Re: Feasibility of system() plugin?

["Andreas J. Guelzow" <aguelzow taliesin ca>]

Leigh Smith wrote:

> I've just got up to speed on gnumeric on MacOS X after converting some 
> spreadsheets from sc. I'm considering writing a gnumeric plug-in to suit 
> my needs, but wanted to check that the functionality isn't already in 
> gnumeric and I've somehow missed it.
>
> I'd like to retrieve market data and have the share prices appear in 
> cells that can then be used for calculations. Recalculating the sheet 
> would cause new values to be fetched.
>
> The easiest way I can see that would have some value to everyone else 
> would be to implement a function SYSTEM() that would take a string of 
> the command to be executed and return a numeric value. Therefore 
> =SYSTEM("get_shares ORCL")
> would evaluate to the current share price. get_shares is just a shell 
> script I have that can grab the values using curl and print the share 
> price on stdout and do some caching of data fetches.
>
> If I'm not already reproducing a function that exists (I don't want to 
> just import a CSV file each time the data changes), I'm happy to write a 
> plugin,
>  (the plugin API looks pretty straightforward) and I'll contribute it back.
>  Obviously I could do this via the Python plugin, but it seems a bit of 
> overkill to use python just to execute an external command. Strictly 
> speaking I could define a number of functions that return different 
> formats of data, but the one that scans the output for the first float 
> seems the most useful initially.
>
> Thoughts?


I would be greatly concerned about security issues. This function would 
likely be executed upo loading of a possible untrusted worksheet...

Andreas




--
Prof. Dr. Andreas J. Guelzow
http://www.math.concordia.ab.ca/aguelzow