Generating a report from an ugly log file


#1

Hello,

I have the following problem.

There exists a really ugly debug log file which has mysql query
statements.
Looking through the log makes it hard to understand esp while providing
reports to bosses/mgrs etc. so I have decided to make it more “English”.
I
have over 40 queries, each that can be called in different ways, for
instance:

  1. select foo1, foo2 from foo where foo1=… etc
  2. select foo1 from foo where foo1= etc

The basic parsing would be
/select(.)\s+from\s+(.)(?:\s+where\s+(.*)$)/ #
its a bit more advanced, but its solved and hence not a problem

#captures[1] will be the table name

  1. Each table/view is its own class with a to_english method that does
    the
    translation
  2. An abstract class that parses a line from the log file, extracts the
    table or view (in this case foo) from the match and generates an object
    using eval “#{table.capitalize}.new captures”
  3. The to_english method generates an English representation of the
    object
    based on logic that uses information from the various captures passed
    in.

The idea is to have a list of objects that I iterate over and do a
#to_english

My questions are:

  1. Should I organize this differently and run away from eval?
  2. Since there are over 40 odd classes, is there a better way to require
    them other than:

Dir.glob(“qry*”).each { |r| require r }

Thank you,

Jayanth


#2

On Apr 27, 6:35 am, Srijayanth S. removed_email_address@domain.invalid wrote:

instance:
translation
Do you really need this? It may be overkill if the only thing you will
do in each of these classes is a to_english method. You could perhaps
use a singleton class that contains all the translations.

  1. An abstract class that parses a line from the log file, extracts the
    table or view (in this case foo) from the match and generates an object
    using eval “#{table.capitalize}.new captures”

To avoid eval, use
Kernel.const_get(table.capitalize).send(:to_english)
where to_english is a class method.


#3

Thanks.

Unfortunately, I plan to do more than just to_english. The logs have
information that is also dependent on the ordering of the mysql
statements
themselves, so I want to be able to map queries based on certain
conditions
etc, so no running away from it really, but the Kernel#const_get#send is
a
nice option.

Jayanth