Revision history for Perl extension Helios.

2.31_0172  Sun Jan 08 23:00:00 2012
	-2.40 RELEASE CANDIDATE 2
	-shenanigan prevention
	-Helios::Service->work() returns 0 to helios.pl launch_worker() now 
	 (prevents helios.pl from carping about an undefined return code)
	-sql/helios_schema.sql is more complete; creates database and (if 
	 uncommented) user
	-Bundle::Helios added (still experimental)
	-Updated INSTALL and added INSTALL.ubuntu & INSTALL.redhat
	-Updated Stub::StubService for clarity
2.31_0141  Wed Jan 04 23:00:00 2012
	-2.40 RELEASE CANDIDATE 1
	-Fixed MaxRetries() and RetryInterval()
	-Added INSTALL.ubuntu
	-Removed sql/helios_schema_20upgrade.sql (obsolete)
2.31_0111  Mon Jan 02 23:30:00 2012
	-HeliosX::Logger::Internal: re-added support for 
	 log_priority_threshold config param
2.30_5272  Sun Jan 01 23:30:00 2012
	-Renamed runMetajob() to metarun()
	-Renamed DOWNSHIFT_ON_FAILED_JOB to DOWNSHIFT_ON_NONZERO_RUN to 
	 make it clearer what it does.
	-Rewrote Helios::TestService to be more clear and up-to-date.
	-Updated copyright notices (Happy New Year!)
	-Helios::Job:  changed failed() and failedNoRetry() to limit the 
	 char length of the error recorded to 254 chars.  That's one less 
	 than the default size of the db field in the ERROR table, so it 
	 should prevent long errors like stack traces from unexpectedly 
	 blowing up worker processes and potentially losing jobs
	-Helios::Service->work():  calls to run() and metarun() are now 
	 wrapped in an eval {} block to catch uncaught exceptions.  If the
	 run() or metarun() method of a service dies while processing a 
	 job, the uncaught exception will be caught & logged, the job in 
	 question will be failed, and the worker process will be exited.  
	 This will prevent worker processes from unexpectedly blowing up 
	 and losing jobs.
2.30_5271  Sun Jan 01 11:44:00 2012
	-Changed Helios::Service->work() to ignore the value returned by a
	 service's run() or runMetajob() method by default.  Previous 
	 Helios versions would understand a nonzero return from run() to 
	 mean a failed job, and would force the worker process to end even
	 though the service was in OVERDRIVE mode.  This was considered a 
	 safety measure as the reason for the job failure was unknown.  
	 However, this feature was underdocumented and confusing and has 
	 been removed.  
	 
	 The new default behavior doesn't pay attention to the value returned
	 from run() or runMetajob().  You should mark your job as completed or 
	 failed in run() or runMetajob() and not worry about returning anything.
	 This new behavior also has the advantage of working with all of the 
	 popular modes of Perl exception handling (using Perl's eval {} will return
	 1 if successful, while Try::Tiny and Error's try {} will not).
	 	 
	 Anyone requiring the old behavior can use the new DOWNSHIFT_ON_FAILED_JOB 
	 parameter to enable it.
2.30_5232  Wed Dec 28 20:20:00 2011
	-Added Helios::Service->runMetajob() to update and modularize 
	 metajob handling code.
	-Cleaned up some unnecessary warnings from work() and logMsg()
	-Removed vestigial dependency on XML::Parser in Helios::Service
	 (forgot that was in there)
2.30_5072  Wed Dec 20 21:33:00 2011
	-Same as 5071, but with including BaseError and fixed MANIFEST 
	 (oops, sorry!)
2.30_5071  Sun Dec 18 02:30:00 2011
	-Added Helios::Error::BaseError and modified all Helios::Error::
	 exception classes to subclass it instead of Error::Simple 
	 directly.  This creates an actual exception class hierarchy, 
	 and makes it easy to determine whether a caught exception is a 
	 Helios error or another kind of error.  (It might also allow 
	 an eventual move from Error to another exception handling 
	 system.)
2.30_5041  Thu Dec 15 23:40:00 2011
	-Completely rewrote submitJob.pl to allow requester to send job 
	 arg XML in an HTTP POST; the form encoding is no longer 
	 necessary (though is still supported to ensure compatibility)
	 See submitJob.pl for updated job XML syntax
	 New submitJob.pl also eliminates dependency on HELIOS_CLASS_MAP 
	 to determine the proper class for a particular job type (though 
	 HELIOS_CLASS_MAP is still supported)
	-Removed vestigial dependency on XML::Parser in Helios::Job &
	 removed mention of it in Makefile.PL
	-Corrected Makefile.PL to remove mention of XML::SAX, 
	 XML::Namespace as dependencies (Helios's only direct XML::*
	 dependency is XML::Simple)
	-Corrected Makefile.PL with older versions of DBI and XML::Simple.
	 These versions were packaged as RPMs with CentOS 5.7.  This 
	 change helps installation on RPM-based Linux OSes, and Helios is 
	 compatible with these versions.
2.30_4931  Wed Dec 07 00:52:00 2011
	-Switch to "Linux-style" versioning: 
	 odd minor version == development version
	 even minor version == stable version
	 second minor number == patch level
	 (we're still also using Perl-style _ for devel versions too)
	-Merged in HeliosX::ExtLoggerService functionality 
	 (long overdue but not tested yet!)
	-Removed Helios::Service->parseArgXML() (deprecated since 2.00)
	-Removed Helios::Worker (deprecated since 2.00)
2.23  Fri Sep 10 12:22:00 2010
	-Helios::Job: fixed bug where getArgXML() returned undef if job
	 object was vivified from job queue
2.22  Thu May 21 11:30:00 2009
	-Helios::Service: fixed a bug in getFuncidFromDb() that caused 
	 services to fail to load properly if there was no entry for them 
	 in FUNCMAP table.
	-helios.pl: Several revisions to make it a more robust daemon. Now
	 honors TERM signal; 'kill <pid>' from a shell will attempt to 
	 safely shut down workers and daemon process w/o using Panoptes
	-Documentation updates
2.21  Thu May 14 17:00:00 2009
	-added set/getJob() accessors to facilitate access to current 
	 Helios::Job object from methods other than run()
2.20  Tue Apr 28 18:00:00 2009
    -various tweaks for cross-platform compatibility
    -documentation additions/corrections
    -added Helios::LogEntry::Levels to remove dependencies on 
     Sys::Syslog
    -helios.pl: Cleaned up messages to console after daemonize
	-helios.pl + Helios::Service: added support for WORKER_MAX_TTL 
	 config param
    -Helios::Service: added JobClass() allow extensible Helios::Job 
     classes
    -Helios::Service: added MaxRetries() and RetryInterval() to replace
     TheSchwartz's max_retries() and retry_interval() (this is not an 
     abitrary change; it's to allow for extensions at the Helios layer 
     in the future)
    -Helios::Service: added default run() method for class completeness
     (it throws a Helios::Error::FatalNoRetry error because you forgot 
     to implement a run() method)
    -Helios::Service: removed logging to syslogd to eliminate 
     Sys::Syslog dependency (see HeliosX::ExtLoggerService)
    -Helios::Service: added set/getFuncid(), getFuncidFromDb() and 
     changed jobWaiting() to use them.  This eliminates an unnecessary 
     database query previously done every time jobsWaiting() was called
    -Helios::Service: added support for log_priority_threshold config 
     param
    -Helios::Job: added getFailures() to access the number of times a 
     job has previously failed
2.00  Fri Aug 01 02:00:00 2008
	-First public production release (same as 1.90_26 w/more documentation)
1.90_26 Thu Jun 26 11:30:00 2008
	-Helios 2.0 RC1
	-NEW Helios 2.0 API
	 Helios::Service
	 Helios::Job
	 Helios::MetajobBurstService
	 Helios::ConfigParam
	 Helios::JobHistory
	 Helios::LogEntry
	 Helios::TestService
	-helios.pl: added PID check to prevent 2 instances of a service 
	 running on the same server
	-helios.pl: added --clear-halt option to clear Worker Admin HALTs 
	 at the cmd line
	-helios.sql: new helios_worker_registry_tb.start_time field for 
	 uptime stats
	-submitJob.pl, helios_job_submit.pl, helios_job_clean.pl use new 
	 2.0 API
	-eg/Stub/StubService.pm for example of new 2.0 API service class
	-new tests to test both 1.x and 2.x API	
1.19_07 Thu May 29 14:00:00 2008
	-added Helios.pm (for version checking & documentation)
	-added Helios::Job (for eventual refactoring)
	-added Helios::Test (for system testing)
1.19_06 Wed May 28 12:00:00 2008
	-added LICENSE file that was left out
	-add helios_log_clean.pl utility to clean log, job history
	-added eg/Stub/StubWorker.pm as a worker class stub example
1.19  Mon May 19 12:00:00 2008
	-First public release