fisclimate#1348: Add column attributes

readme.rst

@@ -38,3 +38,30 @@ Current Status
 ---------------
 
 Currently beta quality.
+
+Changes in 0.2.0
+----------------
+
+This update includes backwards-incompatible changes that affect the way column classes
+are defined.
+
+From this point forward, column classes should declare their pertinent configuration options
+via class attributes, rather than as initialization parameters.
+
+Pre-0.2.0:
+
+ class SomeColumn(Column):
+ def __init__(self, label, key=None, filter=None, can_sort=False,
+ link_label=None, xls_width=None, xls_style=None, xls_num_format=None,
+ render_in=_None, **kwargs):
+ Column.__init__(self, label, key, filter, can_sort, xls_width,
+ xls_style, xls_num_format, render_in, **kwargs)
+ self.link_label = link_label
+
+
+The equivalent code, beginning in 0.2.0:
+
+ class SomeColumn(Column):
+ can_sort = False
+ link_label = None
+

webgrid/__init__.py

@@ -17,6 +17,10 @@
 from werkzeug.datastructures import MultiDict
 
 from .renderers import HTML, XLS
+from .utils import (
+ enumerate_class_attributes,
+ OverridableAttributeProperty
+)
 
 # conditional imports to support libs without requiring them
 try:
@@ -36,7 +40,7 @@
 
 class _None(object):
  """
- A sentinal object to indicate no value
+ A sentinel object to indicate no value
  """
  pass
 
@@ -93,10 +97,16 @@ class Column(object):
  Column represents the fixed settings for a datagrid column
  """
  _creation_counter = 0
+
+ # NOTE: `key` and `render_in` have some property magic going on below
+ key = None
+ filter = None
+ can_sort = True
  xls_width = None
- xls_num_format = None
  xls_style = None
- render_in = 'html', 'xls'
+ xls_num_format = None
+ render_in = ('html', 'xls')
+ has_subtotal = False
 
  def __new__(cls, *args, **kwargs):
  col_inst = super(Column, cls).__new__(cls)
@@ -109,55 +119,70 @@ def _assign_to_grid(self):
  grid_cls_cols = grid_locals.setdefault('__cls_cols__', [])
  grid_cls_cols.append(self)
 
- def __init__(self, label, key=None, filter=None, can_sort=True,
- xls_width=None, xls_style=None, xls_num_format=None,
- render_in=_None, has_subtotal=False, **kwargs):
+ def __init__(self, label, key=_None, filter=_None, **kwargs):
+
  self.label = label
- self.key = key
- self.filter = filter
- self.filter_for = None
- self.filter_op = None
- self._create_order = False
- self.can_sort = can_sort
- self.has_subtotal = has_subtotal
+ self.expr = None
+
+ for attr in enumerate_class_attributes(self):
+ if attr in kwargs:
+ setattr(self, attr, kwargs.pop(attr))
+
+ if key is not _None:
+ self.key = key
+
+ if filter is not _None:
+ self.filter = filter
+
  self.kwargs = kwargs
  self.grid = None
+
+ # filters can be sent in as a class (not class instance) if needed
+ if inspect.isclass(self.filter):
+ if self.expr is None:
+ raise ValueError('the filter was a class type, but no'
+ ' column-like object is available from "key" to pass in as'
+ ' as the first argument')
+ self.filter = self.filter(self.expr)
+
+ key = OverridableAttributeProperty('key', key)
+
+ @key.setter
+ def key(self, name, value):
  self.expr = None
- if render_in is not _None:
- self.render_in = ensure_tuple(render_in)
- if xls_width:
- self.xls_width = xls_width
- if xls_num_format:
- self.xls_num_format = xls_num_format
- if xls_style:
- self.xls_style = xls_style
 
  # if the key isn't a base string, assume its a column-like object that
  # works with a SA Query instance
- if key is None:
+ if value is None:
  self.can_sort = False
- elif not isinstance(key, six.string_types):
- self.expr = col = key
+
+ elif isinstance(value, six.string_types):
+ pass
+
+ else:
+ self.expr = value
+
  # use column.key, column.name, or None in that order
- key = getattr(col, 'key', getattr(col, 'name', None))
+ key = getattr(value, 'key', getattr(value, 'name', None))
 
  if key is None:
  raise ValueError('expected filter to be a SQLAlchemy column-like'
  ' object, but it did not have a "key" or "name"'
  ' attribute')
- self.key = key
 
- # filters can be sent in as a class (not class instance) if needed
- if inspect.isclass(filter):
- if self.expr is None:
- raise ValueError('the filter was a class type, but no'
- ' column-like object is available from "key" to pass in as'
- ' as the first argument')
- self.filter = filter(self.expr)
+ value = key
+
+ setattr(self, name, value)
+
+ render_in = OverridableAttributeProperty('render_in', render_in)
+
+ @render_in.setter
+ def render_in(self, name, value):
+ setattr(self, name, ensure_tuple(value))
 
  def new_instance(self, grid):
  cls = self.__class__
- column = cls(self.label, self.key, None, self.can_sort, _dont_assign=True)
+ column = cls(self.label, self.key, None, can_sort=self.can_sort, _dont_assign=True)
  column.grid = grid
  column.expr = self.expr
 
@@ -173,13 +198,10 @@ def new_instance(self, grid):
  else:
  column.xlwt_stymat = None
 
- # try to be smart about which attributes should get copied to the
- # new instance by looking for attributes on the class that have the
- # same name as arguments to the classes __init__ method
- for argname in inspect.getargspec(self.__init__).args:
- if argname != 'self' and hasattr(self, argname) and \
- argname not in ('label', 'key', 'filter', 'can_sort'):
- setattr(column, argname, getattr(self, argname))
+ # copy the class attributes to the newly-instantiated column
+ for attr in enumerate_class_attributes(self):
+ if attr not in ('can_sort', 'filter', 'key', 'label'):
+ setattr(column, attr, getattr(self, attr))
 
  return column
 
@@ -274,13 +296,7 @@ def xlwt_stymat_calc(self, value):
 
 class LinkColumnBase(Column):
  link_attrs = {}
-
- def __init__(self, label, key=None, filter=None, can_sort=True,
- link_label=None, xls_width=None, xls_style=None, xls_num_format=None,
- render_in=_None, **kwargs):
- Column.__init__(self, label, key, filter, can_sort, xls_width,
- xls_style, xls_num_format, render_in, **kwargs)
- self.link_label = link_label
+ link_label = None
 
  def render_html(self, record, hah):
  url = self.create_url(record)
@@ -295,16 +311,9 @@ def create_url(self, record):
 
 
 class BoolColumn(Column):
-
- def __init__(self, label, key_or_filter=None, key=None, can_sort=True,
- reverse=False, true_label='True', false_label='False',
- xls_width=None, xls_style=None, xls_num_format=None,
- render_in=_None, **kwargs):
- Column.__init__(self, label, key_or_filter, key, can_sort, xls_width,
- xls_style, xls_num_format, render_in, **kwargs)
- self.reverse = reverse
- self.true_label = true_label
- self.false_label = false_label
+ false_label = 'False'
+ reverse = False
+ true_label = 'True'
 
  def format_data(self, data):
  if self.reverse:
@@ -315,23 +324,12 @@ def format_data(self, data):
 
 
 class YesNoColumn(BoolColumn):
-
- def __init__(self, label, key_or_filter=None, key=None, can_sort=True,
- reverse=False, xls_width=None, xls_style=None, xls_num_format=None,
- render_in=_None, **kwargs):
- BoolColumn.__init__(self, label, key_or_filter, key, can_sort, reverse,
- 'Yes', 'No', xls_width, xls_style, xls_num_format, render_in, **kwargs)
+ false_label = 'No'
+ true_label = 'Yes'
 
 
 class DateColumnBase(Column):
-
- def __init__(self, label, key_or_filter=None, key=None, can_sort=True,
- html_format=None, xls_width=None, xls_style=None, xls_num_format=None,
- render_in=_None, **kwargs):
- Column.__init__(self, label, key_or_filter, key, can_sort, xls_width,
- xls_style, xls_num_format, render_in, **kwargs)
- if html_format:
- self.html_format = html_format
+ html_format = None
 
  def render_html(self, record, hah):
  data = self.extract_and_format_data(record)
@@ -387,28 +385,19 @@ class TimeColumn(DateColumnBase):
 
 
 class NumericColumn(Column):
+ curr = ''
+ dp = '.'
+ format_as = 'general'
+ neg = '-'
+ places = 2
+ pos = ''
+ sep = ','
+ trailneg = ''
  xls_fmt_general = '#,##0{dec_places};{neg_prefix}-#,##0{dec_places}'
  xls_fmt_accounting = '_($* #,##0{dec_places}_);{neg_prefix}_($* (#,##0{dec_places})' + \
  ';_($* "-"??_);_(@_)'
  xls_fmt_percent = '0{dec_places}%;{neg_prefix}-0{dec_places}%'
-
- def __init__(self, label, key_or_filter=None, key=None, can_sort=True,
- reverse=False, xls_width=None, xls_style=None, xls_num_format=None,
- render_in=_None, format_as='general', places=2, curr='',
- sep=',', dp='.', pos='', neg='-', trailneg='',
- xls_neg_red=True, has_subtotal=False, **kwargs):
- Column.__init__(self, label, key_or_filter, key, can_sort, xls_width,
- xls_style, xls_num_format, render_in,
- has_subtotal, **kwargs)
- self.places = places
- self.curr = curr
- self.sep = sep
- self.dp = dp
- self.pos = pos
- self.neg = neg
- self.trailneg = trailneg
- self.xls_neg_red = xls_neg_red
- self.format_as = format_as
+ xls_neg_red = True
 
  def html_decimal_format_opts(self, data):
  return (