1#!/usr/bin/python
2
3"""
4Copyright 2014 Google Inc.
5
6Use of this source code is governed by a BSD-style license that can be
7found in the LICENSE file.
8
9ColumnHeaderFactory class (see class docstring for details)
10"""
11
12# Keys used within dictionary representation of each column header.
13# NOTE: Keep these in sync with static/constants.js
14KEY__EXTRACOLUMNHEADERS__HEADER_TEXT = 'headerText'
15KEY__EXTRACOLUMNHEADERS__HEADER_URL = 'headerUrl'
16KEY__EXTRACOLUMNHEADERS__IS_FILTERABLE = 'isFilterable'
17KEY__EXTRACOLUMNHEADERS__IS_SORTABLE = 'isSortable'
18KEY__EXTRACOLUMNHEADERS__VALUES_AND_COUNTS = 'valuesAndCounts'
19
20
21class ColumnHeaderFactory(object):
22  """Factory which assembles the header for a single column of data."""
23
24  def __init__(self, header_text, header_url=None,
25               is_filterable=True, is_sortable=True,
26               include_values_and_counts=True):
27    """
28    Args:
29      header_text: string; text the client should display within column header.
30      header_url: string; target URL if user clicks on column header.
31          If None, nothing to click on.
32      is_filterable: boolean; whether client should allow filtering on this
33          column.
34      is_sortable: boolean; whether client should allow sorting on this column.
35      include_values_and_counts: boolean; whether the set of values found
36          within this column, and their counts, should be available for the
37          client to display.
38    """
39    self._header_text = header_text
40    self._header_url = header_url
41    self._is_filterable = is_filterable
42    self._is_sortable = is_sortable
43    self._include_values_and_counts = include_values_and_counts
44
45  def create_as_dict(self, values_and_counts_dict=None):
46    """Creates the header for this column, in dictionary form.
47
48    Creates the header for this column in dictionary form, as needed when
49    constructing the JSON representation.  Uses the KEY__EXTRACOLUMNHEADERS__*
50    constants as keys.
51
52    Args:
53      values_and_counts_dict: dictionary mapping each possible column value
54          to its count (how many entries in the column have this value), or
55          None if this information is not available.
56    """
57    asdict = {
58        KEY__EXTRACOLUMNHEADERS__HEADER_TEXT: self._header_text,
59        KEY__EXTRACOLUMNHEADERS__IS_FILTERABLE: self._is_filterable,
60        KEY__EXTRACOLUMNHEADERS__IS_SORTABLE: self._is_sortable,
61    }
62    if self._header_url:
63      asdict[KEY__EXTRACOLUMNHEADERS__HEADER_URL] = self._header_url
64    if self._include_values_and_counts and values_and_counts_dict:
65      asdict[KEY__EXTRACOLUMNHEADERS__VALUES_AND_COUNTS] = sorted(
66          values_and_counts_dict.items())
67    return asdict
68