Skip to main content

A django app to apply filters on drf querysets using query params with validations using voluptuous.

Project description

# drf-url-filters

**drf-url-filters** is a simple django app to apply filters on drf
modelviewset's queryset in a clean, simple and configurable way. It also
supports validations on incoming query params and their values. A beautiful
python package [voluptouos](https://github.com/alecthomas/voluptuous) is being
used for validations on the incoming query parameters. The best part about
voluptouos is you can define your own validations as per your query params
requirements.

# Quick start
---
**Installation**

1. Download `drf-url-filters` app package from this git repo or can be
installed using python-pip like `pip install drf-url-filters`.

2. Add `filters` in INSTALLED_APPS of settings.py file of django project.

**How it works?**

1. Your View or ModelViewSet should inherit `FiltersMixin` from
`filters.mixins.FiltersMixin`.

2. To apply filters using `drf-url-filters` we need to configure our view to
have a dict mapping `filter_mappings` which converts incoming query parameters
to query you want to make on the column name on the queryset.

# validations.py

```python

from filters.schema import base_query_param_schema
from filters.validations import (
CSVofIntegers,
IntegerLike,
DatetimeWithTZ
)

# make a validation schema for players filter query params
players_query_schema = base_query_param_schema.extend(
{
"id": IntegerLike(),
"name": unicode,
"team_id": CSVofIntegers(), # /?team_id=1,2,3
"install_ts": DatetimeWithTZ(),
"update_ts": DatetimeWithTZ(),
}
)
```

# views.py

```python

from rest_framework import (
viewsets,
filters,
)

from .models import Player, Team
from .pagination import ResultSetPagination
from .serializers import PlayerSerializer, TeamSerializer
from .validations import teams_query_schema, players_query_schema
from filters.mixins import (
FiltersMixin,
)


class PlayersViewSet(FiltersMixin, viewsets.ModelViewSet):
"""
This viewset automatically provides `list`, `create`, `retrieve`,
`update` and `destroy` actions.
"""
serializer_class = PlayerSerializer
pagination_class = ResultSetPagination
filter_backends = (filters.OrderingFilter,)
ordering_fields = ('id', 'name', 'update_ts')
ordering = ('id',)

# add a mapping of query_params to db_columns(queries)
filter_mappings = {
'id': 'id',
'name': 'name__icontains',
'team_id': 'teams',
'install_ts': 'install_ts',
'update_ts': 'update_ts',
'update_ts__gte': 'update_ts__gte',
'update_ts__lte': 'update_ts__lte',
}

# add validation on filters
filter_validation_schema = players_query_schema

def get_queryset(self):
"""
Optionally restricts the queryset by filtering against
query parameters in the URL.
"""
query_params = self.request.query_params
url_params = self.kwargs

# get queryset_filters from FilterMixin
queryset_filters = self.get_db_filters(url_params, query_params)

# This dict will hold filter kwargs to pass in to Django ORM calls.
db_filters = queryset_filters['db_filters']

# This dict will hold exclude kwargs to pass in to Django ORM calls.
db_excludes = queryset_filters['db_excludes']

# fetch queryset from Players model
queryset = Player.objects.prefetch_related(
'teams' # use prefetch_related to minimize db hits.
).all()

return queryset.filter(**db_filters).exclude(**db_excludes)
```

With the use of `drf-url-filters` adding a new filter on a new column is as
simple as adding a new key in the dict. Prohibitting a filter on particular
column is same as removing a key value mapping from the `filter_mappings` dict.


# LICENSE
[MIT License](LICENSE.MD)
Copyright (c) 2016 Manjit Kumar.

# Credits
Special thanks to authors of
[voluptouos](https://github.com/alecthomas/voluptuous) and friends
[cdax](https://github.com/cdax) and [saurabhjha](https://github.com/SaurabhJha)
who encourage people to contribute into open source community.

# Support
Please [open an issue]
(https://github.com/manjitkumar/drf-url-filters/issues/new) for support.

Project details


Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Files for drf-url-filters, version 0.2.1
Filename, size File type Python version Upload date Hashes
Filename, size drf-url-filters-0.2.1.tar.gz (6.5 kB) File type Source Python version None Upload date Hashes View

Supported by

AWS AWS Cloud computing Datadog Datadog Monitoring DigiCert DigiCert EV certificate Facebook / Instagram Facebook / Instagram PSF Sponsor Fastly Fastly CDN Google Google Object Storage and Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Salesforce Salesforce PSF Sponsor Sentry Sentry Error logging StatusPage StatusPage Status page