I'm trying to make this table with a clickable field which changes the boolean for the entry to its opposite value. It works, but I want an alternative text as "False" or "True" does not look nice, and the users are mainly Norwegian.
def bool_to_norwegian(boolean):
if boolean:
return "Ja"
else:
return "Nei"
class OrderTable(tables.Table):
id = tables.LinkColumn('admin_detail', args=[A('id')])
name = tables.Column()
address = tables.Column()
order = tables.Column()
order_placed_at = tables.DateTimeColumn()
order_delivery_at = tables.DateColumn()
price = tables.Column()
comment = tables.Column()
sent = tables.LinkColumn('status_sent', args=[A('id')])
paid = tables.LinkColumn('status_paid', args=[A('id')], text=[A('paid')])
class Meta:
attrs = {'class': 'order-table'}
If you look under the "paid" entry I am testing this right now, why can't I access the data with the same accessor as I do in the args? If I change the args to args=[A('paid')] and look at the link, it does indeed have the correct data on it. The model names are the same as the ones in this table, and "paid" and "sent" are BooleanFields.
This is kind of what I ultimately want:
text=bool_to_norwegian([A('paid')])
Here is what I send to the table:
orders = Order.objects.order_by("-order_delivery_at")
orders = orders.values()
table = OrderTable(orders)
RequestConfig(request).configure(table)
The text argument expects a callable that accepts a record, and returns a text value. You are passing it a list (which it will just ignore), and your function is expecting a boolean instead of a record. There is also no need for using accessors here.
Something like this should work:
def bool_to_norwegian(record):
if record.paid:
return "Ja"
else:
return "Nei"
Then in your column:
paid = tables.LinkColumn('status_paid', text=bool_to_norwegian)
(Note, it is not clear from your question where the data is coming from - is paid a boolean? You may need to adjust this to fit).
As an aside, the way you are passing args to your columns is weird (it seems the documentation also recommends this, but I don't understand why - it's very confusing). A more standard approach would be:
id = tables.LinkColumn('admin_detail', A('id'))
or using named arguments:
id = tables.LinkColumn('admin_detail', accessor=A('id'))
Related
Model:
db.define_table('orders',
Field('customer_id', db.customer)
Field('order_id', 'string')
)
I want to get a special order_id like XY-150012 where XY is part of the customer name, 15 is the year and 12 the id the actual record-id of orders. I tried in the model:
db.orders.order_id.compute = lambda r: "%s-%s00%s" % (db.customer(r['customer_id']).short, str(request.now.year)[2:], r['id'])
The id is never recognized, the computation ends up as None. If I remove r['id'] from the compute-line it works.
EDIT:
After adding an extra field field('running_number', 'integer') to the model I can access this fields content.
Is there a easy way to set this fields default=db.orders.id?
SOLUTION:
With Anthony´s Input, and reading about recursive selects I came up with this solution:
db.define_table('orders',
Field('customer_id', db.customer),
Field('order_id', 'string', default = None))
def get_order_id(id, short):
y = str(request.now.year)[2:]
return '%s-%s00%s' % (short, y, id)
def set_id_after_insert(fields,id):
fields.update(id=id)
def set_order_id_after_update(s,f):
row = s.select().first()
if row['order_id'] == None:
s.update_naive(order_id=get_order_id(row['id'], row['customer_id'].short)
else:
return
db.orders._after_insert.append(lambda f,id: set_id_after_insert(f,id))
db.orders._after_update.append(lambda s,f: set_order_id_after_update(s,f))
The problem is that the record ID is not known until after the record has been inserted in the database, as the id field is an auto-incrementing integer field whose value is generated by the database, not by web2py.
One option would be to define an _after_insert callback that updates the order_id field after the insert:
def order_after_insert(fields, id):
fields.update(id=id)
db(db.order.id == id).update(order_id=db.order.order_id.compute(fields))
db.order._after_insert.append(order_after_insert)
You might also want to create an _after_update callback, but in that case, be sure to use the update_naive argument in both callbacks when defining the Set (see above link for details).
Depending on how the order_id is used, another option might be a virtual field.
I am using Redis Object Mapper(ROM) here.
This is my model
class User(rom.Model):
name = rom.String(required=True, unique=True)
nickname = rom.String(required=False)
photo = rom.String(required=False)
I am trying -
user1 = User(name="Ankush", nickname="iamkhush",
photo='http://graph.facebook.com/iamkhush/picture')
user1.save()
I get the result when I do
user = User.get(1) #user is a model instance
But when I do
user_obj = User.query.filter(name='Ankush').execute()
I get [ ] (An empty result)
Cant get why is this happening?
There are two parts to this. First, you don't need to use the index if you want to get an item by a column defined with unique=True, but the query is different. Using unique=True and index=False, you can get the item by using the User.get_by() form:
>>> User.get_by(name="Ankush")
<__main__.User object at 0x87070cc>
The primary limitation being that you must pass the full column exactly as it is defined in the column. This is generally useful for keeping unique email addresses (lowercase them first!), usernames (be careful with your capitalization), and other examples.
The second part is that when enabling the index, the index has "case-insensitive unique bag-of-words" semantics for string/text columns (I come from the search engine side of the world, which has substantially different (and arguably better) semantics than typical db queries). So if you want to find entries, you need to use:
>>> class User(rom.Model):
... name = rom.String(required=True, unique=True, index=True)
... nickname = rom.String(required=False)
... photo = rom.String(required=False)
...
>>> user1 = User(name="Ankush", nickname="iamankush", photo="http://graph.facebook.com/iamkhush/picture")
>>> user1.save()
>>> User.query.filter(name="ankush").all()
[<__main__.User object at 0x870738c>]
(also note that .execute() is an alias for .all() ).
If you want to change the case-sensitivity or other behavior with columns defined with index=True, you need to pass a custom keygen argument (you can see rom.util._string_keygen() at https://github.com/josiahcarlson/rom/blob/master/rom/util.py#L149 for rom.String and rom.Text key generation semantics).
You need to pass index=True along with name to allow it to be queried by filter.
class User(rom.Model):
name = rom.Text(required=True, unique=True,index = True,keygen=text_keyge)
nickname = rom.String(required=False)
photo = rom.String(required=False)
I have a django model that looks something like this:
class Definition
name = models.CharField(max_length=254)
text = models.TextField()
If I do the following query:
animal = Definition.objects.get(name='Owl')
and if I have the following definitions with these names in my database:
Elephant, Owl, Zebra, Human
is there a way to do a django query(ies) that will show me the previous and the next Definitions based on the animal object based on alphabetical order of the name field in the model?
I know that there are ways of getting previous/next based on datetime fields, but I am not so sure for this case.
I don't know of any way of doing this in less than three queries.
target = 'Owl'
animal = Definition.objects.get(name=target)
previous_animal = Definition.objects.order_by('name').filter(name__lt=target)[0]
next_animal = Definition.objects.order_by('name').filter(name__gt=target)[0]
If anyone comes across this like I just did...
heres my solution... it also loops(so if on last item it shows first item as next and if on first item shows last item as previous)
def get_previous_by_title(self):
curr_title = self.get_object().title
queryset = self.my_queryset()
try:
prev = queryset.filter(title__lt=curr_title).order_by("-title")[0:1].get()
except Video.DoesNotExist:
prev = queryset.order_by("-title")[0:1].get()
return prev
def get_next_by_title(self):
curr_title = self.get_object().title
queryset = self.my_queryset()
try:
next = queryset.filter(title__gt=curr_title).order_by("title")[0:1].get()
except Video.DoesNotExist:
next = queryset.order_by("title")[0:1].get()
return next
i have custom querysets based on user level so could just set the queryset as a normal queryset like... Video.objects.all() but anyplace I repeat code more than once I make a function
I was wondering if there was a way to use Django's filter() on query sets using a dynamically generated python property using property(). I have first_name and last_name of every user, and I want to filter based on their concatenated name first_name last_name. (The reason behind this is that when I do autocomplete I search to see if the query matches first name, last name, or part of the concatenation. I want John S to match John Smith, for example.
I created a property of name:
def _get_name(self):
return self.first_name + " " + self.last_name
name = property(_get_name)
This way I can call user.name to get the concatenated name.
However, if I try to do User.objects.filter(name__istartswith=query) I get the error Cannot resolve keyword 'name' into field.
Any ideas on how to do this? Do I have to create another field in the database to store the full name?
The accepted answer is not entirely true.
For many cases, you can override get() in the model manager to pop dynamic properties from the keyword arguments, then add the actual attributes you want to query against into the kwargs keyword arguments dictionary. Be sure to return a super so any regular get() calls return the expected result.
I'm only pasting my own solution, but for the __startswith and other conditional queries you could add some logic to split the double-underscore and handle appropriately.
Here was my work-around to allow querying by a dynamic property:
class BorrowerManager(models.Manager):
def get(self, *args, **kwargs):
full_name = kwargs.pop('full_name', None)
# Override #1) Query by dynamic property 'full_name'
if full_name:
names = full_name_to_dict(full_name)
kwargs = dict(kwargs.items() + names.items())
return super(BorrowerManager, self).get(*args, **kwargs)
In models.py:
class Borrower(models.Model):
objects = BorrowerManager()
first_name = models.CharField(null=False, max_length=30)
middle_name = models.CharField(null=True, max_length=30)
last_name = models.CharField(null=False, max_length=30)
created = models.DateField(auto_now_add=True)
In utils.py (for the sake of context):
def full_name_to_dict(full_name):
ret = dict()
values = full_name.split(' ')
if len(values) == 1:
raise NotImplementedError("Not enough names to unpack from full_name")
elif len(values) == 2:
ret['first_name'] = values[0]
ret['middle_name'] = None
ret['last_name'] = values[1]
return ret
elif len(values) >= 3:
ret['first_name'] = values[0]
ret['middle_name'] = values[1:len(values)-1]
ret['last_name'] = values[len(values)-1]
return ret
raise NotImplementedError("Error unpacking full_name to first, middle, last names")
filter() operates on the database level (it actually writes SQL), so it won't be possible to use it for any queries based on your python code (dynamic property in your question).
This is an answer put together from many other answers in this department : )
I had a similar problem and was looking for solution. Taking for granted that a search engine would be the best option (e.g. django-haystack with Elasticsearch), that's how I would implement some code for your needs using only the Django ORM (you can replace icontains with istartswith):
from django.db.models import Value
from django.db.models.functions import Concat
queryset = User.objects.annotate(full_name=Concat('first_name', Value(' '), 'last_name')
return queryset.filter(full_name__icontains=value)
In my case I didn't know whether the user would insert 'first_name last_name' or viceversa, so I used the following code.
from django.db.models import Q, Value
from django.db.models.functions import Concat
queryset = User.objects.annotate(first_last=Concat('first_name', Value(' '), 'last_name'), last_first=Concat('last_name', Value(' '), 'first_name'))
return queryset.filter(Q(first_last__icontains=value) | Q(last_first__icontains=value))
With Django <1.8, you would probably need to resort to extra with the SQL CONCAT function, something like the following:
queryset.extra(where=['UPPER(CONCAT("auth_user"."last_name", \' \', "auth_user"."first_name")) LIKE UPPER(%s) OR UPPER(CONCAT("auth_user"."first_name", \' \', "auth_user"."last_name")) LIKE UPPER(%s)'], params=['%'+value+'%', '%'+value+'%'])
Think it's not possible in django to filter on properties that does not present as a database filed, but what you can do to make cool autocomplete search is something like this:
if ' ' in query:
query = query.split()
search_results = list(chain(User.objects.filter(first_name__icontains=query[0],last_name__icontains=query[1]),
User.objects.filter(first_name__icontains=query[1],last_name__icontains=query[0])))
else:
search_results = User.objects.filter(Q(first_name__icontains=query)| Q(last_name__icontains=query))
This code gives the user of your system a flexibility to start typing either first name or last name and the user will be thankful to you for allowing this.
I want to create a new type of field for django models that is basically a ListOfStrings. So in your model code you would have the following:
models.py:
from django.db import models
class ListOfStringsField(???):
???
class myDjangoModelClass():
myName = models.CharField(max_length=64)
myFriends = ListOfStringsField() #
other.py:
myclass = myDjangoModelClass()
myclass.myName = "bob"
myclass.myFriends = ["me", "myself", "and I"]
myclass.save()
id = myclass.id
loadedmyclass = myDjangoModelClass.objects.filter(id__exact=id)
myFriendsList = loadedclass.myFriends
# myFriendsList is a list and should equal ["me", "myself", "and I"]
How would you go about writing this field type, with the following stipulations?
We don't want to do create a field which just crams all the strings together and separates them with a token in one field like this. It is a good solution in some cases, but we want to keep the string data normalized so tools other than django can query the data.
The field should automatically create any secondary tables needed to store the string data.
The secondary table should ideally have only one copy of each unique string. This is optional, but would be nice to have.
Looking in the Django code it looks like I would want to do something similar to what ForeignKey is doing, but the documentation is sparse.
This leads to the following questions:
Can this be done?
Has it been done (and if so where)?
Is there any documentation on Django about how to extend and override their model classes, specifically their relationship classes? I have not seen a lot of documentation on that aspect of their code, but there is this.
This is comes from this question.
There's some very good documentation on creating custom fields here.
However, I think you're overthinking this. It sounds like you actually just want a standard foreign key, but with the additional ability to retrieve all the elements as a single list. So the easiest thing would be to just use a ForeignKey, and define a get_myfield_as_list method on the model:
class Friends(model.Model):
name = models.CharField(max_length=100)
my_items = models.ForeignKey(MyModel)
class MyModel(models.Model):
...
def get_my_friends_as_list(self):
return ', '.join(self.friends_set.values_list('name', flat=True))
Now calling get_my_friends_as_list() on an instance of MyModel will return you a list of strings, as required.
What you have described sounds to me really similar to the tags.
So, why not using django tagging?
It works like a charm, you can install it independently from your application and its API is quite easy to use.
I also think you're going about this the wrong way. Trying to make a Django field create an ancillary database table is almost certainly the wrong approach. It would be very difficult to do, and would likely confuse third party developers if you are trying to make your solution generally useful.
If you're trying to store a denormalized blob of data in a single column, I'd take an approach similar to the one you linked to, serializing the Python data structure and storing it in a TextField. If you want tools other than Django to be able to operate on the data then you can serialize to JSON (or some other format that has wide language support):
from django.db import models
from django.utils import simplejson
class JSONDataField(models.TextField):
__metaclass__ = models.SubfieldBase
def to_python(self, value):
if value is None:
return None
if not isinstance(value, basestring):
return value
return simplejson.loads(value)
def get_db_prep_save(self, value):
if value is None:
return None
return simplejson.dumps(value)
If you just want a django Manager-like descriptor that lets you operate on a list of strings associated with a model then you can manually create a join table and use a descriptor to manage the relationship. It's not exactly what you need, but this code should get you started.
Thanks for all those that answered. Even if I didn't use your answer directly the examples and links got me going in the right direction.
I am not sure if this is production ready, but it appears to be working in all my tests so far.
class ListValueDescriptor(object):
def __init__(self, lvd_parent, lvd_model_name, lvd_value_type, lvd_unique, **kwargs):
"""
This descriptor object acts like a django field, but it will accept
a list of values, instead a single value.
For example:
# define our model
class Person(models.Model):
name = models.CharField(max_length=120)
friends = ListValueDescriptor("Person", "Friend", "CharField", True, max_length=120)
# Later in the code we can do this
p = Person("John")
p.save() # we have to have an id
p.friends = ["Jerry", "Jimmy", "Jamail"]
...
p = Person.objects.get(name="John")
friends = p.friends
# and now friends is a list.
lvd_parent - The name of our parent class
lvd_model_name - The name of our new model
lvd_value_type - The value type of the value in our new model
This has to be the name of one of the valid django
model field types such as 'CharField', 'FloatField',
or a valid custom field name.
lvd_unique - Set this to true if you want the values in the list to
be unique in the table they are stored in. For
example if you are storing a list of strings and
the strings are always "foo", "bar", and "baz", your
data table would only have those three strings listed in
it in the database.
kwargs - These are passed to the value field.
"""
self.related_set_name = lvd_model_name.lower() + "_set"
self.model_name = lvd_model_name
self.parent = lvd_parent
self.unique = lvd_unique
# only set this to true if they have not already set it.
# this helps speed up the searchs when unique is true.
kwargs['db_index'] = kwargs.get('db_index', True)
filter = ["lvd_parent", "lvd_model_name", "lvd_value_type", "lvd_unique"]
evalStr = """class %s (models.Model):\n""" % (self.model_name)
evalStr += """ value = models.%s(""" % (lvd_value_type)
evalStr += self._params_from_kwargs(filter, **kwargs)
evalStr += ")\n"
if self.unique:
evalStr += """ parent = models.ManyToManyField('%s')\n""" % (self.parent)
else:
evalStr += """ parent = models.ForeignKey('%s')\n""" % (self.parent)
evalStr += "\n"
evalStr += """self.innerClass = %s\n""" % (self.model_name)
print evalStr
exec (evalStr) # build the inner class
def __get__(self, instance, owner):
value_set = instance.__getattribute__(self.related_set_name)
l = []
for x in value_set.all():
l.append(x.value)
return l
def __set__(self, instance, values):
value_set = instance.__getattribute__(self.related_set_name)
for x in values:
value_set.add(self._get_or_create_value(x))
def __delete__(self, instance):
pass # I should probably try and do something here.
def _get_or_create_value(self, x):
if self.unique:
# Try and find an existing value
try:
return self.innerClass.objects.get(value=x)
except django.core.exceptions.ObjectDoesNotExist:
pass
v = self.innerClass(value=x)
v.save() # we have to save to create the id.
return v
def _params_from_kwargs(self, filter, **kwargs):
"""Given a dictionary of arguments, build a string which
represents it as a parameter list, and filter out any
keywords in filter."""
params = ""
for key in kwargs:
if key not in filter:
value = kwargs[key]
params += "%s=%s, " % (key, value.__repr__())
return params[:-2] # chop off the last ', '
class Person(models.Model):
name = models.CharField(max_length=120)
friends = ListValueDescriptor("Person", "Friend", "CharField", True, max_length=120)
Ultimately I think this would still be better if it were pushed deeper into the django code and worked more like the ManyToManyField or the ForeignKey.
I think what you want is a custom model field.