m_librarian/search.py

   1 from sqlobject.sqlbuilder import AND, OR, func
   2 from .config import get_config
   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, use_filters=False):
  76     if use_filters:
  77         config = get_config()
  78         lang_filter = config.getlist('filters', 'lang')
  79         deleted_filter = config.getint('filters', 'deleted')
  80         if lang_filter:
  81             if join_expressions is None:
  82                 join_expressions = []
  83             lang_conditions = []
  84             for lang in lang_filter:
  85                 lvalues = {'name': lang}
  86                 conditions = mk_search_conditions(
  87                     Language, search_type, case_sensitive, lvalues)
  88                 lang_conditions.append(conditions)
  89             join_expressions.append(Book.j.language)
  90             join_expressions.append(OR(*lang_conditions))
  91     conditions = mk_search_conditions(
  92         Book, search_type, case_sensitive, values,
  93         join_expressions=join_expressions)
  94     if use_filters and not deleted_filter:
  95         conditions.append(Book.q.deleted == False)  # noqa: E712
  96     return Book.select(AND(*conditions), orderBy=orderBy)
  97
  98
  99 def search_extensions(search_type, case_sensitive, values, orderBy=None):
 100     return _search(Extension, search_type, case_sensitive, values,
 101                    orderBy=orderBy)
 102
 103
 104 def search_genres(search_type, case_sensitive, values, orderBy=None):
 105     return _search(Genre, search_type, case_sensitive, values,
 106                    orderBy=orderBy)
 107
 108
 109 def search_languages(search_type, case_sensitive, values, orderBy=None):
 110     return _search(Language, search_type, case_sensitive, values,
 111                    orderBy=orderBy)