[EMAIL PROTECTED] wrote:
Here's an apparent catch-22 about installing PEAR files that I don't quite
understand.
How is installation supposed to work when there's a configuration parameter
or external resource in the component descriptor that is both required and
doesn't have a default value?
For example, I have one external resource that is the name of a certain file
you want the annotator to use (it's some static reference data). This is
required--the annotator can't operate without it. And there can be no
reasonable default--we can't guess the name of the file the customer will
want to use when we create the component descriptor.
What is suggested here is to include a dummy version of the static
reference data as a resource. Then set the parameter to reference that
resource. Of course, after "install", the user will need to configure
this to their actual data file.
So the user installing the PEAR file really must set it to something before
running the annotator.
So I bound a path that works on my development machine. However, on the
customer's' machine this fails when installer attempts verify the component
by loading the annotator classes and calling initialize():
com.ibm.uima.resource.ResourceInitializationException:
Could not access the resource data at
file:/C:/blah/blah
You want to bind a path that is a resource in the PEAR, and then use the
$macro capabilities to have that path adjusted at install time to take
into account where it was installed.
I tried just leaving the resource unbound, but first the component editor
complains ('There is no resources satisfying the required resource dependency
with key "blah.blah.blah"'), and then during installation I get the same
ResourceInitializationException.
I also tried binding it to a URL that doesn't exist, but the component
editor complains about that too ('Could not access the resource data
at blah'), and then the installer throws ResourceInitializationException
again.
A similar thing happens with configuration parameters that are required
and not defaulted, it just happens later in the installation process,
when you try to run the AE in the CVD, and the call to process() fails when
our software throws an exception about the missing value.
Right - to get this to pass validation, you have to have some defaults.
At least with configuration parameters there's a opportunity in the install
process between pushing "Install" and "Run your AE in the CAS Visual
Debugger" to edit the descriptor file. But there's no such opportunity
with the required external resources, since verification happens immediately
after the files are extracted from the PEAR file.
What is the intended path of sucess here? It doesn't seem possible.
It seems to me that the installation process needs a step between extraction
and verification in which the user can configure the AE by editing the
descriptor (either in a text or XML editor, or in the Eclipse Component
Descriptor editor).
This is a good suggestion for an enhancement.
Absent this enhancement, will the approach outlined abouve work in your
situation?
-Marshall
