Some answers inline below: On Mon, Mar 22, 2021 at 5:00 PM Joshua Shinavier <j...@fortytwo.net> wrote:
> I am not yet entirely sure what it means either, but I am thinking that it > would be nice to be able to > a) validate Gremlin expressions written in languages other than Groovy or > Java, and > Yes - that would be a nice practical feature. > b) parse Gremlin expressions in Gremlin language variants, producing > JVM-based traversals, or even > I like this idea too. It would be nice if Gremlin strings didn't have to be constrained to a Groovy syntax when you're familiar with Python. > c) parse Gremlin expressions in Gremlin language variants, producing native > traversals in the host language > These options range from easy (a) to hard (c). > This idea has long been on my mind in various ways. I'm not sure how we'd ever reasonably try to do that, but if I were to be pressured for a subject/theme for TP4 I think this would be it. > Another way to look at this is: let's use Stephen's grammar as a template > for a more generic grammar which is more flexible w.r.t. the input > language. > > Josh > > > > On Mon, Mar 22, 2021 at 11:37 AM pieter gmail <pieter.mar...@gmail.com> > wrote: > > > Hi, > > > > Exciting as this is I am not quite sure what it means. > > > > Naively perhaps it the idea, > > Arbitary gremlin string -> antlr parser -> some AST walker -> gremlin > > byte code -> java in memory steps ... -> voila > > > > Is the grammar going to be the primary and only > > interface/specification, or will the native java implementation bypass > > the grammar going straight to the steps instead? > > > > Is this aimed at the gremlin 3 or 4? > > > > Cheers > > Pieter > > > > On Tue, 2021-03-16 at 15:47 -0400, Stephen Mallette wrote: > > > Here is the PR: https://github.com/apache/tinkerpop/pull/1408 > > > > > > On Tue, Mar 16, 2021 at 6:14 AM Stephen Mallette > > > <spmalle...@gmail.com> > > > wrote: > > > > > > > No branch yet, but I think I will be sending the PR today. > > > > > > > > On Mon, Mar 15, 2021 at 9:33 PM Joshua Shinavier > > > > <j...@fortytwo.net> > > > > wrote: > > > > > > > > > Is there a branch we can take a look at before the PR is ready? > > > > > > > > > > Josh > > > > > > > > > > On Fri, Mar 12, 2021 at 5:42 AM Stephen Mallette > > > > > <spmalle...@gmail.com> > > > > > wrote: > > > > > > > > > > > I've been working on forming a pull request for this task. I > > > > > > don't > > > > > think IP > > > > > > Clearance is necessary as I originally did because the > > > > > > contribution is > > > > > > really just an ANTLR4 grammar file with some tests to validate > > > > > > things. > > > > > > Therefore, it's not a big body of independent code as I'd > > > > > > perhaps > > > > > initially > > > > > > envisioned. Compared to gremlint, this addition is pretty > > > > > > simple and > > > > > > straightforward. I've created this issue in JIRA with some > > > > > > additional > > > > > notes > > > > > > on what to expect in this initial body of work: > > > > > > > > > > > > https://issues.apache.org/jira/browse/TINKERPOP-2533 > > > > > > > > > > > > > > > > > > > > > > > > On Mon, Feb 8, 2021 at 10:06 AM Stephen Mallette > > > > > > <spmalle...@gmail.com> > > > > > > wrote: > > > > > > > > > > > > > Just wanted to leave an update on this thread. It was nice to > > > > > > > see some > > > > > > > support for it. I've not had time to focus on the task itself > > > > > > > so sorry > > > > > > > there hasn't been much movement, but I hope to see it on > > > > > > > track soon. I > > > > > > > thought to update the thread after I came across yet another > > > > > > > nice > > > > > usage > > > > > > for > > > > > > > it. I've long wanted to unify our test framework (i.e. > > > > > > > deprecate the > > > > > JVM > > > > > > > process suite in favor of the GLV test suite). I was > > > > > > > experimenting > > > > > with > > > > > > > what that might look like on Friday and hit a circular > > > > > > > dependency > > > > > which > > > > > > > constantly trips things up where gremlin-test wants to depend > > > > > > > on > > > > > > > gremlin-groovy (for ScriptEngine support) but gremlin-groovy > > > > > > > depends > > > > > on > > > > > > > gremlin-test and tinkergraph with <test> scope already. I > > > > > > > think the > > > > > > > introduction of gremlin-script would let gremlin-test build > > > > > > > the > > > > > Traversal > > > > > > > object from a Gremlin string and thus avoid that circular > > > > > relationship. > > > > > > > > > > > > > > On Fri, Jan 8, 2021 at 2:43 AM pieter gmail > > > > > > > <pieter.mar...@gmail.com> > > > > > > > wrote: > > > > > > > > > > > > > > > +1 > > > > > > > > > > > > > > > > I have often thought the language specification should be a > > > > > > > > project > > > > > > > > separate from the implementations, and done in a formal but > > > > > > > > plain > > > > > > > > English format similar to OMG or IETF specifications. > > > > > > > > > > > > > > > > I suspect Sqlg's code base would have been fastly different > > > > > > > > if it had > > > > > > > > evolved from a grammer instead of an api. > > > > > > > > > > > > > > > > Cheers > > > > > > > > Pieter > > > > > > > > > > > > > > > > On Thu, 2020-12-24 at 14:41 -0500, Stephen Mallette wrote: > > > > > > > > > As a project, over the years, we've often been asked the > > > > > > > > > question > > > > > as > > > > > > > > > to why > > > > > > > > > Gremlin doesn't have an ANTLR style grammar. There have > > > > > > > > > been > > > > > varying > > > > > > > > > answers over the years to explain the reasoning but in > > > > > > > > > recent years > > > > > > > > > I've > > > > > > > > > started to see where our dependence on Java for driving > > > > > > > > > Gremlin > > > > > > > > > design has > > > > > > > > > not translated well as we have expanded Gremlin into > > > > > > > > > other > > > > > > > > > programming > > > > > > > > > ecosystems. Using Java has often allowed idioms of that > > > > > > > > > language to > > > > > > > > > leak > > > > > > > > > into Gremlin itself which introduces friction when > > > > > > > > > implemented > > > > > > > > > outside of > > > > > > > > > the JVM. I think that there is some advantage to > > > > > > > > > designing Gremlin > > > > > > > > > more > > > > > > > > > with just graphs/usage in mind and then determining how > > > > > > > > > that design > > > > > > > > > choice > > > > > > > > > looks in each programming language. > > > > > > > > > > > > > > > > > > I think that using an ANTLR grammar to drive that design > > > > > > > > > work for > > > > > > > > > Gremlin > > > > > > > > > makes a lot of sense in this context. We would > > > > > > > > > effectively have > > > > > > > > > something > > > > > > > > > like a gremlin-script which would become the new language > > > > > archetype. > > > > > > > > > New > > > > > > > > > steps, language changes, etc. would be discussed in its > > > > > > > > > context and > > > > > > > > > then > > > > > > > > > implemented in the grammar and later in each programming > > > > > > > > > language > > > > > we > > > > > > > > > support in the style a developer would expect. An > > > > > > > > > interesting > > > > > upside > > > > > > > > > of > > > > > > > > > this approach is that we can implement gremlin-script in > > > > > > > > > the > > > > > > > > > ScriptEngine > > > > > > > > > and replace GremlinGroovyScriptEngine which would help us > > > > > strengthen > > > > > > > > > our > > > > > > > > > security story in Gremlin Server. Groovy processing would > > > > > > > > > just be a > > > > > > > > > fallback to Gremlin scripts that could not be processed > > > > > > > > > by the AST. > > > > > > > > > In fact > > > > > > > > > users who didn't need Groovy could simply not install it > > > > > > > > > at all and > > > > > > > > > thus > > > > > > > > > boast a much more secure system. > > > > > > > > > > > > > > > > > > I think that inclusion of a grammar in our project is an > > > > > > > > > exciting > > > > > new > > > > > > > > > direction for us to take and will help in a variety of > > > > > > > > > areas beyond > > > > > > > > > those > > > > > > > > > I've already related. > > > > > > > > > > > > > > > > > > If we like this direction, Amazon Neptune already > > > > > > > > > maintains such a > > > > > > > > > grammar > > > > > > > > > and would be willing to contribute it to the project to > > > > > > > > > live in > > > > > open > > > > > > > > > source. The contribution would go through the same IP > > > > > > > > > Clearance > > > > > > > > > process > > > > > > > > > gremlint is going through since it was developed outside > > > > > > > > > of > > > > > > > > > TinkerPop. I'd > > > > > > > > > be happy to guide that process through if we draw to > > > > > > > > > consensus > > > > > here. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >
