Conforming to the CCM specification, you should have to provide three kinds of meta files,
since the Corba Component Descriptor
will be generated from CIDL.
-
The Component Assembly Descriptor:
<assembly>.cad
This is the main descriptor you must take care about when setting up
a distributed application. It allows you to point out which packages will be involved,
which Component Servers will be the targets for the homes, and which connections to do at
deployment time.
The actual version of OpenCCM's deployment tool (ccm_deploy
) supports
hostcollocation
and processcollocation
. That
means you can describe your partitioning with these features, using
homeplacement
.
The destination
tag is simply used to mention the
Component Server registered with the Naming Service.
For each homeplacement
, you select packages using a
componentfileref
refering to pre-defined packages.
This is done in the componentfiles
part of the file, using
componentfile
tags that will point to CSD files.
Another important part is the connections
one. For each
connectinterface
or connectevent
you have to operate, you
must simply fill the tags with references to components (with
componentinstantiationref
pointing the IDs defined in
partitioning
), and identifiers to specific connectors:
usesidentifier
, providesidentifier
,
consumesidentifier
, publishesidentifier
.
-
The Software Package Descriptor:
<package>.csd
This descriptor provides every information concerning a particular package:
IDL reference, various implementations for specific languages, OS, compilers...
Again, the OpenCCM's deployment tool does not need/support each of the tags from
the CCM specification. Meta informations such as title, license, author,... are not
used by the deployment tool, but should be filled in order to
share components.
At current stage, the ccm_deploy
tool supports ONE
implementation
tag; that means you should need more than one CSD file
in case of testing various OS, for example.
The important tags are the fileinarchive
and entrypoint
contained in code
. They refer to the JAR file containing
your business code, and to the public static create_home
method of the
implementation.
-
The Property File Descriptor:
<file>.cpf
Setting properties on components is done using this meta descriptor. In CCM
specification, you should be able to refer a properties file anywhere in the
Assembly Descriptor
, at home level or component level, or in the
Software Package Descriptor
, at package level or
implementation level.
The OpenCCM's deployment tool remains quite limited on properties. First, it
only looks for a propertyfile
reference into the Component
Assembly Descriptor
, at component level. Second, it only accepts
simple
tags describing string
values.