According to the ALF 2005 Eclipse Word presentation, “Apache
Agila (aka Twister) is the current primary choice for the orchestration engine”.
I installed and tried both Agila and ActiveBPEL. I would
not want to use Agila in the POC. I can’t justify Agila as being a
primary choice for the POC. My comparison of the two is given
below.
Can anyone give a few good reasons for using Agila over
ActiveBPEL?
I tried both the Apache Agila BPEL engine as well as that of
ActiveBPEL. I found ActiveBPEL to be much easier to install and target
for deploy, with a far larger community.
Installation Requirements:
=======================
Agila
* Servlet containter (e.g., Tomcat 5)
* Relational Database (e.g, MySQL, Oracle; HSQL-DB provided)
* XML Database (Apache XIndice provided)
* Subversion Client
* Apache Maven
* XDoclet 1.2.x (has plugin required for Maven)
* Apache Ant
ActiveBpel
* Servlet containter (e.g., Tomcat 5)
Deploy Procedure
========================
Agila
* Done through web interface (not fully tested to verify). During
the course of my testing with Agilia’s error-riddled samples, I managed
to corrupt the Agila engine’s relational database and could not verify its
web deploy page.
ActiveBPEL
* Done by copying ActiveBPEL custmom jar. Requires
tedious creation of ActiveBPEL “process deployment description”
file.
A forum user has contributed java code to automatically
generate this pdd file given the BPEL and WSDL inputs. (not tested to verify)
Community
==========
Agila
Sparsely contributed to gzipped mail archive (e.g., 2 posts
for all of September 2005).
ActiveBPEL
Five forums actively monitored by admins who provide
explanations, fix suggestions. Over 2,500 posts from about 400 registered
users.
Docs/Samples
============
Agila
A wiki site w/three web page guides for Install, Users,
Development. Three error-riddled samples, missing message definitions,
etc.
ActiveBPEL
Several guides for installation, usage, deployment,
architecture. Six complete samples including client source code and ant
build, deploy, and test scripts. Five of the samples verified to work
with one not building (custom_xpath_function) due to using old ActiveBPEL
version API.
Odds & Ends
============
I’m not sure how they compare against
administrative/event APIs available through web services or event/exception
handling. I do know ActiveBPEL supports the former and is fully
implements BPEL4WS1.1.