tko/query_lib.py

   1 """
   2 This library provides a bunch of miscellaneous parameter parsing,
   3 sql generating and list cleanup library functions that are used
   4 by both the reporting cli and web interface.
   5 """
   6
   7 import sys, os, re
   8
   9 tko = os.path.dirname(__file__)
  10 sys.path.insert(0, tko)
  11
  12 import display, frontend, db
  13
  14 db = db.db()
  15
  16 def dprint(str):
  17     pass
  18     #print "! %s<br>" % str
  19
  20 def parse_scrub_and_gen_condition(condition, valid_field_dict):
  21     me = parse_scrub_and_gen_condition   # shorten the name
  22     compare_ops = {'=':'=', '<>':'<>', '==':'=', '!=':'<>', '>':'>',
  23                    '<':'<', '>=':'>=', '<=':'<=', '~':'LIKE', '#':'REGEXP'}
  24
  25     # strip white space
  26     condition = condition.strip()
  27
  28     # ()'s
  29     #match = re.match(r'^[(](.+)[)]$', condition)
  30     #if match:
  31     #       dprint("Matched () on %s" % condition)
  32     #       depth = 0
  33     #       for c in match.group(1):
  34     #               if c == '(':    depth += 1
  35     #               if c == ')':    depth -= 1
  36     #               if depth < 0:   break
  37     #       dprint("Depth is %d" % depth)
  38     #       if depth == 0:
  39     #               dprint("Match...stripping ()'s")
  40     #               return me(match.group(1), valid_field_dict)
  41
  42     # OR
  43     match = re.match(r'^(.+)[|](.+)$', condition)
  44     if match:
  45         dprint("Matched | on %s" % condition)
  46         (a_sql, a_values) = me(match.group(1), valid_field_dict)
  47         (b_sql, b_values) = me(match.group(2), valid_field_dict)
  48         return (" (%s) OR (%s) " % (a_sql, b_sql),
  49                 a_values + b_values)
  50
  51     # AND
  52     match = re.match(r'^(.+)[&](.+)$', condition)
  53     if match:
  54         dprint("Matched & on %s" % condition)
  55         (a_sql, a_values) = me(match.group(1), valid_field_dict)
  56         (b_sql, b_values) = me(match.group(2), valid_field_dict)
  57         return (" (%s) AND (%s) " % (a_sql, b_sql),
  58                 a_values + b_values)
  59
  60     # NOT
  61     #match = re.match(r'^[!](.+)$', condition)
  62     #if match:
  63     #       dprint("Matched ! on %s" % condition)
  64     #       (sql, values) = me(match.group(1), valid_field_dict)
  65     #       return (" NOT (%s) " % (sql,), values)
  66
  67     # '<field> <op> <value>' where value can be quoted
  68     # double quotes are escaped....i.e.  '''' is the same as "'"
  69     regex = r'^(%s)[ \t]*(%s)[ \t]*' + \
  70             r'(\'((\'\'|[^\'])*)\'|"((""|[^"])*)"|([^\'"].*))$'
  71     regex = regex % ('|'.join(valid_field_dict.keys()),
  72                      '|'.join(compare_ops.keys()))
  73     match = re.match(regex, condition)
  74     if match:
  75         field = valid_field_dict[match.group(1)]
  76         op = compare_ops[match.group(2)]
  77         if match.group(5):
  78             val = match.group(4).replace("''", "'")
  79         elif match.group(7):
  80             val = match.group(6).replace('""', '"')
  81         elif match.group(8):
  82             val = match.group(8)
  83         else:
  84             raise "Internal error"
  85         return ("%s %s %%s" % (field, op), [val])
  86
  87
  88     raise "Could not parse '%s' (%s)" % (condition, regex)