search.py

    1 #!/usr/bin/python2
    2 
    3 #######################################
    4 #
    5 # This script is used to search DB and generate page with regults
    6 #
    7 # Version: 1.5
    8 #
    9 #######################################
   10 
   11 #import all functions from lib.py
   12 
   13 from lib import *
   14 
   15 form = cgi.FieldStorage()
   16 
   17 try:
   18     keyword = form['keyword'].value
   19 except:
   20     keyword = ''
   21 
   22 #function to search column title of table books
   23 
   24 def do_search(keyword):
   25 
   26     sql = "SELECT id FROM books WHERE MATCH (title) AGAINST ('%s' IN BOOLEAN MODE)" % keyword.lower()
   27 
   28 #### BUG #1
   29 #### Expected: programmer should've used function select() to select all matching rows
   30 #### Actual: function select_one() was used instead, so only first matching record will be returned
   31 #### Note 1:
   32 ####    see description for both functions in code of lib.py
   33 #### Note 2:
   34 ####    As an example: in table 'books' we have two records containing keyword 'adventures':
   35 ####    "the adventures of tom sawyer" (id=3) and 'the adventures of huckleberry finn' (id=10)
   36 ####    So, when user enters 'adventures', only record with id=3 will be returned.
   37 ####    Why? Because: 1. select_one() gets first record it sees. 2. that first record will be record with id=3 (3<10)
   38 
   39     tmp_list = select_one(sql)
   40 
   41     #if nothing is returned by search
   42 
   43     if len(tmp_list) == 0:
   44 
   45         return ''
   46 
   47     else:
   48 
   49 #go over returned list and generate html
   50 
   51 #### Note:
   52 ####    the rest of the code for this function was written as if select() was used and, hence, several records can be returned
   53 
   54         table="<table>"
   55 
   56         for item in tmp_list:
   57 
   58             table = table + show_book(item)
   59 
   60 
   61         table=table + "</table>"
   62 
   63     return table
   64 
   65 
   66 ############Main logic
   67 
   68 #if no keyword is provided
   69 
   70 if keyword == '':
   71 
   72     body_html = ''
   73     message = "Oops, error. No keyword is provided"
   74 
   75 #it's unfortunate but MySQL search engine has default limitation of seaching for words with 4 or more chars only
   76 #we cannot change this now, so we created a message for our users
   77 
   78 elif len(keyword) <= 3:
   79 
   80     body_html = ''
   81     message = "Please, note that current MySQL settings don't allow  searches for words containing less than 4 chars"
   82 
   83 else:
   84 
   85     body_html = do_search(keyword)
   86 
   87     if body_html == '':
   88 
   89         message = "Nothing is found :("
   90 
   91     else:
   92 
   93         message = ''
   94 
   95 #execute code below if this script is run as standalone script
   96 #don't execute code below if we import functions from this script
   97 
   98 if __name__ == "__main__":
   99 
  100     ############Determine if user is logged in
  101 
  102     is_logged_in = is_logged_in()
  103 
  104     #############generate and print html
  105 
  106     print 'Content-Type: text/html\n\n'
  107 
  108     caption = 'Search'
  109 
  110     html=get_html(is_logged_in,body_html,caption,message)
  111 
  112     print html
  113