Skip to main content
Join the official 2019 Python Developers SurveyStart the survey!

Filters for Graphene SQLAlchemy integration

Project description

Graphene-SQLAlchemy-Filter

circle-ci coveralls pypi

Filters for Graphene SQLAlchemy integration

preview

Quick start

Create a filter and add it to the graphene field.

from graphene_sqlalchemy_filter import FilterableConnectionField, FilterSet


class UserFilter(FilterSet):
    is_admin = graphene.Boolean()

    class Meta:
        model = User
        fields = {
            'username': ['eq', 'ne', 'in', 'ilike'],
            'is_active': [...],  # shortcut!
        }

    @staticmethod
    def is_admin_filter(info, query, value):
        if value:
            return User.username == 'admin'
        else:
            return User.username != 'admin'


class Query(ObjectType):
    all_users = FilterableConnectionField(UserConnection, filters=UserFilter())

Now, we’re going to create query.

{
  allUsers (
    filters: {
      isActive: true,
      or: [
        {isAdmin: true},
        {usernameIn: ["moderator", "cool guy"]}
      ]
    }
  ){
    edges {
      node {
        id
        username
      }
    }
  }
}

🔥 Let’s rock! 🔥


Filters

FilterSet class must inherit graphene_sqlalchemy_filter.FilterSet or your subclass of this class.

There are three types of filters:

  1. automatically generated filters
  2. simple filters
  3. filters that require join

Automatically generated filters

class UserFilter(FilterSet):
   class Meta:
       model = User
       fields = {
           'username': ['eq', 'ne', 'in', 'ilike'],
           'is_active': [...],  # shortcut!
       }

Metaclass must contain the sqlalchemy model and fields.

Automatically generated filters must be specified by fields variable. Key - field name of sqlalchemy model, value - list of expressions (or shortcut).

Shortcut (default: [...]) will add all the allowed filters for this type of sqlalchemy field.

Key Description GraphQL postfix
eq equal  
ne not equal Ne
like like Like
ilike insensitive like Ilike
is_null is null IsNull
in in In
not_in not in NotIn
lt less than Lt
lte less than or equal Lte
gt greater than Gt
gte greater than or equal Gte
range in range Range
contains contains (PostgreSQL array) Contains
contained_by contained_by (PostgreSQL array) ContainedBy
overlap overlap (PostgreSQL array) Overlap

Simple filters

class UserFilter(FilterSet):
    is_admin = graphene.Boolean()

    @staticmethod
    def is_admin_filter(info, query, value):
        if value:
            return User.username == 'admin'
        else:
            return User.username != 'admin'

Each simple filter has a class variable that passes to GraphQL schema as an input type and function <field_name>_filter that makes filtration.

The filtration function takes the following arguments: * info - ResolveInfo graphene object * query - sqlalchemy query (not used in that filters type) * value - the value of a filter

The return value can be any type of sqlalchemy clause. This means that you can return not_(and_(or_(...), ...)).

Metaclass is not required if you do not need automatically generated filters.

Filters that require join

This type of filter is the same as simple filters but has a different return type.

The filtration function should return a new sqlalchemy query and clause (like simple filters).

class UserFilter(FilterSet):
    is_moderator = graphene.Boolean()

    @classmethod
    def is_admin_filter(cls, info, query, value):
        membership = cls.aliased(query, Membership, name='is_moderator')

        query = query.join(
            membership,
            and_(
                User.id == membership.user_id,
                membership.is_moderator.is_(True),
            ),
        )

        if value:
            filter_ = membership.id.isnot(None)
        else:
            filter_ = membership.id.is_(None)

        return query, filter_

Model aliases

The function cls.aliased(query, model, name='...') returns sqlalchemy alias from the query. It has one differing parameter - query (SQLAlchemy Query object). Other arguments are the same as sqlalchemy.orm.aliased.

Identical joins will be skipped by sqlalchemy.

Changed in version 1.7: The first parameter is now a query.

Features

Rename GraphQL filter field

class CustomField(FilterableConnectionField):
    filter_arg = 'where'


class Query(ObjectType):
    all_users = CustomField(UserConnection, where=UserFilter())
    all_groups = FilterableConnectionField(GroupConnection, filters=GroupFilter())
{
  allUsers (where: {isActive: true}){
    edges { node { id } }
  }
  allGroups (filters: {nameIn: ["python", "development"]}){
    edges { node { id } }
  }
}

Rename expression

class BaseFilter(FilterSet):
    GRAPHQL_EXPRESSION_NAMES = dict(
        FilterSet.GRAPHQL_EXPRESSION_NAMES,
        **{'eq': 'equal', 'not': 'i_never_asked_for_this'}
    )

    class Meta:
        abstract = True


class UserFilter(BaseFilter):
    class Meta:
        model = User
        fields = {'first_name': ['eq'], 'last_name': ['eq']}
{
  allUsers (filters: {iNeverAskedForThis: {firstNameEqual: "Adam", lastNameEqual: "Jensen"}}){
    edges { node { id } }
  }
}

Custom shortcut value

class BaseFilter(FilterSet):
    ALL = '__all__'

    class Meta:
        abstract = True


class UserFilter(BaseFilter):
    class Meta:
        model = User
        fields = {'username': '__all__'}

Localization of documentation

class BaseFilter(FilterSet):
    DESCRIPTIONS = {
        'eq': 'Полностью совпадает.',
        'ne': 'Не совпадает.',
        'like': 'Регистрозависимая проверка строки по шлабону.',
        'ilike': 'Регистронезависимая проверка строки по шлабону.',
        'regexp': 'Регистрозависимая проверка строки по регулярному выражению.',
        'is_null': 'Равно ли значение `null`. Принемает `true` или `false`.',
        'in': 'Проверка вхождения в список.',
        'not_in': 'Проверка не вхождения в список.',
        'lt': 'Меньше, чем указанное значение.',
        'lte': 'Меньше или равно указанному значению.',
        'gt': 'Больше, чем указанное значение.',
        'gte': 'Больше или равно указанному значению.',
        'range': 'Значение входит в диапазон значений.',
        'and': 'Объединение фильтров с помощью ``AND``.',
        'or': 'Объединение фильтров с помощью ``OR``.',
        'not': 'Отрицание указанных фильтров.',
    }

    class Meta:
        abstract = True

Custom expression

def today_filter(field, value: bool):
    today = func.date(field) == date.today()
    return today if value else not_(today)


class BaseFilter(FilterSet):
    # Add expression.
    TODAY = 'today'

    EXTRA_EXPRESSIONS = {
        'today': {
            # Add the name of the expression in GraphQL.
            'graphql_name': 'today',
            # Update allowed filters (used by shortcut).
            'for_types': [types.Date, types.DateTime],
            # Add a filtering function (takes the sqlalchemy field and value).
            'filter': today_filter,
            # Add the GraphQL input type. Column type by default.
            'input_type': (
                lambda type_, nullable, doc: graphene.Boolean(nullable=False)
            ),
            # Description for the GraphQL schema.
            'description': 'It is today.',
        }
    }

    class Meta:
        abstract = True


class PostFilter(BaseFilter):
    class Meta:
        model = Post
        fields = {'created': ['today'], 'updated': [...]}
{
  allPosts (filters: {createdToday: false, updatedToday: true}){
    edges { node { id } }
  }
}

Custom column types

ALLOWED_FILTERS and EXTRA_ALLOWED_FILTERS only affect shortcut.

If you do not use the shortcut, you can skip the next steps described in the section.

class MyString(types.String):
    pass


class BaseFilter(FilterSet):
    # You can override all allowed filters
    # ALLOWED_FILTERS = {types.Integer: ['eq']}

    # Or add new column type
    EXTRA_ALLOWED_FILTERS = {MyString: ['eq']}

    class Meta:
        abstract = True

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 graphene-sqlalchemy-filter, version 1.9.1
Filename, size File type Python version Upload date Hashes
Filename, size graphene_sqlalchemy_filter-1.9.1-py3-none-any.whl (12.3 kB) File type Wheel Python version py3 Upload date Hashes View hashes
Filename, size graphene-sqlalchemy-filter-1.9.1.tar.gz (14.8 kB) File type Source Python version None Upload date Hashes View hashes

Supported by

Elastic Elastic Search Pingdom Pingdom Monitoring Google Google BigQuery Sentry Sentry Error logging AWS AWS Cloud computing DataDog DataDog Monitoring Fastly Fastly CDN SignalFx SignalFx Supporter DigiCert DigiCert EV certificate StatusPage StatusPage Status page