
    'handlers': {
        'mail_admins': {
            'level': 'ERROR',
            'filters': ['require_debug_false'],
            'class': 'django.utils.log.AdminEmailHandler'
        }
    },
    'loggers': {
        'django.request': {
            'handlers': ['mail_admins'],
            'level': 'ERROR',
            'propagate': True,
        },
    }
}

# ? Apr 15, 2014 23:03

Pollyanna: Mar 5, 2005; Milk's on them.

Um, I don't. How do I use that?

# ? Apr 15, 2014 23:54

fletcher: Jun 27, 2003; ken park is my favorite movie; Cybernetic Crumb

Put it in your settings.py file

# ? Apr 16, 2014 00:04

Pollyanna: Mar 5, 2005; Milk's on them.

So this sends you an email, correct? The documentation mentions something about adding logger functions to the views. Do I need to include that as well, or does Django automatically handle stacktraces and email them?

Also, I assume it won't send an email from Foreman, and only off of the herokuapp server?

# ? Apr 16, 2014 00:16

fletcher: Jun 27, 2003; ken park is my favorite movie; Cybernetic Crumb

Aw crap I thought it would be easy to send email on Heroku but apparently it's not, you have to use a third party SMTP provider: https://devcenter.heroku.com/articles/smtp

Django can then be configured to use that third party SMTP server: https://docs.djangoproject.com/en/dev/topics/email/

So maybe not the route you want to go down right now if we're just trying to debug this 500 error. Regardless, to answer your logger functions in the views question, you don't have to do that stuff for the email alerts I was talking about.

I'm actually not familiar with foreman at all, so not sure on that one. Sorry

I think your solution is probably in the logging configuration though.

# ? Apr 16, 2014 00:40

Pollyanna: Mar 5, 2005; Milk's on them.

Don't worry about it, I figured I can store the log as a file. I managed to track it down to a South fuckup :argh:

I ended up wiping the database and starting over, but hooray, it works! Thanks a bunch.

# ? Apr 16, 2014 01:06

Thermopyle: Jul 1, 2003; ...the stupid are cocksure while the intelligent are full of doubt. �Bertrand Russell

FYI, it's really easy to set up django send grid on heroku to send emails. Just google it and you'll be running all quick like.

# ? Apr 16, 2014 04:05

fletcher: Jun 27, 2003; ken park is my favorite movie; Cybernetic Crumb

Python code:

def generate_photo_filename(instance, filename):
    image = Image.open(???)
    ext = image.format
    filename = '%s.%s' % (uuid.uuid4(), ext)
    return os.path.join('myproject/photos', filename)


class Person(models.Model):
    name = models.CharField(max_length=75)
    profile_photo = models.ImageField(upload_to=generate_photo_filename)
    cover_photo = models.ImageField(upload_to=generate_photo_filename)

I wanted to handle the scenario where somebody uploads whatever.jpg but it's actually a gif file.

What goes in the question marks? How does generate_photo_filename know if it's handling profile_photo or cover_photo? I could just make separate functions for upload_to, wondering if there is a better way to handle this though.

edit: and I suppose .jpg is just slightly more correct than .jpeg, but whatever we can ignore that for now

fletcher fucked around with this message at 02:47 on Apr 17, 2014

# ? Apr 17, 2014 02:43

raymond: Mar 20, 2004

fletcher posted:

wondering if there is a better way to handle this though

I've not used it but this is what I would do:

https://github.com/iserko/django-storages/blob/master/storages/backends/image.py

You can use custom storage objects like:

Python code:

image_storage = ImageStorage(location='/myproject')

class Person(models.Model):
    name = models.CharField(max_length=75)
    profile_photo = models.ImageField(upload_to='photos/people', storage=image_storage)
    cover_photo = models.ImageField(upload_to='photos/people', storage=image_storage)

raymond fucked around with this message at 16:01 on Apr 17, 2014

# ? Apr 17, 2014 08:19

supermikhail: Nov 17, 2012; "It's video games, Scully."
Video games?"
"He enlists the help of strangers to make his perfect video game. When he gets bored of an idea, he murders them and moves on to the next, learning nothing in the process."
"Hmm... interesting."

What's the best way to create this setup:

Entry - rating - User?

Entry has ratings, User also has ratings that s/he has made of entries. (Also should I extend the base User class?) Currently I have a Rating class that has User and Entry as ForeignKeys, but I'm not sure how to handle Entry. Should it have a ManyToManyField "ratings" variable (even though a Rating can belong only to one Entry)? Also each Rating object can be made only by a single User.

I'm sure this stuff is handled daily by experienced coders, so how? (The purpose of the arrangement is obviously to ensure that one user gets one vote/rating.)

# ? Apr 20, 2014 20:13

Pollyanna: Mar 5, 2005; Milk's on them.

Each Rating belongs to one User and to one Entry, I suppose? Each Entry and each User can Have Many Ratings, but each Rating has one associated Entry and one associated User. So the Rating would have a Foreign Key to a user and a Foreign Key to an Entry, and both Entries and Users have one-to-many fields for Ratings.

# ? Apr 20, 2014 21:01

supermikhail: Nov 17, 2012; "It's video games, Scully."
Video games?"
"He enlists the help of strangers to make his perfect video game. When he gets bored of an idea, he murders them and moves on to the next, learning nothing in the process."
"Hmm... interesting."

I didn't see a one-to-many field in Django documentation, and was rather saddened by it. Or am I missing something?

# ? Apr 20, 2014 22:42

Blinkz0rz: May 27, 2001; MY CONTEMPT FOR MY OWN EMPLOYEES IS ONLY MATCHED BY MY LOVE FOR TOM BRADY'S SWEATY MAGA BALLS

supermikhail posted:

I didn't see a one-to-many field in Django documentation, and was rather saddened by it. Or am I missing something?

django.db.models.ForeignKey()

# ? Apr 21, 2014 01:19

supermikhail: Nov 17, 2012; "It's video games, Scully."
Video games?"
"He enlists the help of strangers to make his perfect video game. When he gets bored of an idea, he murders them and moves on to the next, learning nothing in the process."
"Hmm... interesting."

I don't get it. It says it's many-to-one, not the other way around, and my google-fu suggest they are not the same... Okay, I've managed to dig up the fact that there is a "Related objects' manager", which ensures that a ForeignKey relationship gets "two-way traffic". I didn't realize that but the fact that the tutorial's "question" had access to "choice_set" was a bit suspicious.

Thanks for making me stare in the right direction for long enough!

# ? Apr 21, 2014 02:01

Ahz: Jun 17, 2001; PUT MY CART BACK? I'M BETTER THAN THAT AND YOU! WHERE IS MY BUTLER?!

You're own structure is a many-to-many structure, a real one, not the hacky thing Django calls its own one.

You're right, you use the related manager to traverse the reverse relationship. I prefer to use the 'related_name' attr to make traversal a little more obvious when coding rather than the default *_set.

# ? Apr 21, 2014 04:43

more like dICK: Feb 15, 2010; This is inevitable.

Is there an easy way to do periodic tasks in Django that doesn't involve Celery and works on Python 3.3+? I'll use Celery if that's what it comes down to, I'm just a bit sick of janitoring init scripts.

# ? Apr 23, 2014 00:41

MonkeyMaker: May 22, 2006; What's your poison, sir?

fletcher posted:

Is it necessary to make a South migration for something like python-social-auth? If you just do a pip install python-social-auth and then ./manage.py schemamigration social.apps.django_app.default --initial, I think the migration file ends up somewhere inside my virtualenv (and thus outside of my version controlled repo). So I'm thinking ./manage.py syncdb is sufficient, no need to use South?

Don't make migrations for software you don't control.

# ? Apr 23, 2014 17:11

Adbot: ADBOT LOVES YOU

# ? May 31, 2024 08:27

fletcher: Jun 27, 2003; ken park is my favorite movie; Cybernetic Crumb

MonkeyMaker posted:

Don't make migrations for software you don't control.

Ok cool, thanks!

# ? Apr 23, 2014 17:36

The Something Awful Forums > Discussion > Serious Hardware/Software Crap > The Cavern of COBOL > Django Web Framework: The 'D' is silent dumbass

«‹›122 »

fletcher posted:

Python code:

code:

Smarmy Coworker posted:

code:

MonkeyMaker posted:

Ahz posted:

Yay posted:

Blinkz0rz posted:

MonkeyMaker posted:

MonkeyMaker posted:

more like dICK posted:

blinkz0rz posted:

code:

code:

code:

Python code:

fletcher posted:

Python code:

supermikhail posted:

more like dICK posted:

fletcher posted:

MonkeyMaker posted: