few more OSB stories

Recently we finally went-live with a OSB service which on avg, takes 11 secs (it does a lot internally) with 100K+ transactions per day. Two problems we had during this effort


1. StackOverflow Error

There were quite a few Satckoverflow errors, which turned out to be because of a x-path query below

declare function xf:escape-for-regex( $arg as xs:string? )  as xs:string {

      

   replace($arg, '(\.|\[|\]|\\|\||\-|\^|\$|\?|\*|\+|\{|\}|\(|\))','\\$1')

} ;

This function was used to retrieve a certain error message from a complex structured error response, however with some type of error responses, this went into a infinite loop  causing stackoverflow errors.

What was interesting is, weblogic server survived these errors quite gracefully without causing too much trouble with 100+ such errors happening every 10 mnts.

What's even interesting is we didn't see this error in dev environments, so it was a bit inconclusive if the error was due to a certain resource constraint or purely due to the function.

2. Runtime-configuration

One thing I struggled with OSB is to set some global parameters to be set during run time (BPEL has support for runtime global parameters), customization files don't allow any custom properties other than supported by it. Only option was to use some kind of property file and read it through Java call outs. One option we used was to use Xquery files to define these properties. But it was not possible to change these during deployment or runtime. Other option is to keep it in database table and modify through some kind of script or screen.