Ha that logo is hilariously awesome! I will add it to the repo later tonight.
I will let you know once I have everything setup regarding the repo. Thanks, On Thursday, April 14, 2016 at 12:10:04 PM UTC-4, Marko A. Rodriguez wrote: > > Hi Mark, > > A logo would be awesome! Thanks. > > > Please see attached. > > I'd love to help with the tutorial. I think it will not only help the > Gremlin community, but the library will get a lot better as a result. Just > let me know where to start and what you'd like to see. > > > We have a way of creating easily creating/publishing tutorials in > TinkerPop3. > > http://tinkerpop.apache.org/docs/3.1.1-incubating/tutorials/ > > I don't know how to do it, but Stephen does. How about you do this: > > 1. You fork Apache TinkerPop tp31/. > 2. You give Stephen and I rights to your forked repository. > 3. Stephen will create the tutorial stub. (this will help me learn when I > see his commit). > - @stephen: call it gremlin-language-variants > 4. You and I then go to town on creating the tutorial. > > Please read over the ticket and comment as appropriate so we jive and are > on the same page going into this: > https://issues.apache.org/jira/browse/TINKERPOP-1232 > > Thank you Mark, > Mark…………….o. > > http://markorodriguez.com > > > > > > > > > > > > On Thursday, April 14, 2016 at 10:47:14 AM UTC-4, Marko A. Rodriguez wrote: > > Hi Mark, > > I think that any host language embedding should use its native idioms > while, at the same time, staying as true as possible to Gremlin-Java (not > Gremlin-Groovy -- though they are nearly identical). I would argue that > Gremlin-Java is the "true representation" of the language. So what do I > mean by native idioms? > > in_V vs inV // if camel case isn't a thing in the native language > $g vs. g // of course if thats how variables are referenced > …huh, can't think of anything else :). But I hope you get the point. > > I notice in Gremlin-Py you do g.v(2) vs g.V(2). Why is that? > > *** Would you be interested in working on a tutorial (with me?) about the > 3 ways to create a Gremlin language variant. Given your expertise in Python > and the existence of Gremlin-Py, I think we can both (1) make a good > tutorial to teach others down the line and (2) spruce up Gremlin-Py's > documentation and appearance (e.g. you need a Gremlin logo! -- Gremlin with > a Snake around his neck? -- want me to make you one?). *** > Please see: https://issues.apache.org/jira/browse/TINKERPOP-1232 > > Thanks Mark, > Marko. > > http://markorodriguez.com > > On Apr 14, 2016, at 8:28 AM, Mark Henderson <emeh...@gmail.com> wrote: > > I think writing "Gremlin/Groovy" in a host language is pretty awesome as > long as it isn't too far off from writing actual Gremlin. I can revive my > PHP project if it would be helpful to the community. A JavaScript version > would probably be one that would get the most attention from developers > today, but JS, even with es6, doesn't have the flexibility (maybe with > Proxies) with its objects where you wouldn't have to write a full-on 1-to-1 > api equivalent of Gremlin (let alone mimicking Groovy). It seems like a > Ruby version would be doable by implementing `method_missing` > > Thanks for adding Gremlinpy to the new site (I need to clean up the code a > bit *shame*) > > On Thursday, April 14, 2016 at 9:34:40 AM UTC-4, Marko A. Rodriguez wrote: > > Hi Mark, > > Exactly. I never saw Gremlin-Py until now and just noticed it on the > Apache TinkerPop homepage. That is good stuff. Moreover, as you say, there > is a distinction between: > > 1. Writing Gremlin in a host language. > 2. Communicating to a GremlinServer-compliant server in a host language. > > The (1) is about query syntax and the (2) is about protocol stuffs. > > Lots of the libraries either confound the two or just do (2) with (1) > simply being a Groovy String (cheesy). > > I would like to see a lot more (1) of the community libraries as I think > this is one of the big selling points of Gremlin -- write in your native > language. > > BTW, I added Gremlin-Py to the description in the "host language > embedding" section here: http://www.planettinkerpop.org/#gremlin (2 > scrolls down). > > Thanks for your thoughts, > Marko. > > http://markorodriguez.com > > On Apr 14, 2016, at 7:06 AM, Mark Henderson <emeh...@gmail.com> wrote: > > I've written "native object to Gremlin" libs in both PHP and Python and it > isn't too bad/not too far from Groovy. The biggest issues were around > indices [..] (when it had that format) and closures "{x -> ...}", but > otherwise both langs allowed for easy query building. > > It basically looked like this in PHP: > > $g= Gremlin(); > $g->V()->has('"name"','mark'); > echo (str)$g; //g.V().has("name",SOME_BOUND_VAR_1) > > Works pretty much the same with the Python lib that I've been building ( > https://github.com/emehrkay/gremlinpy). > > If we wanted to actually execute the query on every step, that wouldn't be > too difficult to implement with Gremlinpy. Gremlinpy is a simple linked > list, it looks at g.V().has('"name"', 'mark') as three token objects with a > shared pool of bound parameters. It creates the string query and parameters > dictionary when you cast the list to a string. The only change needed would > be to bind in a library like Gremlinclient ( > https://github.com/davebshow/gremlinclient), build the query with every > step, and send it to the server. > > res = g.V() # sends request > res2 = g.V().has('"name"', 'mark') # second request > ... > > The remaining difficulty would be deciding what gets bound. Maybe you can > pass in a key val pair for what you want bound > > res = g.V().has('"name"',{'NAME':'mark'}) # g.V().has("name",NAME) > > > > On Tuesday, April 12, 2016 at 10:54:08 PM UTC-4, Dmill wrote: > > Yes a lot of the points you bring up are valid. > > One of the main problems with stringifying everything is that it does not > allow for some of the stuff I mentioned in my PS. That is to name "smart > merges". This query building behavior that makes use of scopes is > unfortunately the standard for frameworks in the industry. > This is mostly due to the SQL heritage and it's declarative nature ; > ordering of "steps" doesn't matter so it allows for easy "after the fact" > client side filtering. It's not uncommon to have a base query that gets > altered by some filtering data. In some cases it's a simple has() that > needs to be injected somewhere, in other cases it's a repeat() that needs > to be completely altered. > Use cases can get a little complicated here but in it's simplest form > imagine having to add/remove entries to/from a match(). Of course that > scenario works well with a toString approach but for other steps, not so > well. Our experience has been that the builder needs to be aware of the > step's signatures to resolve merges. > > So sure this is another problem entirely, in the end users can't really do > this with string queries either. But for widespread adoption it would be > best if the query builder could handle these scenarios. > > Also to bounce off of some of your comments : > > > $id -> "~id" > > $label -> "~label" > > g.V().out("%%x") > > $g->V()->has($id,Number::long(36)) ==> g.V().has("id",36l) > > All of the above are absolutely possible. But it's a lot to keep in mind > for users that are already trying to figure out how Gremlin works. Now they > also need to translate gremlin-groovy into gremlin-php. > One of the advantages of going the hard route and keeping track of all > step signatures instead of a toString approach is that you can > significantly reduce the above cases. The builder can resolve quite a few > of these automatically and when conflicts arise it can do it's best to > resolve it and throw/log a warning telling the user how he could explicit > his query. > > >For your Date example, you would have to have a special "toString()" for > PHP dates to Java dates (or whichever backend ScriptEngine is being used). > > There are no PHP Dates [insert desperate crying emoji here]. PHP sucks > with typing. It's got it's good points but this kind of stuff is not one of > them. Basically PHP Dates come in various forms, from Integer timestamps to > String and only the user really knows what he wants. We can provide this > functionality like you did with long() but it's another thing to keep in > mind. > > One point we haven't gone over have been lambdas. We can't really toString > these. I guess this is where customStep() or script() come in play. > > To wrap it up, a toString query builder is absolutely an option and could > cover a lot of the API. In fact in PHP we could magically make any API > method available, $g->something("~label", "lolo") would stringify to > g.something(label, > "lolo") regardless of whether or not the step exists. But this involves > quite a few language specific alterations and doesn't provide much (if any) > functional benefit. > It would be so much easier for people to just write a gremlin-groovy > string as it's well documented and doesn't need any extra knowledge. > If on the other hand the query builder has features like mentioned in the > PS or earlier in this post, it's well worth the effort. I believe most > people who build their own query builders do so to support some form of > extra feature they wouldn't have by using gremlin-groovy string queries. > But such a query builder enters the realm of non-trivial (although not > unachievable). A first step in helping people make these builders would be > to provide an easily parseable list of signatures for the most desirable > classes. Maybe something along the lines of a yaml file. > > Anyways I'm just thinking out loud at this point. > > > > > > On Tue, Apr 12, 2016 at 9:42 PM, Marko Rodriguez <okram...@gmail.com> > wrote: > > Hi Dylan, > > Your email is excellent. Thank you for breaking things down for me. Here > are some responses. > > *1. Method overloading :* > > abstract class Query { > public function has(PropertyKey $key); //1 > public function has(PropertyKey $key, Object $value); //2 > public function has(Label $label, String $value); //3 > public function has(VertexId $id, Long $value); //4 > public function has(VertexId $id, Int $value); //5 > public function has(VertexId $id, Predicate $p); //6 > } > > The above is illegal in languages like PHP (or javascript?). Instead we're > stuck with : > > abstract class Query { > public function has(Array $args); > } > > We're then left to figure out what is what in the array and sort out how > we need to stringify the output. > > > I was thinking, why would you need to introspect into the array? Just > toString() each element in the array with a comma (,) in between. For > instance: > > * has("age",32) ==> has(["age",32]) ==> has("age",32) // all String array > element need " " wrappers. > * has("age") ==> has(["age"]) ==> has("age") > * has("person","name","marko") ==> has(["person","name","marko"]) ==> > has("person","name","marko") > > Thus, Gremlin-PHP have one has()-method and that method just iterates the > arguments and toString()'s thing accordingly with comma deliminators. > > If the user does $g->V()->has("label", "user") do we add quotes to the > first argument or is it a label/id? What about the second argument, is it a > predicate? etc. This gets complexe very quickly. > > > The universal rule --- if its a String add quotes. If its not, don't. > > $id -> "~id" > $label -> "~label" > > $g->V()->has($label,"user") > > And what if I had $g->V()->has("id", 36) . PHP only supports Int so one > of the two signatures (4 or 5) needs to give as we have a major conflict. > This example is fictional for has() but I've run into this on a couple of > other methods, just can't remember which. > > > Yea, that sucks. Well, you could do this: > > $g->V()->has($id,Number::long(36)) ==> g.V().has("id",36l) > > This would, of course, bind you to Gremlin-Groovy as the ultimate > ScriptEngine. > > Another example would be g.V().has(id, neq(m)) . We could imagine the > following PHP equivalent $g->V()->has(new Id(), Predicate::neq("m")) > where Id() is a class that helps us recognize this type, and neq() a > static method of Predicate. However "m" has to be passed as string and we > have no clue what m is... is this a string or a binding or a server side > variable? More on this in point *2.* > > > Well, this is the same problem in Gremlin-Java. where() is ALWAYS bindings > and has() is ALWAYS objects. Thus: > > $g->V()->where("a",Predicate::neq("m")) ==> g.V().where("a",neq("m")) // > again strings always get " "-wrappers. > > To close things off here there's also the case of signatures like > out(String... > edgeLabels) that need their own logic. > > > Again, just toString() each object in the array and insert commas between. > > $g->V()->out(["created","knows"]) ==> g.V().out("created","knows") > > > *Conclusion*: There's a lot of manual work that needs to go into > separating the logic between signatures and handling special cases. Part of > this can be automated if your language supports magic getters and setters > by parsing the javadocs for example. But not only is that an if, the rest > will still be manual. This step is maintenance heavy. > > > I see the biggest pains being: > > 1. Having to implement each method. > 2. Having to have helper classes for P, T, Order, Column, etc. > > This is simply a matter of fat fingering stuff in and not anything > implementation-wise that is problematic -- ????…. > > *2. Conflicts* > > Because we're manipulating strings it's really hard to tell a few items > appart (binding vs server variable vs string; Theres a reason why I > separate binding and variable). > > For instance in the example above of *gremlin :* g.V().has(id, neq(m)) vs > *PHP:* $g->V()->has(new Id(), Predicate::neq("m")) we don't know what to > make of m. Is this a binding or a string or even a variable that was > previously set in the session? There is no clean way of working around this. > > Firstly because bindings tend to be handled on a different layer than the > query builder. > Secondly because methods that will help in avoiding the conflicts will > also lose typing data. > For example : $g->V()->has(new Id(), > Predicate::neq(Query::variable("m"))) could generate the proper query by > outputting m without quotes but we don't know what type m is so in some > cases it might be tricky to select the proper signature. > > *Conclusion*: there are a number of ways around this point. We use > prefixes B_m or V_m and a hack to ignore signatures altogether when in this > scenario. It's not that these aren't solve-able they just aren't trivial. > > > Hm. Yea, I'm not to smart about sever variables. Out of my butt you could > create a "crazy String" for those an then do replaceAll-style updates. > > g.V().out("%%x") > > replaceAll("%%x",x) > > ? > > > *3. API* > > Why we would need traversal, graph, vertex and edge APIs are quite self > explanatory for everyday work with Gremlin. I'm just going to expose why we > would also require some Java classes as well. > > Because JSON is lossy by nature we often have to cast variables to certain > types. For example by submitting these kind of scripts : > g.V(1).property("date", > new Date(B_m)); with B_m = timestamp. This is just another case that is > difficult to cover. > > This adds onto the other points in making a gremlin language variant > non-trivial. > > All of the above can be worked around by using an injection method that > just appends a string to the query : $g->customStep("V().has(id, > neq(m))") but that's besides the point. > > > > Ah. Classy. Note that in ?3.2.1? we might support script()-step. > > g.V().script("out().map{ it.name }") > > …to enable lambdas in remote'd traversals (Server or OLAP). > > For your Date example, you would have to have a special "toString()" for > PHP dates to Java dates (or whichever backend ScriptEngine is being used). > > $g->V()->property("data", phpDate) > > Your Array-string-ifier would not just call toString() blindly on the > objects of the array arguments, but would do stuff like: > > if(object instanceof String) > return \" + object.toString() + "\; > else if(object instanceof Date) > return "new Date(…)"; > else > return object.toString() > > > > *Final Conclusion:* It's not a trivial task. Of course the examples above > are very verbose and achieving something closer to gremlin in style is > possible but there are always going to be "gotchas" users will need to keep > in mind. A while back in TP2 I released a php library for this (the one we > currently use in our projects). I decided to remove it as it was too much > maintenance to get it to work across user causes so I decided to > concentrate on our own one (some choices made in *2.* wouldn't have > worked for other cases) > I'm convinced there's got to be a way of reconciling everything and > getting this to work flawlessly but it's going to require a lot of > thought/work > > > PS: I mentioned some other points like managing multiple versions of > gremlin (for two lines of releases) which is a real headache. > For performance it may be good to allow the builder to handle multiple > lines, which comes with it's load of complications as well. > And then there's the ability to "block" queries and either inject them > into each other or merge them together which simplifies unit testing and > extends functionality : > > $query = $g->V()->out("likes")->flag("flagname")->has("age", 20); > // Some logic here accesses new information and realizes the query needs > altering > $query->getFlag("flagname")->out("hates", true) // true for merge > $query->toString(); // g.V().out('likes', hates').has('age', 20) > > But this point alone could warrant it's own email as it is relatively > complex. Though TP3 has simplified some cases thanks to union() and some > other steps. > > Our builder supports all of the above so if you have any questions feel > free to ask me. > > Phew that was long. I'll add this to the ticket in a bit. > > > > Yes, maintenance seems the biggest pain. Every new method to Gremlin-Java > requires updates to Gremlin-PHP ---- perhaps there is a programmatic way to > introspect the Java source file (or JavaDoc) and generate the code > automagically? > > public GraphTraversal out(final String… edgeLabels) > ==auto-write==> > out(Array… edgeLabels) { > $string -> $string + ".out(" + StringHelper::toString(edgeLabels) + ")"; > } > > > If you could do that, then the only code you actually have to > write/maintain (besides the introspector above) is StringHelper which does > all the fancy String conversion of arguments. > > ??. > > Thanks Dylan for your time, > Marko. > > http://markorodriguez.com > > > On Tue, Apr 12, 2016 at 4:37 PM, Marko Rodriguez <okram...@gmail.com> > wrote: > > Hello everyone, > > Please see the section entitled "Host Language Embedding" here: > http://www.planettinkerpop.org/#gremlin (3 sections down) > > When I was writing up this section, I noticed that most of the language > drivers that are advertised on our homepage ( > http://tinkerpop.incubator.apache.org/#graph-libraries) know how to talk > to Gremlin Server via web sockets, REST, etc., but rely on the user to > create a String of their graph traversal and submit it. For instance, here > is a snippet from the Gremlin-PHP documentation: > > $db = new Connection([ > 'host' => 'localhost', > 'graph' => 'graph', > 'username' => 'pomme', > 'password' => 'hardToCrack' > ]); > //you can set $db->timeout = 0.5; if you wish > $db->open(); > $db->send('g.V(2)'); > //do something with result > $db->close(); > > > $db->send(String) is great, but it would be better if the user didn't have > to leave PHP. > > Please see this ticket: > https://issues.apache.org/jira/browse/TINKERPOP-1232 > > I think for non-JVM languages, it would be nice if these drivers (PHP, > JavaScript, Python, etc.) didn't require the user to explicitly create > Gremlin-XXX Strings, but instead either used JINI or model-3 in the ticket > above. Lets look at model-3 as I think its the easiest and more general. > > For instance, they would have a class in their native language that would > mirror the GraphTraversal API. *** I don't know any other languages well > enough, so I'm just going to do this in Groovy :), hopefully you get the > generalized point. *** > > public class Test { > > String > > ...
