[rules-users] This (ordered) record validation approach is working

[ronalbury]

I didn't get any feedback when I posted earlier today, so I went ahead and
implemented what I thought would work ... and I figured I should share it
here since it seems to be working pretty well.

I created a Rule Flow as follows:
   A Rule-Flow-Group that validates the arrays.  Unfortunately I sometimes
get multiple related arrays of records instead of a single array of records. 
I confirm that records with mandatory values have arrays with at least one
element, and confirm that the related arrays are of equal length.  Errors
are logged.

   A subsequent Rule-Flow-Group that manages inserts.  The data actually
comes to me as one data structure comprised of sub-records of various types,
and I have DRL files for each record type.  Some of the sub-records are
optional, and since subsequent rules would erroneously flag empty
sub-records as errors I have rules here which only allow optional records
containing values to be inserted into the system.  I am currently using
for-loops in the THEN section of some rules to deal with the array problem
and would like to know if there is a better way.  No errors are generated
here.

   A subsequent Rule-Flow-Group that validates data.  The data is all sent
to me as Strings, even though many of the values are numbers, dates, etc. 
This Rule-Flow group tests the various fields using regular expressions, and
if a regular expression fails then the record is flagged as having an error. 
Optional fields are dealt with by the regular expression allowing a blank. 
Errors are logged.

   A Diverging Gateway that splits the data into two ... records without
validation errors are allowed to progress to the value-checking Rule-Flow
group ... those with errors have nothing more done to them.  I realize that
I could, for instance, let records with bogus numbers thru as long as my
string-to-integer routine is robust, however I don't want to flag the same
record multiple times (once by reg-ex and then again by the next
Rule-Flow-Group).

   A subsequent Rule-Flow-Group that checks the values and ranges of the
numbers, dates, etc, and does other types of validation (e.g. if fieldA has
a value greater than 20 then fieldB must be set to "XYZ").  Errors are
logged.


This Rule-Flow approach currently seems to be solving all of my problems,
and it allows me to keep the rules simple and well structured such that most
of them are reusable in other parts of our system.

I'm interested in getting feedback on this approach ... it seems to be
working pretty well for me.  It allows me to deal with ordering issues and
many of the if/else issues, while keeping the rules simple enough for our
non-technical analysts to review without needing a developer to sit next to
them.

I realize this is a pretty mundane application for a powerful rules system,
but it seems like a good fit nonetheless.

Thanks
   Ron

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