Prefetch id for Postgresql backend

When uploading a file or image, you need to put it somewhere that's not going to be orphaned by a change in the model. You could use a globally unique value like a uuid, but the django id autofield is a much shorter surrogate field that can be used in a friendly path to the object. The problem with id autofields is that they don't exist when the object is created for the first time - so all files using the id get uploaded to a location 'None' on first save, increasing the likelihood of name collisions. This postgresql only snippet fetches the next id in a way that is safe for concurrent access. This snippet only works on postgresql because neither sqlite or mysql have a nextval equivalent. Instead you would have to lock the table for writes and select the last value inserted incrementing it yourself.

• models
• filefield

Wed 18 Apr 2012 Read More

Encrypted paypal buttons

Function and usage in views and template with django-paypal to have encrypted paypal buttons with a cart(adding multiple elements). All credits go to Jon Atkinson, http://jonatkinson.co.uk/paypal-encrypted-buttons-django/ I just added it here with a complete implementation using a cart(his example didnt include it). I know there is some redundancy in the data passed to the dict and the submit form, i'm just not sure what can i take out, the paypal docs are not clear about it, if you test this code without some of the data and it works, please tell me. The key parts are the cmd _s-xclick and again the cmd '_cart' both are needed.

• paypal
• encrypted button
• cart

Tue 17 Apr 2012 Read More

Modify query string on a url

Modify a query string on a url. The comments in the code should explain sufficiently. String_to_dict, and string_to_list are also useful for templatetags that require variable arguments.

• url
• query

Mon 16 Apr 2012 Read More

RESTful class dispatch

Yet another implementation of class based RESTful dispatch. This particular implementation features: * You do not have to call __init__ from the derived classes. * Avoids __metaclass__ which (in our environment) led to unexpected method override behavior. * Method names match the google webapp API. * One new instance per request to reduce errors in multi-threaded code. Snippets of inspiration: * [436](http://www.djangosnippets.org/snippets/436/) * [437](http://www.djangosnippets.org/snippets/437/) * [1071](http://www.djangosnippets.org/snippets/1071/) * [1072](http://www.djangosnippets.org/snippets/1072/) * [1226](http://www.djangosnippets.org/snippets/1226/)

• views
• rest
• http

Wed 11 Apr 2012 Read More

Custom requests auth class for Tastypie API key authentication

In case you ever use [requests](http://python-requests.org/) (or [slumber](http://slumber.in/)) to do requests against a Tastypie API that requires API key authentication, this small custom auth class will help you. Use it like that (with requests): auth = TastypieApiKeyAuth('jezdez', '25fdd0d9d210acb78b5b845fe8284a3c93630252') response = requests.get('http://api.foo.bar/v1/spam/', auth=auth) or with slumber: auth = TastypieApiKeyAuth('jezdez', '25fdd0d9d210acb78b5b845fe8284a3c93630252') api = slumber.API("http://api.foo.bar/v1/", auth=auth) spam = api.spam().get()

• api
• auth
• tastypie

Wed 11 Apr 2012 Read More

Django Sudo

Staff can log in as a user, from a url to help with customer support or debugging.

• admin
• user
• login
• staff
• sudo

Mon 09 Apr 2012 Read More

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

Mon 09 Apr 2012 Read More

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

Mon 09 Apr 2012 Read More

Include captchas from recaptcha.net

Recaptcha is a free service that helps you protect your forms against spam bots by displaying a picture showing 2 words or playing an audio file telling 8 digits for the visually handicapped. After registration on http://recaptcha.net a private and a public key are generated. Put the keys in settings.py. Find client code for recaptcha at http://pypi.python.org/pypi/recaptcha-client. Put the file captcha.py into application root.

• captcha
• recaptcha

Sun 08 Apr 2012 Read More

Mixin for named URL WizardViews with one form on the frontpage

A Django 1.4 wizard mixin for use cases with a wizard step on the frontpage of your site -- with a request path of `'/'`. Just define the name of the step (e.g. `root_step = 'landing_page'`) and it does the setup and redirection automatically.

• forms
• wizard

Wed 04 Apr 2012 Read More

Very simple email image embed

This is a simple way to embed images in emails, rather than use absolute links, which many clients will not show by default. It has not undergone extensive testing but it should get you started. Comments / suggestions welcome.

• image
• email
• embed
• mime

Wed 04 Apr 2012 Read More

Django enumeration for model field choices

The problem with supplying a Django model field with choices parameter is the way you check a value of that field in an object. You do nasty things like this: if model_instance.choice_field == 1: The problem of getting rid of hard-coded numbers is recognized over the internet, but I haven't found any short and understandable solution. Basically, we need a enumeration in python, that is ok to use as the Django `choices` model field argument. I've seen a couple of solutions of DjangoSnippets. Mine is shorter and easier because it only works for integer field choices.

• choices
• integer
• enumeration

Mon 02 Apr 2012 Read More

MultiSelectField

This field provides a multi select choice field.

• fields
• orm

Sat 31 Mar 2012 Read More

Database template loader

This snippet provides getting templates from the model in database. We work with templates as usual (using as a template name value of the field **"slug"**). You can do your own application without "TemplateTypes" model - it's added for ability to filter templates. You can use choices or remove "template_type" field and "TemplateTypes" model at all. For ease of editing, you can connect all this to the admin interface, adding to the field "template_body" widget with syntax highlighting (I used [CodeMirror](http://codemirror.net/)).

• templates
• template loader

Fri 30 Mar 2012 Read More

Middleware to prevent access to the admin when user ip not in INTERNAL_IPS

This middleware will prevent access to the admin if the users IP isn't in the INTERNAL_IPS setting, by comparing the request path with the reversed index URL of the default admin site, ultimately raising a 404 (unless DEBUG = True).

• middleware
• admin

Thu 29 Mar 2012 Read More