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Friendly ID(Python 3.X)

This is just modified version of [friendly id](https://djangosnippets.org/snippets/1249/) for make this script compatible with python 3.x Invoice numbers like "0000004" are a little unprofessional in that they expose how many sales a system has made, and can be used to monitor the rate of sales over a given time. They are also harder for customers to read back to you, especially if they are 10 digits long. This is simply a perfect hash function to convert an integer (from eg an ID AutoField) to a unique number. The ID is then made shorter and more user-friendly by converting to a string of letters and numbers that wont be confused for one another (in speech or text). To use it: import friendly_id class MyModel(models.Model): invoice_id = models.CharField(max_length=6, null=True, blank=True, unique=True) def save(self, *args, **kwargs): super(MyModel, self).save(*args, **kwargs) # Populate the invoice_id if it is missing if self.id and not self.invoice_id: self.invoice_id = friendly_id.encode(self.id) self.save() if self.id and not self.invoice_id When an object from this model is saved, an invoice ID will be generated that does not resemble those surrounding it. For example, where you are expecting millions of invoices the IDs generated from the AutoField primary key will be: obj.id obj.invoice_id 1 TTH9R 2 45FLU 3 6ACXD 4 8G98W 5 AQ6HF 6 DV3TY ... 9999999 J8UE5 The functions are deterministic, so running it again sometime will give the same result, and generated strings are unique for the given range (the default max is 10,000,000). Specifying a higher range allows you to have more IDs, but all the strings will then be longer. You have to decide which you need: short strings or many strings :-) This problem could have also been solved using a random invoice_id generator, but that might cause collisions which cost time to rectify, especially when a decent proportion of the available values are taken (eg 10%). Anyhow, someone else has now already written this little module for you, so now you don't have to write your own :-)

  • database
  • field-id
  • invoice-id
  • invoice
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Decorator to add placeholders to field

Decorator to automagically add placeholders to form widgets. `cls` can be any class derived from `django.forms.Form` or `django.forms.ModelForm`. The field labels are used as value for the placeholder. This will affect all form instances of this class. * add_placeholders only to forms.TextInput and form.Textarea * add_placeholders_to_any_field adds placeholders to any field Usage: @add_placeholders class Form(forms.Form): name = forms.CharField The name field will render as `<input type="text" placeholder="name">`

  • decorator
  • placeholder
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django smartround filter

rounds floats in more human readable format e.g. 341.123434 mUSD -> 341mUSD 0.45345345 mUSD -> 0.5 mUSD 0.034545 mUSD -> 0.03 mUSD 0.0014545 mUSD -> 0.001 mUSD etc.

  • smart round
  • smartfloatformat
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Custom DRF browsable API interface for InBBoxFilter of django-rest-framework-gis

[DRF browsable API interface](http://www.django-rest-framework.org/api-guide/filtering/#customizing-the-interface) for django-rest-framework-gis [InBBoxFilter](https://github.com/djangonauts/django-rest-framework-gis#inbboxfilter) Tested with Django==1.10.5 django-filter==1.0.1 djangorestframework==3.5.4 djangorestframework-gis==0.11 ![Screenshot](http://joxi.ru/8AnzxLDTOEgeAO.png)

  • django
  • django-rest-framework
  • django-rest-framework-gis
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query builder

""" Takes arguments & constructs Qs for filter() We make sure we don't construct empty filters that would return too many results We return an empty dict if we have no filters so we can still return an empty response from the view """

  • query
  • queryset
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aggregate filter

Makes it possible to add a filtering condition directly after the aggregate function (or possible, `aggregate(expression) WITHIN GROUP (ordering clause)`. This is mostly useful if the annotation has two or more expressions, so it's possible to compare the result with and without the applied filter; it's more compact than using `Case`. It's suggested to add `values` to the queryset to get a proper group by. Usage example: `books = Book.objects.values('publisher__name').annotate( count=Count('*'), filtercount=Filter(expression=Count('publisher__name'), condition=Q(rating__gte=5)) ) ` Supported on Postgresql 9.4+. Possible other third-party backends.

  • filter
  • postgresql
  • olap
  • aggregate
  • expression
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replace

Small example of how to write your own function. This is not available in Django. The function just replaces static text strings, regular expressions are not supported. The syntax is the same in SQLite, PostgreSQL, MySQL and Oracle.

  • text
  • replace
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CNPJ and CPF Validation for Models

The code was placed inside a helper file without using a class. The Django validator was not designed to work with validator classes, it would appear, so retrieving the value from the field proved to be a hassle. Just create a helper file, import it on your model, and use the validator in the standard way, as such: cnpj = models.CharField(unique=True, max_length=14, validators=[validate_CNPJ]) cpf = models.CharField(unique=True, max_length=14, validators=[validate_CPF])

  • model
  • validation
  • cnpj
  • cpf
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Simply Gravatar Templatetags

Simply Gravatar Templatetags, for example the name of this templatetag is: `templatetags/gravatar_tags.py`, this supported for Python2 or Python3.

  • django
  • image
  • templatetag
  • gravatar
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Django chunked queryset iterator

The function slices a queryset into smaller querysets containing chunk_size objects and then yield them. It is used to avoid memory error when processing huge queryset, and also database error due to that the database pulls whole table at once. Concurrent database modification wouldn't make some entries repeated or skipped in this process.

  • django
  • python
  • database
  • queryset
  • iterator
  • memoryerror
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