better paginator template tag

This is slight improvement over [Paginator|Snippet 73](http://www.djangosnippets.org/snippets/73/). That used to not work properly if querystring already contains other parameters, like search result page. website/paginator.html: <br /><center> <span class="lbottom"> {% if has_previous %}<a href="{{ path }}page={{ previous }}"><< Previous </a>{% else %}<span>Previous </span>{% endif %} {% if show_first %}<a href="{{ path }}page=1">First </a>{% endif %} {% for page_no in page_numbers %} {% ifnotequal page_no page %} <a href="{{ path }}page={{ page_no }}">{{ page_no }} </a> {% else %} {{ page_no }} {% endifnotequal %} {% endfor %} {% if show_last %}<a href="{{ path }}page={{ pages }}">Last </a>{% endif %} {% if has_next %}<a href="{{ path }}page={{ next }}">Next >></a>{% else %}<span>Next </span>{% endif %} </span> <br /></center>

• templatetag
• paginator

Sun 11 Jul 2010 Read More

Django model cron jobs

Inspired by [snippet 1126](http://www.djangosnippets.org/snippets/1126/), I thought I would post a module that stores crontab entries in a database, with a less powerful, but more end-user friendly API. ("twice a week starting on Sat 1 Dec 2007, 6:23am", instead of "23 6,18 * * *"). The crontab is synchronised when an entry is changed, and relevant environment variables, function name and arguments are provided. You might want to store this as an app called "scheduler" to match the imports. Enjoy!

• cron-jobs
• scheduled-events

Sun 07 Aug 2011 Read More

Prefill ForeignKey caches

Provides an efficient means of looking up multiple related model instances for a range of objects by pre-filling the cache attribute used by `SingleRelatedObjectDescriptor` with either complete model instances or a dict containing only specified fields, looking up all required data with a single query. Example usage: C:\django_projects\soclone>django-admin.py shell >>> from soclone.models import Question >>> from soclone.views import populate_fk_caches >>> from django.db import connection >>> from django.contrib.auth.models import User >>> q = Question.objects.get(id=1) >>> a = list(q.answers.all()) >>> connection.queries = [] >>> populate_fk_caches(User, ( ... ((q,), ('author', 'last_edited_by', 'closed_by')), ... (a, ('author', 'last_edited_by')), ... ), ... fields=('username', 'gravatar', 'reputation', 'gold', 'silver', ... 'bronze')) >>> connection.queries [{'time': '0.000', 'sql': u'SELECT "auth_user"."id", "auth_user"."username", "au th_user"."gravatar", "auth_user"."reputation", "auth_user"."gold", "auth_user"." silver", "auth_user"."bronze" FROM "auth_user" WHERE "auth_user"."id" IN (1, 2)' }]

• foreignkey
• cache
• prefill

Sun 11 Jul 2010 Read More

Twisted protocol for receiving logging module messages over a socket

When using Python's logging module in a concurrent environment (e.g. mod_python), messages get dropped by the standard file-based handlers. The [SocketHandler](http://www.python.org/doc/2.5.2/lib/node414.html) allows you to send logging messages to a remote socket. This snippet provides code for listening for such messages and writing them out to a log file. The final log file is configured as a standard logging file-based handler.

• logging
• twisted

Sun 11 Jul 2010 Read More

update_or_create

Django provides a `get_or_create` helper method in the `models.Manager` class which looks up an object for the given `kwargs`, creating one if necessary. But sometime you need a method which updates the object with given `kwargs` or creates it if it's not found. This snippet provides the helper for that purpose. Use the snippet like this: from django.db import models class PersonManager(models.Manager): update_or_create = _update_or_create class Person(models.Model): first_name = models.CharField() last_name = models.CharField() city = models.CharField() objects = PersonManager() person, created, updated = Person.objects.update_or_create(first_name="John", last_name="Smith", defaults=dict(city="London")) The method returns a tuple of (`object`, `created`, `updated`), where `created` and `updated` are booleans specifying whether an `object` was created or updated respectively. Both `created` and `updated` are `false` if `object` is neither created nor updated (that is `object` has just been fetched "as is" from db). This happens if the update fails.

• model
• helper
• update
• create

Tue 13 Dec 2011 Read More

Jinja2 integration + application specific functions/filters/tests

Jinja2 is an alternative template system that can be plugged into django. It offers greator flexibility in presentation logic; if you find the django template system too restrictive, you should have a look at Jinja2 (The syntax is very similar). In Jinja, you don't need costum tags (most of the time), because you can call functions and pass them parameters too! The only problem is that you cannot "load" functions from the template, this "loading" must be done by the code that renders the template. Same goes for filters and tests. If you need only two or three functions/filters, no problem, you can manually add them to the Environment object; but this method doesn't really scale with real-life webapps. This module/snippet offers a solution by allowing the user to define application-specific functions and filters and load them into the jinja2 environment automatically. Here's how to use this: 1. Install Jinja2 (for a quick & dirty installation, you can just put the jinja2 folder in a folder that's in PYTHONPATH) 2. Save this python module somewhere and call it something meaningful (I have it as jinja.py in my project directory) 3. Whenever you need to respond (an HttpResponse) with a template that's rendered by jinja, import this module and call `return jrespond( template_name, context )` 4. Any filters or functions you define in any of your applications will be readily available inside the template (see the documentation in code)

• template
• templates
• jinja
• template-tags
• jinja2

Sun 11 Jul 2010 Read More

Chain multiple querysets into one

This class acts as a wrapper around multiple querysets. Use it if you want to chain multiple QSs together without combining them with | or &. eg., to put title matches ahead of body matches: >>> qs1 = Event.objects.filter(## title matches ##) >>> qs2 = Event.objects.filter(## matches in other fields ##) >>> qs = MultiQuerySet(qs1, qs2) >>> len(qs) >>> paginator = Paginator(qs) >>> first_ten = qs[:10] It effectively acts as an immutable, sliceable QuerySet (with only a very limited subset of the QuerySet api)

• queryset
• chain
• multi

Sun 11 Jul 2010 Read More

change SITE_ID on fly

Django SITE_ID is a global setting, so the site framework requires you to run multiple instances of Django; at least one for each site. But i want have one instance for multiple sites. This snippet solve this task by change SITE_ID on fly. /sorry my bad english/

• settings
• site_id
• site-contrib

Sun 11 Jul 2010 Read More

Django JQuery Autocomplete for Model Selection

This is a general JQuery Autocomplete Form Field for selecting any model instance in your forms. 1 Download jquery.1.2.6 and the jquery autocomplete plugin http://bassistance.de/jquery-plugins/jquery-plugin-autocomplete/, place theme somewhere in your media directory (in this case {{ MEDIA__URL}}/js/ 2 copy fields.py to anywhere in your python-path (in this case utils.fields) 3 create a view for the ajax request that receives a query and returns a key|value list, and register it in your urls.py 4 Just Use the fields in any form like in forms.py

• selection
• model
• jquery
• autocomplete

Thu 15 Aug 2013 Read More

simple email validation function

This very basic function I was missing in this part of the Django Documentation when creating a custom MultiEmailField: http://docs.djangoproject.com/en/dev/ref/forms/validation/

• email
• validation

Tue 04 Sep 2012 Read More

Photologue wiki-syntax templatetag

**updated 12/16/08** I run several blogs by visual-artists and web-designers who want a quick way to insert images into their blog without the awkwardness of WSYIWYG and without the technicality of code (eww...). Thanks in advance for your input. #Syntax in a blog goes: [[thumb:the-image-slug]] # Gives you a thumbnail [[image:the-image-slug]] # Presents full-size-image Then of course: {% blog.post|yeagowiki %} You will also need to create some templates (see snippet). Here's a sample: <!-- /templates/photologue/image_snippet.html --> <div class="photologue-image"> <a href="{% if url %}{{ url }}{% else %}/media/{{ image.image }}{% endif %}"> <img src="{{ image.get_display_url }}" /> </a> <p class="photologue-image-caption">{{ image.caption }}</p> </div>

• templatetag
• markdown
• wiki
• photologue

Sun 11 Jul 2010 Read More

Session Wizard

This a wizard tool similar to the one in django.contrib.formtools, but it uses a session. I hope to eventually get this into shape and contribute it to the formtools package, but for right now, here it is. The wizard steps are broken into 2 categories: Show Form and Submit Form Each category has it's own hooks for manipulating the process, for instance you can short-circuit a process_submit_form() and go straight to done() via a return from preprocess_submit_form(). Sorry for the lack of documentation on this. Here's an example urls.py entry : `(r'^estimate/(?P<page0>\d+)/$', EstimateWizard([EstimateCustomer, EstimateJob, EstimateRoom]))` where EstimateCustomer, Job, and Room are Form classes and EstimateWizard extends SessionFormWizard

• session
• form
• wizard

Sun 11 Jul 2010 Read More

FormHandler - take the legwork out of form processing

Take the legwork out of processing forms. Most people have a very specific structure to how they process forms in views. If the request method is "GET", then some HTML (with the blank form) is rendered. If the method is "POST", then the form is validated. If the form is invalid, some other HTML is displayed. If valid, the data is submitted and processed in some way. In order to do this all in a much nicer way, simply subclass `FormHandler`, define three methods (`valid`, `invalid` and `unbound`), point to the form, and use the subclass as your view in the URLconf.

• views
• forms
• view
• form
• view-as-a-class
• formhandler
• form-handler

Sat 05 Nov 2011 Read More

Link Media Command

A command for manage.py which scans through installed applications the way admin.autodiscover does, just looking for media folders. It then creates a symbolic link to the media under MEDIA_ROOT/app_name. Usage: save in an apps management/commands folder and run with "python manage.py linkmedia" Only works on *nix systems, but there should be an equivilent way to do this with windows using .lnk files.

• manage.py
• media
• command
• symlink

Sun 11 Jul 2010 Read More

Email Attachment

Django documentation is lacking in giving an example for sending an email with attachment. Hopefully this code helps those who are trying to send email with attachments

• email
• attachment
• fileinput

Sun 18 Mar 2012 Read More