IT Blog

Dear readers!

I'm glad to show you my new Levels project -

Levels is social network for athletes and people, who conduct active and healthy a way of life. Goals of project are create the platform, where people would can read interesting articles about health and motivation, find various dishes, draw up a plan of training and nutrition, and also talking to other people, that conduct correct a way of life too. In general, I want to inspire people to improve their life energy, thanks to the development of body and spirit, right nutrition, building of positive thoughts and so...

I get strange bug with attachment in django-post-office (at least, it's encountered in version 2.0.8 and lower): when the mail is sent, which consist of html-content with attachment (of any format), the mail is come, but without attachment.

I used next package version:

django==1.10.7 (and lower)
django-post-office==2.0.8 (and lower)

In more detail, the behavior of django-post-office of the specified version and the working of the mail.send() method can be described as follows:

1. When the mail is sent with simple content, using message parameter, and with attachment - it works correctly, i. e. I get mail with attachment.
2. When the mail...

Error Cannot read property 'replace' of undefined in bundle.toolbar.min.js may appear, if CMS page has two placeholders.

In my case this error doesn't allow to open plugin editor window in some placeholders.

You can see error cannot alter table because it has pending trigger events when property of your fields in database is cannot change in one transaction. To understand easy you can see examples.

Romeve blank=True in fields

So, there is model:

# -*- coding: utf-8 -*-
from __future__ import unicode_literals

from django.db import models
from django.utils.encoding import python_2_unicode_compatible


@python_2_unicode_compatible
class MyModel(models.Model):
    title = models.CharField(max_length=100, null=True, blank=True)
    content = models.TextField(null=True, blank=True)
    template = models.CharField(max_length=255, null=True, blank=True)


    def __str__(self):
        return self.title

So null=True is extra useless property for CharField, TextField then you need remove null=True:

...
class MyModel(models.Model):
    title = models.CharField(max_length=100, blank=True)...

Warning: might be referenced before assignment

Use # noinspection PyUnboundLocalVariable, for example:

def get_rate(self, rates, amount):
    for rate_item in rates:
        if amount <= rate_item.amount:
            return rate_item.rate

    # noinspection PyUnboundLocalVariable
    return rate_item.rate

Warning: unexpected argument

Use # noinspection PyArgumentList, for example:

# noinspection PyArgumentList
product = Cloth(product_name='title',product_code='xxx', unit_price=120)

Available identifiers for hiding of warning in PyCharm

In common case, write down # noinspection [warning identifier] before warning row.

# noinspection PyAbstractClass
# noinspection PyArgumentEqualDefault
# noinspection PyArgumentList  # unexpected argument
# noinspection PyAssignmentToLoopOrWithParameter
# noinspection PyAttributeOutsideInit
# noinspection PyAugmentAssignment
# noinspection PyBroadException
# noinspection PyByteLiteral
# noinspection PyCallByClass
#...

Periodically, I get next error:

NoReverseMatch: Reverse for 'my_url_name' with arguments '(u'...',)' and keyword arguments '{}' not found. 0 pattern(s) tried: []

I do not understand quickly why my code is not works. Well, I write down this notes. Check list:

1. Include urls.py of app to project urls.py

urlpatterns = patterns('',
    ...
    url(r'^my_app/', include('my_app.urls')),
    ...
)

2. Include url to urls.py of app:

urlpatterns = patterns('',
    url(r'^my-url-name/(?P<my_object_id>\d+)/$', my_app.views.my_view, name='my_url_name'),
)

3. Add required arguments to urls.py

urlpatterns = patterns('',
    url(r'^my-url-name/(?P<my_object_id>\d+)/$', my_app.views.my_view, name='my_url_name'),
)

4. Add required arguments with call 'url' function in template or 'reverse' function in...

If you get this error:

django.db.migrations.state.InvalidBasesError: Cannot resolve bases for [<ModelState: 'cms.PageUser'>]

Then the problem is in 0001_initial.py migration of django cms. This migration try to refer to migrations of User model:

class Migration(migrations.Migration):

    dependencies = [
        ('auth', '__first__'),
        migrations.swappable_dependency(settings.AUTH_USER_MODEL),  # refer to migrations of User model
        ('sites', '__first__'),
    ]
    ...

And doesn't find, because there aren't migrations yet for our model of custom user. So before the creations of migrations you need comment djangocms_text_ckeditor and cms applications in settings.py:

INSTALLED_APPS = (
    ...
    'django.contrib.auth',
    'my_custom_auth',  # our custom User model
    ...

    # 'djangocms_text_ckeditor',
    # 'cms',
    ...
)

Run makemigrations:...

For finding of changed pages (or dirty pages) you can use Title model:

dirty_titles = Title.objects.filter(publisher_is_draft=True, publisher_state=PUBLISHER_STATE_DIRTY)

Result can displayed as like:

{% if dirty_titles %}
    <p style="font-weight: bold;">Dirty pages:</p>
    {% for title in dirty_titles %}
        <p class="changelink"><a target="_blank" href="{{ title.page.get_absolute_url }}">{{ title.page.get_title }}</a></p>
    {% endfor %}
{% endif %}

If you have multilanguage site, then you need provide group by languages (this property is in instance of Title class). Or you can display your result as like page structure in django cms.

I use my solution for display in information block "Notification" to notify about unpublished changes on pages.

To solve the problem ValueError: jpeg is required unless explicitly disabled using --disable-jpeg, aborting install package:

apt-get install libjpeg-dev

There is a round(number, ndigits) function for rounding of numbers, where number is required number for rounding, ndigits is a number of simbols after comma. For example:

round(2.137, 2)  # = 2.14

Round function has some feature that consists in the fact that it works on the principle of bank rounding to round off the numbers in which the last five is a sign, for example:

round(2.05, 1)  # = 2.0
round(2.15, 1)  # = 2.1
round(2.25, 1)  # = 2.3
round(2.35, 1)  # = 2.4
round(2.45, 1)  # = 2.5
round(2.55, 1)  # = 2.5
round(2.65, 1)  # =...