import os
from decimal import Decimal
from datetime import datetime
from dojango.conf import settings # using the app-specific settings
from django.core.serializers.json import DateTimeAwareJSONEncoder
from django.db.models import Model
from django.db.models.query import QuerySet
from django.http import HttpResponse
from django.utils import simplejson as json
from django.utils.encoding import force_unicode
from django.utils.functional import Promise
def debug(request):
"Returns context variables helpful for debugging."
context_extras = {}
if settings.DEBUG:
context_extras['DEBUG'] = True
return context_extras
def json_encode(data):
"""
The main issues with django's default json serializer is that properties that
had been added to an object dynamically are being ignored (and it also has
problems with some models).
"""
def _any(data):
ret = None
# Opps, we used to check if it is of type list, but that fails
# i.e. in the case of django.newforms.utils.ErrorList, which extends
# the type "list". Oh man, that was a dumb mistake!
if isinstance(data, list):
ret = _list(data)
# Same as for lists above.
elif isinstance(data, dict):
ret = _dict(data)
elif isinstance(data, Decimal):
# json.dumps() cant handle Decimal
ret = str(data)
elif isinstance(data, QuerySet):
# Actually its the same as a list ...
ret = _list(data)
elif isinstance(data, Model):
ret = _model(data)
# here we need to encode the string as unicode (otherwise we get utf-16 in the json-response)
elif isinstance(data, basestring):
ret = unicode(data)
# see http://code.djangoproject.com/ticket/5868
elif isinstance(data, Promise):
ret = force_unicode(data)
elif isinstance(data, datetime):
# For dojo.date.stamp we convert the dates to use 'T' as separator instead of space
# i.e. 2008-01-01T10:10:10 instead of 2008-01-01 10:10:10
ret = str(data).replace(' ', 'T')
else:
ret = data
return ret
def _model(data):
ret = {}
# If we only have a model, we only want to encode the fields.
for f in data._meta.fields:
ret[f.attname] = _any(getattr(data, f.attname))
# And additionally encode arbitrary properties that had been added.
fields = dir(data.__class__) + ret.keys()
add_ons = [k for k in dir(data) if k not in fields]
for k in add_ons:
ret[k] = _any(getattr(data, k))
return ret
def _list(data):
ret = []
for v in data:
ret.append(_any(v))
return ret
def _dict(data):
ret = {}
for k,v in data.items():
ret[k] = _any(v)
return ret
ret = _any(data)
return json.dumps(ret, cls=DateTimeAwareJSONEncoder)
def json_response(data):
data = json_encode(data)
mimetype = "text/json"
ret = HttpResponse(data, mimetype=mimetype+"; charset=%s" % settings.DEFAULT_CHARSET)
# The following are for IE especially
ret['Pragma'] = "no-cache"
ret['Cache-Control'] = "must-revalidate"
ret['If-Modified-Since'] = str(datetime.now())
return ret
def to_dojo_data(items, identifier='id', num_rows=None):
"""Return the data as the dojo.data API defines.
The dojo.data API expects the data like so:
{identifier:"whatever",
items: [
{name:"Lenin", id:3, ....},
]
}
The identifier is optional.
"""
ret = {'items':items}
if identifier:
ret['identifier'] = identifier
if num_rows:
ret['numRows'] = num_rows
return ret
def is_number(s):
"""Is this the right way for checking a number.
Maybe there is a better pythonic way :-)"""
try:
int(s)
return True
except TypeError:
pass
except ValueError:
pass
return False
e-REdING. Biblioteca de la Escuela Superior de Ingenieros de Sevilla.
