RE: [Xpipe-developers] Hi...

[David S. <ds...@st...>]

> An XML-RPC invoking XComponent is high on the list. I'll see if I can get
> to is soon.
>
> It is a good test of the XComponent model and a very useful XComponent
> to boot.
Once there is some sort of an executive it seems to me that it would be
interesting to package the XComponent modules that index and document
XCcomponents as XComponents themselves.

On another note, I have some components that I have used on other pipeline
projects that I would be happy to package as XComponents.  The first would
likely be one that can perform arbitrary queries against arbitrary JDBC
sources.

I'm not sure that I fully understand your vision for who XPipes will be
combined.  So before I assume that the philosophy is similar to ones I've
worked with in the past, let me explain the component, then perhaps you can
give me some guidance as to how it might work with the XPipe system.  The
following Javadoc excerpt explains the filter.

JDBCQueryFilter is a SAX pipeline filter that takes occurrences of
<SQLQuery> ... </SQLQuery> in XML documents and executes query defined by
these elements. The <SQLQuery> structure is replaced by a &<QueryResults>>
structure that contains the results of the query. The SQLQuery element
requires that four elements be specified.

Driver - The class name of the JDBC driver to use.
DatabaseURL - A URL specifying where to find the database.
Login - The login used to authenticate with the database.
Password - The password associated with the given Login. The results are
replaced with a structure that looks like <QueryResults> <Row> <Cell
column="name of column" value="value of column"/> <Cell column="name of
column" value="value of column"/> ... </Row> <Row> <Cell column="name of
column" value="value of column"/> <Cell column="name of column" value="value
of column"/> ... </Row> ... </QueryResults> Anything not contained in the
<QueryFilter> structure is passed through the filter untouched.

It's fairly trivial to change this from an SAX filter to an XCOmponent.  But
does it fit the XPipe paradigm.  Would it be more useful if the query was
supplied as a parameter.  If so, how would one specify where to place it in
the source document.

David