django-sequere 0.2.0.dev

Compatibility

This library is compatible with:

• python2.6, django1.4

• python2.6, django1.5

• python2.6, django1.6

• python2.7, django1.4

• python2.7, django1.5

• python2.7, django1.6

• python3.3, django1.5

• python3.3, django1.6

If I’m a liar, you can ping me.

Installation

1. Either check out the package from GitHub or it pull from a release via PyPI

   pip install django-sequere

2. Add sequere to your INSTALLED_APPS

   INSTALLED_APPS = (
       'sequere',
   )

Usage

In Sequere any resources can follow any resources and vice versa.

Let’s say you have two models:

# models.py

from django.db import models

class User(models.Model):
    username = models.Charfield(max_length=150)


class Project(models.Model):
    name = models.Charfield(max_length=150)

Now you to register them in sequere to identify them when a resource is following another one.

# sequere_registry.py

from .models import Project, User

import sequere

sequere.register(User)
sequere.register(Project)

Sequere uses the same concepts as Django Admin, so if you have already used it, you will not be lost.

Last step is to tell Sequere to autodiscover your registered models:

# urls.py

from django.conf.urls.defaults import patterns

import sequere; sequere.autodiscover()


urlpatterns = patterns(
    '',
    # Your urls here
)

You can now use Sequere like any other application, let’s play with it:

In [1]: from sequere.models import (follow, unfollow, get_followings_count, is_following,
                                    get_followers_count, get_followers, get_followings)

In [2]: from myapp.models import User, Project

In [3]: user = User.objects.create(username='thoas')

In [4]: project = Project.objects.create(name'La classe americaine')

In [5]: follow(user, project)  # thoas will now follow "La classe americaine"

In [6]: is_following(user, project)
True

In [7]: get_followers_count(project)
1

In [8]: get_followings_count(user)
1

In [9]: get_followers(user)
[]

In [10]: get_followers(project)
[(<User: thoas>, datetime.datetime(2013, 10, 25, 4, 41, 31, 612067))]

In [11]: get_followings(user)
[(<Project: La classe americaine, datetime.datetime(2013, 10, 25, 4, 41, 31, 612067))]

If you are as lazy as me to provide the original instance in each sequere calls, use SequereMixin:

# models.py

from django.db import models

from sequere.mixin import SequereMixin

class User(SequereMixin, models.Model):
    username = models.Charfield(max_length=150)

class Project(SequereMixin, models.Model):
    name = models.Charfield(max_length=150)

Now you can use calls directly from the instance:

In [1]: from myapp.models import User, Project

In [2]: user = User.objects.create(username='thoas')

In [3]: project = Project.objects.create(name'La classe americaine')

In [4]: user.follow(project)  # thoas will now follow "La classe americaine"

In [5]: user.is_following(project)
True

In [6]: project.get_followers_count()
1

In [7]: user.get_followings_count()
1

In [8]: user.get_followers()
[]

In [9]: project.get_followers()
[(<User: thoas>, datetime.datetime(2013, 10, 25, 4, 41, 31, 612067))]

In [10]: user.get_followings()
[(<Project: La classe americaine, datetime.datetime(2013, 10, 25, 4, 41, 31, 612067))]

So much fun!

Backends

INSTALLED_APPS = (
    'sequere',
    'sequere.backends.database',
)

# sequere_registry.py

from myapp.models import Project

from sequere.base import ModelBase

import sequere


class ProjectSequere(ModelBase):
    identifier = 'projet' # the french way ;)

sequere.registry(Project, ProjectSequere)

INCR sequere:global:uid    =>  1
SET sequere:uid:{identifier}:{id} 1
HMSET sequere:uid::{id} identifier {identifier} object_id {id}

INCR sequere:uid:{to_uid}:followers:count => 1
INCR sequere:uid:{to_uid}:followers:{from_identifier}:count => 1

INCR sequere:uid:{from_uid}:followings:count => 1
INCR sequere:uid:{from_uid}:followings:{to_identifier}:count => 1

ZADD sequere:uid:{to_uid}:followers {from_uid} {timestamp}
ZADD sequere:uid:{to_uid}:followers:{from_identifier} {from_uid} {timestamp}

ZADD sequere:uid:{from_uid}:followings {to_uid} {timestamp}
ZADD sequere:uid:{from_uid}:followings{to_identifier} {to_uid} {timestamp}

ZRANGEBYSCORE sequere:uid:{uid}:followers -inf +inf

ZRANGEBYSCORE sequere:uid:{uid}:followings =inf +inf

ZREVRANGEBYSCORE sequere:uid:{uid}:followers +inf -inf

Configuration

SEQUERE_REDIS_CONNECTION = {
    'host': 'localhost',
    'port': 6379,
    'db': 0,
}

SEQUERE_REDIS_CONNECTION = 'redis://username:password@localhost:6379/0'

SEQUERE_REDIS_CONNECTION_CLASS = 'myproject.myapp.mockup.Connection'

SEQUERE_REDIS_PREFIX = 'sequere:myproject:'

Resources

• haplocheirus: a Redis backed storage engine for timelines written in Scala

• Case study from Redis documentation: write a twitter clone

• Amico: relationships backed by Redis

• django-constance: a multi-backends settings management application