m_librarian/search.py

   1
   2 from sqlobject.sqlbuilder import AND, func
   3 from .db import Author, Book, Extension, Genre, Language
   4
   5 __all__ = [
   6     'mk_search_conditions',
   7     'search_authors', 'search_books', 'search_extensions',
   8     'search_genres', 'search_languages',
   9 ]
  10
  11
  12 def _mk_search_conditions_with_operator(table, case_sensitive, comparison_op,
  13                                         values, expressions):
  14     if expressions is None:
  15         expressions = []
  16     _expressions = []
  17     for column, value in values.items():
  18         if column == 'id':
  19             _expressions.append(table.q.id == value)
  20             break
  21     if case_sensitive:
  22         for column, value in values.items():
  23             if column == 'id':
  24                 continue
  25             _expressions.append(
  26                 getattr(getattr(table.q, column), comparison_op)(value))
  27         for expr, value in expressions:
  28             _expressions.append(
  29                 getattr(expr, comparison_op)(value))
  30     else:
  31         for column, value in values.items():
  32             if column == 'id':
  33                 continue
  34             _expressions.append(
  35                 getattr(func.lower(
  36                     getattr(table.q, column)),
  37                     comparison_op)(value.lower()))
  38         for expr, value in expressions:
  39             _expressions.append(
  40                 getattr(func.lower(expr), comparison_op)(value.lower()))
  41     return _expressions
  42
  43
  44 _comparison_operators = {
  45     'start': 'startswith',
  46     'substring': 'contains',
  47     'full': '__eq__',
  48 }
  49
  50
  51 def mk_search_conditions(table, search_type, case_sensitive, values,
  52                          expressions=None, join_expressions=None):
  53     if join_expressions is None:
  54         join_expressions = []
  55     return _mk_search_conditions_with_operator(
  56         table, case_sensitive, _comparison_operators[search_type],
  57         values, expressions) + join_expressions
  58
  59
  60 def _search(table, search_type, case_sensitive, values,
  61             expressions=None, join_expressions=None, orderBy=None):
  62     conditions = mk_search_conditions(
  63         table, search_type, case_sensitive, values, expressions=expressions,
  64         join_expressions=join_expressions)
  65     return table.select(AND(*conditions), orderBy=orderBy)
  66
  67
  68 def search_authors(search_type, case_sensitive, values,
  69                    expressions=None, orderBy=None):
  70     return _search(Author, search_type, case_sensitive, values,
  71                    expressions=expressions, orderBy=orderBy)
  72
  73
  74 def search_books(search_type, case_sensitive, values, join_expressions=None,
  75                  orderBy=None):
  76     return _search(Book, search_type, case_sensitive, values,
  77                    join_expressions=join_expressions, orderBy=orderBy)
  78
  79
  80 def search_extensions(search_type, case_sensitive, values, orderBy=None):
  81     return _search(Extension, search_type, case_sensitive, values,
  82                    orderBy=orderBy)
  83
  84
  85 def search_genres(search_type, case_sensitive, values, orderBy=None):
  86     return _search(Genre, search_type, case_sensitive, values,
  87                    orderBy=orderBy)
  88
  89
  90 def search_languages(search_type, case_sensitive, values, orderBy=None):
  91     return _search(Language, search_type, case_sensitive, values,
  92                    orderBy=orderBy)