Hi,
Language recognition engines will give us a set of tokens, usually in some
sort of tree but the result can be thought of nested collections, for
example:
The following string "g.V().values('name')" could be parsed into something
like [["g"], ["V"], ["values", "name"]].
Then, we would have to create some sort of "evaluator", that translates
these string tokens into a traversal, similar to bytecode parsing and
execution. This evaluator can use static evaluation of the tokens (like, do
the tokens evaluate into something meaningful?), can be optimized with
caching techniques (like preparing traversals) and more importantly, will
only execute class methods that are whitelisted, i.e., users can't use it
to execute arbitrary groovy code.
Best,
Jorge
On Tue, Apr 23, 2019 at 12:36 PM Marko Rodriguez <[email protected]>
wrote:
> Hi Jorge,
>
> > Instead of supporting a ScriptEngine or enable providers to implement
> one,
> > TP4 could be a good opportunity to ditch script engines while continue
> > supporting gremlin-groovy string literals using language recognition
> > engines like ANTLR.
>
> Huh…….. Can you explain how you think of using ANTLR vs
> ScriptEngine.submit(String)
>
> > Language recognition and parsing engines have several benefits over the
> > current approach, most notably that it's safe to parse text using
> language
> > recognition as it results in string tokens, opposed to let users run code
> > in a sandboxed vm.
>
> How would the ANTLR-parsed text ultimately be executed?
>
> Thanks,
> Marko.
>
> http://rredux.com <http://rredux.com/>
>
>
>
