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Menu/navigation bars in a tag

This tag makes it easy to include menu or navigation bars in an application's pages, even in a 'tabbed' fashion. (The actual appearance is styled in CSS; this example uses UL tags that are then supposed to be styled by a "display: inline" attribute to be rendered as horizontal bars.)

  • tag
  • menu
  • navigation
  • menubar
  • navbar
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Author: ep
  • 4
  • 12

DRY with common model fields

If you have many models that all share the same fields, this might be an option. Please note that order matters: Your model need to inherit from TimestampedModelBase first, and models.Model second. The fields are added directly to each model, e.g. while they will be duplicated on the database level, you only have to define them once in your python code. Not sure if there is a way to automate the call to TimestampedModelInit(). Tested with trunk rev. 5699. There is probably a slight chance that future revisions might break this.

  • models
  • model
  • inheritance
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Natural language date/time form fields

Form fields use the dateutil module [http://labix.org/python-dateutil](http://labix.org/python-dateutil) to parse natural-language input for date and datetime fields. The callback function will replace all date and datetime fields automatically for form_for_model and form_for_instance. **Note**: by replacing the 'form_class' keyword argument instead of just returning the field itself you preserve the 'required' status of the field.

  • newforms
  • datetime
  • date
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email_links

A very basic app centered around a template tag that takes an e-mail address and optional label and returns a link to an e-mail form. This way, you can easily throw e-mail addresses into your template that will automatically link to an e-mail form instead of displaying the e-mail address itself. The model for this app is extremely simple, with only one field to store the e-mail address. When an e-mail is passed to the email_link template tag, the e-mail address is added to the database if it is not already there. This is stored in the database in order to keep the full e-mail address hidden from the viewer. To use, simply create an app called 'email_links' (or you can change the name if you also change line 4 of email_extras.py to reflect the change). Then use the models.py and views.py provided. Add a templatetags directory under your app, and add email_extras.py and a blank __init__.py In your urls.py, add the following to your urlpatterns (subsitute project_name for your own): `(r'^email/(?P<email_id>[0-9]+)/$', 'project_name.email_links.views.email_form'),` Create two templates: email_links/email_form.html and email_links/thanks.html (the examples here are extremely basic - make them however you want). Finally, in a template where you want to provide a link to e-mail someone, first load email_extras: `{% load email_extras %}` Then do one of the following: `{% email_link "[email protected]" %}` `{% email_link "[email protected]" "E-mail someone" %}` Both will create a link to the e-mail form. The first will use mask_email (from the snippet by jkocherhans) to create the link. The second will display the second argument "E-mail someone" in the link. Also note that I've used the Sites add-on to generate the links, but you can easily change this to suit your needs. I hope all of this makes sense. I'm a bit tired, but wanted to get this up before bed.

  • filter
  • tag
  • email
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HttpMethodsMiddleware

This middleware allows developers to "fake" browser support for HTTP methods. Even though most modern browsers only support GET and POST, the HTTP standard defines others. In the context of REST, PUT and DELETE are used for client interaction with the server. For forms with a PUT or DELETE method, this middleware will change them to go through POST, and will include an invisible field called "method_middleware_transform" that carries the originally intended method. So, `<form method="PUT" ...>...</form>` More or less becomes `<form method="POST" ...><input type=hidden name="method_middleware_transform" value="PUT"></form>` (with a few other minor HTML modifications) The process is completely transparent to the developer... you never have to deal with the fact that browsers don't support the standard methods. **One caveat** is that server interaction via `XMLHttpRequest` (AJAX) requires special attention... this middleware won't properly setup your XMLHttpRequest to take advantage of this functionality. This is a combination of the work of Jesse Lovelace and the Django CSRF middleware.

  • middleware
  • rest
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Random-image template tag

This tag makes it easy to have a random rotation of images on a page. Don't forget to set your MEDIA_URL.

  • template
  • image
  • random
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Author: pbx
  • 3
  • 12

Test Django against many Pythons and databases

I'm posting this here mostly because I need a more permanent home for this than my lappy's hard drive. I hope it's interesting to other people, though. Anyway - this script is what I use to test Django against multiple versions of Python and multiple databases. To actually run this you'll of course need Python 2.3, 2.4, and 2.5 installed along with MySQL, PostgreSQL, and sqlite3 -- and the associated database wrappers for all 3 Pythons. Yes, for the record, I've got all those things installed on my laptop. If you can somehow make that work, though, running this script will print out a nice little summary of what's failing against which versions of Python and which database. Run with `-v` to see the actual failures.

  • testing
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Model merging function

Generic function to merge model instances. Useful when you need to merge duplicate models together, e.g. for users. Based on http://djangosnippets.org/snippets/382/, with several enhancements: * *Type checking*: only Model subclasses can be used and testing that all instances are of same model class * *Handles symmetrical many-to-may*: original snippet failed in that case * *Filling up blank attrs of original when duplicate has it filled* * *Prepared to use outside of command-line*

  • django
  • model
  • generic
  • related
  • merge
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Faster pagination / model object seeking (10x faster infact :o) for larger datasets (500k +)

ModelPagination Designed and Coded by Cal Leeming Many thanks to Harry Roberts for giving us a heads up on how to do this properly! ---------------------------------------------------------------------------- This is a super optimized way of paginating datasets over 1 million records. It uses MAX() rather then COUNT(), because this is super faster. EXAMPLE: >>> _t = time.time(); x = Post.objects.aggregate(Max('id')); "Took %ss"%(time.time() - _t ) 'Took 0.00103402137756s' >>> _t = time.time(); x = Post.objects.aggregate(Count('id')); "Took %ss"%(time.time() - _t ) 'Took 0.92404794693s' >>> This does mean that if you go deleting things, then the IDs won't be accurate, so if you delete 50 rows, you're exact count() isn't going to match, but this is okay for pagination, because for SEO, we want items to stay on the original page they were scanned on. If you go deleting items, then the items shift backwards through the pages, so you end up with inconsistent SEO on archive pages. If this doesn't make sense, go figure it out for yourself, its 2am in the morning ffs ;p Now, the next thing we do, is use id seeking, rather then OFFSET, because again, this is a shitton faster: EXAMPLE: >>> _t = time.time(); x = map(lambda x: x, Post.objects.filter(id__gte=400000, id__lt=400500).all()); print "Took %ss"%(time.time() - _t) Took 0.0467309951782s >>> _t = time.time(); _res = map(lambda x: x, Post.objects.all()[400000:400500]); print "Took %ss"%(time.time() - _t) Took 1.05785298347s >>> By using this seeking method (which btw, can be implemented on anything, not just pagination) on a table with 5 million rows, we are saving 0.92s on row count, and 1.01s on item grabbing. This may not seem like much, but if you have 1024 concurrent users, this will make a huge difference. If you have any questions or problems, feel free to contact me on cal.leeming [at] simplicitymedialtd.co.uk

  • model
  • pagination
  • object
  • large
  • big
  • dataset
  • faster
  • optimized
  • quicker
  • seeking
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Generic CSV export admin action factory

**I've since made a better snippet for this: [#2995](http://djangosnippets.org/snippets/2995/)** based on [#1697](http://djangosnippets.org/snippets/1697/) This one is even more generic since you can specify which fields to include or exclude, a custom description text for the drop-down menu and whether to output the header row.

  • csv
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django on tornado

there have been many posts on running django on tornado with static media served by nginx. But for dumb people like me, the whole thing needs to be spelt out. So here is how I succeeded in serving django from a virtual host using nginx and tornado. The key thing to note is that 'root' refers to the **parent** directory of the root and not the full path. Also remember to put in ':' as a line end. Procedure - start the tornado server with the python script on localhost:8888, start nginx. Relax and enjoy your django at the speed of light. Nginx can be got by apt-get or yum, but you need the latest git clone of Tornado - the default tarball does not support django. btw, this install is for FC11 on my laptop - I have done it in production on lenny.

  • nginx
  • tornado
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MultiFormWizard

This is an extended version of the FormWizard which allows display of multiple forms per step and allows usage of ModelForms with initial objects

  • multiple
  • forms
  • form
  • wizzard
  • multi-form-per-step
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Email obfuscation filter using ROT13

An email address obfuscation template filter based on the ROT13 Encryption function in Textmate's HTML bundle. The filter should be applied to a string representing an email address. You can optionally pass the filter an argument that will be used as the email link text (otherwise it will simply use the email address itself). Example usage: {{ email_address|obfuscate:"Contact me!" }} or {{ email_address|obfuscate }} Of course, you can also use this on hardcoded email addresses, like this: {{ "[email protected]"|obfuscate }}

  • filter
  • javascript
  • email
  • textmate
  • obfuscation
  • rot13
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Extended Form Wizard with ability to go backwards

This is an extended version of django wizard with the ability to go back and execute any step directly. To define next step to execute use the form field with the name "wizard_next_step". Don't forget to specify in your form the wizard_max_step field, so the knows the step number with the highest number, where the user was. An other improvement is the variable "wizard_data". It's a QueryDict with data from all wizard forms. It can be used to retrieve values from the field values of the forms from other steps. It could be helpfully for the latest step, where the user should see an overview of his input.

  • forms
  • wizard
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