redis-limpyd-extensions 2

FKStringField

• sadd, to set the reverse relation as the fk of the arguments:

Having:

class Group(RelatedModel):
    parent = FKStringField(self, related_name='children')

The standard:

child_group.parent.set(main_group)
other_child_group.parent.set(main_group)

is the same as the new:

main_group.children.sadd(child_group, other_child_group)

• srem works the same way as sadd but for deleting fk:

The standard:

child_group.parent.delete(main_group)
other_child_group.parent.delete(main_group)

is the same as the new:

main_group.children.srem(child_group, other_child_group)

FKHashableField

• sadd

• srem

Both work the exact same way as for FKStringField, the only difference is that sadd emulates a hset, not a set.

M2MSetField

• sadd

The standard:

group_2.members.sadd(somebody)
group_3.members.sadd(somebody)

is the same as the new:

somebody.membership.sadd(group2, group3)

• srem works the same way as sadd but for removing relations:

The standard:

group_2.members.srem(somebody)
group_3.members.srem(somebody)

is the same as the new:

somebody.membership.srem(group2, group3)

M2MListField

• lpush and rpush, that works for M2MListField like sadd for M2MSetField

If in our Person/Group example members is a M2MListField instead of a M2MSetField,

The standard:

group_2.members.rpush(somebody)
group_3.members.rpush(somebody)

is the same as the new:

somebody.membership.rpush(group2, group3)

• lrem works the same way as rpush and lpush but for removing relations:

The standard:

group_2.members.lrem(0, somebody)  # 0 for "all occurences"
group_3.members.lrem(0, somebody)

is the same as the new:

somebody.membership.lrem(group2, group3)  # the count is forced to 0

M2MSortedSetField

• zadd that works for M2MSortedSetField like sadd for M2MSetField, but managing scores. Arguments can be set the same way as the normal zadd command.

If in our Person/Group example members is a M2MSortedSetField instead of a M2MSetField, using the score to save the date of membership

The standard:

group_2.members.zadd({somebody: sometime})  # sometime, a float, can be a call to time.time()
group_3.members.zadd({somebody: another_time})

is the same as the new:

somebody.membership.zadd({group2: sometime, group3: another_time})

• zrem works the same way as zadd, without the score, but for removing relations:

The standard:

group_2.members.zrem(somebody)
group_3.members.zrem(somebody)

is the same as the new:

somebody.membership.zrem(group2, group3)

Filtering

To filter on indexable dynamic fields, there is two ways too:

• use the classic way, if you now the dynamic part in advance:

MyModel.collection(foo_bar='three')

• use the new dynamic_filter method:

MyModel.collection().dynamic_filter('foo', 'bar', 'three')

Parameters are: the field name, the dynamic part, the value for the filter and, not show in the previous example, the index suffix to use.

This suffix is default to ‘’.

But if what you want to do is

MyModel.collection(foo_bar__eq='three')

You can use dynamic_filter this way:

MyModel.collection().dynamic_filter('foo', 'bar', 'three', 'eq')  # you can use '__eq' too

The collection manager used with ModelWithDynamicFieldMixin depends on ExtendedCollectionManager, so you can chain filters and dynamic filters on the resulting collection.

Dynamic related fields

Dynamic fields also work with related fields, exactly the same way. There is only two additions:

• if you pass a model instance in the get_for method, it will be translated to it’s pk

• the first argument of a “related collection” is the dynamic part (can also be an instance)

An exemple using dynamic related fields:

from limpyd.fields import PKField
from limpyd_extensions.dynamic.model import ModelWithDynamicFieldMixin
from limpyd_extensions.dynamic.related import DynamicM2MSetField

class Tag(MyBaseModel):
    slug = PKField()

class Person(MyBaseModel):
    name = PKField()

class Movie(ModelWithDynamicFieldMixin, MyBaseModel):
    name = PKField()
    tags = DynamicM2MSetField(Tag, related_name='movies')

somebody = Person(name='Somebody')
matrix = Movie(name='Matrix')
cool = Tag(name='cool')

matrix.tags.get_for(somebody).sadd(cool)
# same as: matrix.tags(somebody).sadd(cool)

cool_movies_for_somebody = cool.movies(somebody)  # the related collection
# ['Matrix']

Provided classes

Here is the list of modules and classes provided with the limpyd_extensions.dynamic module:

• model

  • mixins

    • ModelWithDynamicFieldMixin(object) - A mixin tu use for your model with dynamic fields

• collection

  • mixins

    • CollectionManagerForModelWithDynamicFieldMixin(object) - A mixin to use if you want to add the dynamic_filter method to your own collection manager

  • full classes

    • CollectionManagerForModelWithDynamicField(CollectionManagerForModelWithDynamicFieldMixin, ExtendedCollectionManager) - A simple class inheriting from our mixin and the manager from limpyd.contrib.collection

• field

  • mixins

    • DynamicFieldMixin(object) - A mixin within all the stuff for dynamic fields is done, to use to add dynamic field support to your own fields

  • full classes All fields simply inherits from our mixin and the wanted base field, without anymore addition:

    • DynamicStringField(DynamicFieldMixin, StringField)

    • DynamicInstanceHashField(DynamicFieldMixin, InstanceHashField)

    • DynamicListField(DynamicFieldMixin, ListField)

    • DynamicSetField(DynamicFieldMixin, SetField)

    • DynamicSortedSetField(DynamicFieldMixin, SortedSetField)

    • DynamicHashField(DynamicFieldMixin, HashField)

• related

  • mixins

    • DynamicRelatedFieldMixin(DynamicFieldMixin) - A mixin within all the stuff for dynamic related fields is done, to use to add dynamic field support to your own related fields

  • full classes

    • DynamicFKStringField(DynamicRelatedFieldMixin, FKStringField)

    • DynamicFKInstanceHashField(DynamicRelatedFieldMixin, FKInstanceHashField)

    • DynamicM2MSetField(DynamicRelatedFieldMixin, M2MSetField)

    • DynamicM2MListField(DynamicRelatedFieldMixin, M2MListField)

    • DynamicM2MSortedSetField(DynamicRelatedFieldMixin, M2MSortedSetField)