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8.16 BPEL
A BPEL enactment environment is where application logic in the form of
standard BPEL descriptions is i nally executed, which takes account of pro-
cess deployment, monitoring, and other aspects related to process execu-
tion. We focus on the discussions of these aspects in this section.
ActiveBPEL was one of the i rst BPEL implementations found to be appro-
priate for proper academic research. The software is freely distributed by
Active Endpoints under a Lesser GPL license. It deploys Apache Tomcat as a
Web application, while commercial products that run on mainstream appli-
cation servers with enhanced performance and integration of enterprise
solutions are developed around the very same codebase. Comprehensive
documentation and community supports are available for open-source
users, while ActiveEndpoint also provides training, consultancy, certii ca-
tion, and other professional services. Because of the early availability as a
full-function BPEL enactment engine, ActiveBPEL had been widely adopted
and evaluated, whose quality-assured software development and extensive
user supports have been found to be difi cult for general academic bodies to
catch up with.
Process Enactment and Active
8.17
A BPEL process is given a Web service front end at deployment time with
extra binding and service information appended to the initial process WSDL
description created in design time, which are important to regulate service
messaging and identify service location. No differences are exhibited by
any process after successful deployment from the standpoint of standard
Web services to serve process requests. The BPEL processor at the core of an
enactment engine understands and performs the mapping between the
process description and the equivalent programming statements and proce-
dure calls that can be executed in the server container. WSDL and XSD dei ni-
tions need to be parsed beforehand to construct data models required by
both predeployment validation and process execution. Additionally, process
deployment is likely to require more than a single process document besides
WSDL and XSD descriptors. Extra engine coni gurations and deployment-
time information, like the locations of partner services, may be needed for an
Deployment
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