Error tolerant script loading

[davidsminor]

Hello,

Using Gaffer in production, we found pretty quickly that you need to be able to load scripts with dodgy nodes in them, without the load process terminating prematurely. In my software, I've been getting round this by manually executing the scripts line by line. This has worked so far, but I've just noticed a situation where the values in path filter "paths" plugs get saved out on separate lines. This is breaking my code, as the lines no longer make sense in isolation. I imagine it's a matter of weeks before people start complaining about this in production, (I wouldn't be surprised if it's caused problems already). I could probably work around it on my side, but it'd be a workaround on top of a workaround, and it seems like high time we fixed this in Gaffer anyway, so here's a ticket.

[davidsminor]

actually, it looks like my code was failing because some of the string plug values had "\n" in them (which was my fault and shouldn't typically happen). Still, something to look out for...

[johnhaddon]

The ast munging discussed here sounds like it might be a relevant approach :

http://stackoverflow.com/questions/9670931/sandboxing-running-python-code-line-by-line

[ldmoser]

We bumped priority on this as it's already affecting us and will certainly annoy test users.