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Code Snippets


Calling Django from Scons 

Note I've updated this recently. It only works using Django > 0.95 


# UPDATE - this has gotten easier as of Django 0.95 (Magic Removal)

from django.conf import settings as django_settings

MODULE_HOME = path.dirname('.')

template_dirs = (
    path.join(MODULE_HOME, 'templates'), 
)

django_settings.configure(DEBUG=True, 
        TEMPLATE_DEBUG=True,
        TEMPLATE_DIRS=template_dirs,
)

from django.template import Context, Template
from django.template import loader


""" run django templates"""
def run_django(target, source, env):
    """ runs a django template, given target and source and dict of values"""
    input_file = str(source[0]).encode('utf-8')
    output_file = str(target[0]).encode('utf-8')
    
    t = Template(open(input_file).read())
    # FIXME: could use this
    #django.template.loader.get_template(template_name)

    c = Context(env['context'])

    outfile = file(output_file, 'w')
    outfile.write(t.render(c))
    outfile.close()
    return None
       
django = Builder(action = run_django, suffix='.html', src_suffix='.html')

env = Environment(ENV = {'PATH' : os.environ['PATH']},
                          BUILDERS = {'Django' : django}
                          )

index_context = {"current_page": "default"}
index = env.Django(source="templates/default.html",target="site/default.html",context=index_context)

env.Alias("index", index)
env.Default("index")

09/13/06

Keeping a log of updates to records in Django 

I had the task of creating an RSS feed for wiki items as they are updated. I figured I would just use Django's post_save method. But then there was the classic chicken/egg problem. Luckily Django has the undocumented replaces_module meta attribute.

2/14/2007: I've changed this recently. After the "magic-removal" branch - this was much easier. So this only works for Django >= 0.95 and the replaces_module is no longer used. In fact that makes this bit of code trivial and typical, but I'm leaving it here anyway 


from django.db import models
import datetime

class Tag(models.Model):
    """Tag (subject) of a Wikipage"""

    name = models.SlugField(maxlength=75)

    class Admin:
        pass

    class Meta:
        db_table = "wiki_tags"

    def __str__(self):
        return self.name


class Wikihistory(models.Model):
    """Wiki History for RSS"""

    wikipage = models.ForeignKey("Wikipage",db_column="wiki_page_id")
    created_at = models.DateTimeField(auto_now_add=True)

    class Admin:
        pass

    class Meta:
        db_table = "wiki_history"

    def __str__(self):
        if self.wikipage:
            return self.wikipage.title + " " + self.created_at.strftime("%m/%d/%y %I:%M %p")
        else:
            return self.created_at

    def get_absolute_url(self):
        date_formatted = self.created_at.strftime("%Y%m%d:%I:%M:%p")

        if self.wikipage:
            return "/wiki/view/%s" % (self.wikipage.title)
        else:
            return ""

class Wikipage(models.Model):
    """Wiki page"""

    title = models.CharField(maxlength=75)
    content = models.TextField(null=True,blank=True)
    
    tags = models.ManyToManyField(Tag,null=True,blank=True)

    class Admin:
        pass

    class Meta:
        db_table = "wiki_wikipages"

    def first_letter(self):
        return self.title[0].upper()

    def __str__(self):
        return self.title
    
    def save(self):
        super(Wikipage, self).save()
        entry = Wikihistory(wikipage=self)
        entry.save()

    def get_absolute_url(self):
        return "/wiki/%s/" % self.title

02/14/07