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Hi all - I am selecting certain records from a table. Within the <dtml-in> loop, I need to execute a cgi script residing on a second server (which is not hosting zope) for each row of returned data. How?? I can’t use RESPONSE.redirect, that I know of, because it does not return control to the originating zope page it was called from after executing. I’ve installed ZCGI, but that doesn’t seem to facilitate cgi scripts on a different machine. I’ve tried a simple python script which imports urllib and then try’s a urlopen, but that didn’t work either. Has anybody had to solve a similar problem or know where I’m going wrong ?

I like external Python methods for that kind of thing. There are a few things to beware of, though (not specific to external methods). First, the call for each row will have to complete before the next one starts, which will probably be very time consuming. To avoid this, you would use multiple threads in an external method. But even then, if one of the sites does not respond for any reason, its thread will not return (or it may have to wait for a long timeout, like minutes in some cases). You will not be able to complete until all threads return, so you can still get long delays. To avoid this, it would be possible to write code to test a site first to see if it responds, (you may have to get a special socket library that can be interrupted if it is hanging - I know that at least one such library exists for Python) but of course it would be more complicated.

To sum up, you can make this work with external methods but you should see if you can come up with some way to avoid the need for going to a site for each row. Can you cache the data, for example?