That's great news indeed! Maybe there should be a place on mesos site mentioning such efforts?
On Mon, Apr 28, 2014 at 5:24 AM, Brian Wickman <wick...@gmail.com> wrote: > To my knowledge there is no Zookeeper Group implementation for Go yet. > There do however appear to be Go zookeeper > bindings<https://github.com/samuel/go-zookeeper>. > From my day of spelunking through code, it seems that probably the most > challenging thing will be getting a ZookeeperMasterDetector implementation > working correctly to enable Scheduler "high availability" mode for these > other languages. > > Java/Python/C++ have the benefit of preexisting Group implementations > (java< > https://github.com/twitter/commons/blob/master/src/java/com/twitter/common/zookeeper/Group.java > > > , python< > https://github.com/twitter/commons/blob/master/src/python/twitter/common/zookeeper/group/kazoo_group.py > > > , c++< > https://git-wip-us.apache.org/repos/asf?p=mesos.git;a=blob;f=src/zookeeper/group.cpp;h=70972980dd25618c76eb36e0a31d060c096e36dc;hb=HEAD > >) > which are the foundation for ZK master detection. An intermediate option > could be to pull the ZookeeperMasterDetectorProcess out into a standalone > binary and have the native implementation talk to it as a sort of proxy to > figure out who the leading master is. But that's not nearly as satisfying > as a pure language implementation. > > ~brian > > > On Sun, Apr 27, 2014 at 3:22 PM, Vladimir Vivien > <vladimir.viv...@gmail.com>wrote: > > > It must be the right time for this. I started the same effort for Go. > > I am following Kevin's example and Ben's well-documented email (in this > > thread). > > Very early but should have some proof-of-concept working soon. > > > > https://github.com/vladimirvivien/ionos > > > > > > On Sun, Apr 27, 2014 at 6:07 PM, Tom Arnfeld <t...@duedil.com> wrote: > > > >> (Sorry to jump into this thread) > >> > >> I have to say, this is very exciting! It only became apparent to me how > >> painful it is having to compile the mesos egg into a Python framework > the > >> past week > >> while writing one, especially when running the framework on a different > >> architecture to the one running the executor! > >> > >> Looking forward to being able to use this. :-) > >> > >> It’d be awesome if the API was near identical, so one could switch > >> between `mesos` and `pesos` easily… > >> > >> Tom. > >> > >> On 27 Apr 2014, at 22:42, Brian Wickman <wick...@gmail.com> wrote: > >> > >> > And I've started a skeleton implementation of the Mesos framework API > at > >> > https://github.com/wickman/pesos > >> > > >> > While I vendored the translated protobuf, it would be great to tackle > >> > https://issues.apache.org/jira/browse/MESOS-857 at some point. > >> > > >> > > >> > On Sun, Apr 27, 2014 at 12:50 PM, Brian Wickman <wick...@gmail.com> > >> wrote: > >> > > >> >> I've implemented a pure python version of the basic > >> >> Process/ProtobufProcess mechanics and wire protocol. I haven't gone > >> so far > >> >> as Kevin and tried to register a framework or maybe talk to a > >> replicated > >> >> log, but it shouldn't be much more work: > >> >> > >> >> https://github.com/wickman/compactor > >> >> > >> >> Zero documentation but you can read the tests for a general idea of > >> what's > >> >> going on. > >> >> > >> >> cheers, > >> >> brian > >> >> > >> >> > >> >> > >> >> On Sun, Apr 13, 2014 at 10:28 PM, Kevin Sweeney < > >> kevin.t.swee...@gmail.com > >> >>> wrote: > >> >> > >> >>> I've got the start of a JVM verson on github - it can currently > >> register > >> >>> a framework and parse the response. Client-side I still need to > >> figure out > >> >>> how to properly configure Keep-Alive. Servlet can dispatch messages > to > >> >>> message handlers in a type-safe way and returns a 202 for messages > >> it's > >> >>> going to handle. Code's a mess currently. > >> >>> > >> >>> https://github.com/kevints/mesos-framework-api > >> >>> > >> >>> > >> >>> On Fri, Apr 11, 2014 at 7:12 PM, Benjamin Hindman < > >> b...@eecs.berkeley.edu > >> >>>> wrote: > >> >>> > >> >>>> First, my apologies for getting to this party so late. It's great > to > >> see > >> >>>> people interested in helping create native-language Mesos > libraries. > >> >>>> > >> >>>> Vladimir: my presentation was definitely referring to the the > >> low-level > >> >>>> protocol between master, framework (scheduler), slave, and > >> executors. I'll > >> >>>> do my best here to clarify how the current protocol works and what > >> we need > >> >>>> to do to get it to the point where we can write native-language > >> libraries. > >> >>>> (Eventually it would be great to move some of this into > >> documentation as > >> >>>> necessary.) > >> >>>> > >> >>>> As Nikita pointed out, the protocol is currently "HTTP-like". As my > >> >>>> presentation describes, think actors and one-way message passing > when > >> >>>> considering how the protocol works. > >> >>>> > >> >>>> To send a message an actor POSTs an HTTP request where the actor > >> that is > >> >>>> supposed to receive the message is the first component of the > >> request path > >> >>>> and the name of the message is the remaining part of the path. To > >> >>>> distinguish one of these "messages" from a normal HTTP request we > >> look to > >> >>>> see if the 'User-Agent' is 'libprocess/...'. For example: > >> >>>> > >> >>>> POST /master/mesos.internal.RegisterFrameworkMessage HTTP/1.1 > >> >>>> User-Agent: libprocess/scheduler(1)@10.0.1.7:53523 > >> >>>> > >> >>>> ... represents a message with the name > >> >>>> 'mesos.internal.RegisterFrameworkMessage' destined for the actor > >> 'master' > >> >>>> coming from the actor 'scheduler(1)' at 10.0.1.7:53523. If the > >> 'master' > >> >>>> actor were to send a message back it would look something like > this: > >> >>>> > >> >>>> POST /scheduler(1)/mesos.internal.FrameworkRegisteredMessage > HTTP/1.1 > >> >>>> User-Agent: libprocess/master@10.0.1.7:5050 > >> >>>> > >> >>>> So, one-way message passing via HTTP POST. > >> >>>> > >> >>>> The message data is captured as the body of the HTTP request (which > >> can > >> >>>> be specified using _either_ Content-Length or a Transfer-Encoding, > >> and as > >> >>>> Nikita points out we use chunked transfer encoding internally). The > >> data is > >> >>>> arbitrary and the actor ultimately decides how it wants to "parse" > >> it. In > >> >>>> Mesos, 99% of our messages use serialized protobufs, but we also > >> send a few > >> >>>> messages with just arbitrary data. All this really means is that > >> knowing > >> >>>> the actor and message name is not enough, you also need to know > what > >> the > >> >>>> body type is supposed to be for that message. In the future we'll > >> probably > >> >>>> enable messages with either JSON or serialized protobuf[1] ... for > >> now, > >> >>>> just serialized protobuf. > >> >>>> > >> >>>> Okay, so where does this break down when trying to do this > >> >>>> language-natively? I've had some of this in the works and this > >> conversation > >> >>>> has motivated me to publish some reviews addressing the issues: > >> >>>> > >> >>>> (1) We'll need to return a response if one plans to use a native > HTTP > >> >>>> library since it'll expect request/response. > >> >>>> https://reviews.apache.org/r/20276 introduces responding with a > '202 > >> >>>> Accepted' for these messages (from the HTTP specification, a '202 > >> >>>> Accepted': "The request has been accepted for processing, but the > >> >>>> processing has not been completed. The request might or might not > >> >>>> eventually be acted upon, as it might be disallowed when processing > >> >>>> actually takes place. There is no facility for re-sending a status > >> code > >> >>>> from an asynchronous operation such as this."). > >> >>>> > >> >>>> (2) Most HTTP libraries will set their 'User-Agent' themselves, so > >> >>>> https://reviews.apache.org/r/20277 introduces a 'libprocess-from' > >> >>>> header that works similar to User-Agent. There is still some > cleanup > >> I'd > >> >>>> love to do around stringification of PIDs (the underlying type > Mesos > >> uses > >> >>>> for remote actors, inspired by Erlang). Until then, the > >> 'libprocess-from' > >> >>>> string is unfortunately esoteric (see the test). > >> >>>> > >> >>>> The combination of these two patches should make sending and > >> receiving > >> >>>> messages straightforward. However, we still plan to expose the > >> low-level > >> >>>> Event and Call protobuf messages and that will be the preferred > >> approach > >> >>>> for building a native-language library. Follow along at > >> >>>> https://issues.apache.org/jira/browse/MESOS-1127 for more details. > >> (To > >> >>>> be clear, you'd still be able to implement native-language > libraries > >> with > >> >>>> the patches above but we'll be deprecating the protobufs you'd be > >> using in > >> >>>> favor of Event and Call protobufs instead. If you're eager to get > >> that > >> >>>> going before Event and Call are committed I'm happy to discuss the > >> existing > >> >>>> protobufs in more detail.) > >> >>>> > >> >>>> I hope this helps. > >> >>>> > >> >>>> Ben. > >> >>>> > >> >>>> > >> >>>> On Fri, Apr 11, 2014 at 4:54 AM, Vladimir Vivien < > >> >>>> vladimir.viv...@gmail.com> wrote: > >> >>>> > >> >>>>> Nikita > >> >>>>> Thanks for the JIRA. > >> >>>>> > >> >>>>> > >> >>>>> On Wed, Apr 9, 2014 at 2:16 PM, Vetoshkin Nikita < > >> >>>>> nikita.vetosh...@gmail.com > >> >>>>>> wrote: > >> >>>>> > >> >>>>>> BTW, there is also somehow related ticket > >> >>>>>> https://issues.apache.org/jira/browse/MESOS-930 > >> >>>>>> > >> >>>>>> > >> >>>>>> On Wed, Apr 9, 2014 at 9:54 PM, Benjamin Mahler > >> >>>>>> <benjamin.mah...@gmail.com>wrote: > >> >>>>>> > >> >>>>>>>> > >> >>>>>>>> I thought the low-level api being referred in the > >> >>>>>>>> video had to do with communication between master and > >> >>>>>> framework|executor > >> >>>>>>>> for scheduling. But, it's really administrative. I thought > that > >> >>>>> would > >> >>>>>>>> have been an opportunity for a Go binding that did not require > >> >>>>> the C++ > >> >>>>>>>> libraries. > >> >>>>>>>> > >> >>>>>>> > >> >>>>>>> Vladimir, the low-level API referred to in the talk is exactly > >> what > >> >>>>>> you're > >> >>>>>>> interpreting, it is for communication between master and > >> scheduler, > >> >>>>> and > >> >>>>>>> slave and executor. You could definitely build pure go bindings > as > >> >>>>> you > >> >>>>>>> described, just not with JSON. > >> >>>>>>> > >> >>>>>>> Forget I mentioned anything about the administrative endpoints > and > >> >>>>> JSON, > >> >>>>>> as > >> >>>>>>> I see that's leading to confusion. ;) > >> >>>>>>> > >> >>>>>>> On Wed, Apr 9, 2014 at 3:39 AM, Vladimir Vivien > >> >>>>>>> <vladimir.viv...@gmail.com>wrote: > >> >>>>>>> > >> >>>>>>>> Ben, > >> >>>>>>>> Thank you for clarifying. I thought the low-level api being > >> >>>>> referred in > >> >>>>>>> the > >> >>>>>>>> video had to do with communication between master and > >> >>>>>> framework|executor > >> >>>>>>>> for scheduling. But, it's really administrative. I thought > that > >> >>>>> would > >> >>>>>>>> have been an opportunity for a Go binding that did not require > >> >>>>> the C++ > >> >>>>>>>> libraries. > >> >>>>>>>> > >> >>>>>>>> Thanks anyway. > >> >>>>>>>> > >> >>>>>>>> > >> >>>>>>>> > >> >>>>>>>> > >> >>>>>>>> > >> >>>>>>>> > >> >>>>>>>> On Tue, Apr 8, 2014 at 4:52 PM, Benjamin Mahler > >> >>>>>>>> <benjamin.mah...@gmail.com>wrote: > >> >>>>>>>> > >> >>>>>>>>> Sorry, I was not referring to implementing a scheduler via > JSON > >> >>>>>> instead > >> >>>>>>>> of > >> >>>>>>>>> protobuf, in theory that would be possible but there has been > no > >> >>>>>>> planning > >> >>>>>>>>> in this area. Sorry for the confusion. > >> >>>>>>>>> > >> >>>>>>>>> I was referring to administrative endpoints. For example, > >> >>>>> kicking a > >> >>>>>>>>> framework out or telling the master a slave is needs to be > >> >>>>> repaired. > >> >>>>>>>> These > >> >>>>>>>>> endpoints may rely on the ability to convert JSON to internal > >> >>>>>>> protobufs. > >> >>>>>>>>> > >> >>>>>>>>> Can you clarify what you're looking to do? Are you looking to > >> >>>>>> implement > >> >>>>>>>> an > >> >>>>>>>>> API in Go that communicates with JSON instead of serialized > >> >>>>> protobuf? > >> >>>>>>>>> > >> >>>>>>>>> On Tue, Apr 8, 2014 at 1:19 PM, Vladimir Vivien > >> >>>>>>>>> <vladimir.viv...@gmail.com>wrote: > >> >>>>>>>>> > >> >>>>>>>>>> Ben, > >> >>>>>>>>>> That is exactly what I am asking. > >> >>>>>>>>>> Is that something coming up soon, is there a JIRA I can look > >> >>>>> at? > >> >>>>>>>>>> I wanna get early start on a native json Go api or even help > >> >>>>> out if > >> >>>>>>>>>> possible. > >> >>>>>>>>>> > >> >>>>>>>>>> > >> >>>>>>>>>> On Tue, Apr 8, 2014 at 3:25 PM, Benjamin Mahler > >> >>>>>>>>>> <benjamin.mah...@gmail.com>wrote: > >> >>>>>>>>>> > >> >>>>>>>>>>> +vinod, benh > >> >>>>>>>>>>> > >> >>>>>>>>>>> Hey Vladimir, there will be some authenticated REST > >> >>>>> endpoints at > >> >>>>>>> some > >> >>>>>>>>>>> point, there is some work in this area underway. > >> >>>>>>>>>>> > >> >>>>>>>>>>> We have the ability to encode protobuf messages as JSON, so > >> >>>>> the > >> >>>>>>> plan > >> >>>>>>>>> was > >> >>>>>>>>>> to > >> >>>>>>>>>>> have any REST endpoints directly use JSON to send us > >> >>>>> protobuf > >> >>>>>>>> messages. > >> >>>>>>>>>> I'm > >> >>>>>>>>>>> not sure if this is what you're asking though? > >> >>>>>>>>>>> > >> >>>>>>>>>>> > >> >>>>>>>>>>> On Tue, Apr 8, 2014 at 11:13 AM, Vetoshkin Nikita < > >> >>>>>>>>>>> nikita.vetosh...@gmail.com> wrote: > >> >>>>>>>>>>> > >> >>>>>>>>>>>> I'm not a mesos guy, just very curious. But in my opinion > >> >>>>> - I > >> >>>>>>> doubt > >> >>>>>>>>> it, > >> >>>>>>>>>>>> HTTP is synchronous request-response protocol. Mesos needs > >> >>>>>>>> something > >> >>>>>>>>>> more > >> >>>>>>>>>>>> robust for message passing. Websockets anyone? :) > >> >>>>>>>>>>>> > >> >>>>>>>>>>>> > >> >>>>>>>>>>>> On Tue, Apr 8, 2014 at 10:08 PM, Vladimir Vivien > >> >>>>>>>>>>>> <vladimir.viv...@gmail.com>wrote: > >> >>>>>>>>>>>> > >> >>>>>>>>>>>>> Ben / Nikita > >> >>>>>>>>>>>>> Thanks for the pointers. > >> >>>>>>>>>>>>> So, (without digging yet) is it a fair summary to say > >> >>>>> that > >> >>>>>>>>> libprocess > >> >>>>>>>>>>>> wraps > >> >>>>>>>>>>>>> protobufs-encoded calls and push them over HTTP to > >> >>>>>>> master/slaves > >> >>>>>>>> ? > >> >>>>>>>>>> Will > >> >>>>>>>>>>>>> protobuf (eventually) be supplanted by direct HTTP via > >> >>>>> REST > >> >>>>>> or > >> >>>>>>>>>> similar > >> >>>>>>>>>>> ? > >> >>>>>>>>>>>>> > >> >>>>>>>>>>>>> > >> >>>>>>>>>>>>> On Mon, Apr 7, 2014 at 2:54 PM, Vetoshkin Nikita < > >> >>>>>>>>>>>>> nikita.vetosh...@gmail.com > >> >>>>>>>>>>>>>> wrote: > >> >>>>>>>>>>>>> > >> >>>>>>>>>>>>>> Or, just to get to know - you can take tcpdump and > >> >>>>> take a > >> >>>>>>> look > >> >>>>>>>> :) > >> >>>>>>>>>>>>>> > >> >>>>>>>>>>>>>> I personally wouldn't call that HTTP. Something > >> >>>>> "HTTP-like" > >> >>>>>>>> would > >> >>>>>>>>>>>>> describe > >> >>>>>>>>>>>>>> it better. Because it's not request-response. It's > >> >>>>> just > >> >>>>>>> message > >> >>>>>>>>>>>> passing, > >> >>>>>>>>>>>>> no > >> >>>>>>>>>>>>>> need to wait for the answer - send new message one > >> >>>>> after > >> >>>>>>>> another. > >> >>>>>>>>>>> Every > >> >>>>>>>>>>>>>> message is POST with address and message type encoded > >> >>>>> in > >> >>>>>> URI: > >> >>>>>>>>> POST > >> >>>>>>>>>>>>>> /executor(1)/mesos.internal.RunTaskMessage. Sender is > >> >>>>>> encoded > >> >>>>>>>> in > >> >>>>>>>>>>>>> User-Agent > >> >>>>>>>>>>>>>> header, e.g: libprocess/slave(1)@127.0.0.1:5051. Body > >> >>>>>>> contains > >> >>>>>>>>>>>> protobuf > >> >>>>>>>>>>>>>> message, Transfer-Encoding is always "chunked". > >> >>>>>>>>>>>>>> > >> >>>>>>>>>>>>>> > >> >>>>>>>>>>>>>> On Mon, Apr 7, 2014 at 10:42 PM, Benjamin Mahler > >> >>>>>>>>>>>>>> <benjamin.mah...@gmail.com>wrote: > >> >>>>>>>>>>>>>> > >> >>>>>>>>>>>>>>> Unfortunately you will need to learn this by > >> >>>>> looking at > >> >>>>>> the > >> >>>>>>>>> code > >> >>>>>>>>>> in > >> >>>>>>>>>>>>>>> libprocess, as the message passing format is not > >> >>>>>> explicitly > >> >>>>>>>>>>>> documented > >> >>>>>>>>>>>>> at > >> >>>>>>>>>>>>>>> the current time. > >> >>>>>>>>>>>>>>> > >> >>>>>>>>>>>>>>> Start with calls like ProtobufProcess::send() and > >> >>>>> dig > >> >>>>>> your > >> >>>>>>>> way > >> >>>>>>>>>>> down. > >> >>>>>>>>>>>>>>> > >> >>>>>>>>>>>>>>> > >> >>>>>>>>>>>>>>> On Sat, Apr 5, 2014 at 7:52 AM, Vladimir Vivien > >> >>>>>>>>>>>>>>> <vladimir.viv...@gmail.com>wrote: > >> >>>>>>>>>>>>>>> > >> >>>>>>>>>>>>>>>> I was watching this video from > >> >>>>>>>>>>>>>>>> https://www.youtube.com/watch?v=n5GT7OFSh58fromBen > >> >>>>>>> where > >> >>>>>>>> he > >> >>>>>>>>>>>> talked > >> >>>>>>>>>>>>>>>> about the wire protocol for Mesos being done in > >> >>>>>>>>>>>>>>>> HTTP. > >> >>>>>>>>>>>>>>>> > >> >>>>>>>>>>>>>>>> Where can I learn about the low-level wire > >> >>>>> protocol > >> >>>>>>> either > >> >>>>>>>> in > >> >>>>>>>>>>>>>>> documentation > >> >>>>>>>>>>>>>>>> or browsing through the code. > >> >>>>>>>>>>>>>>>> > >> >>>>>>>>>>>>>>>> Thanks. > >> >>>>>>>>>>>>>>>> > >> >>>>>>>>>>>>>>>> -- > >> >>>>>>>>>>>>>>>> Vladimir Vivien > >> >>>>>>>>>>>>>>>> > >> >>>>>>>>>>>>>>> > >> >>>>>>>>>>>>>> > >> >>>>>>>>>>>>> > >> >>>>>>>>>>>>> > >> >>>>>>>>>>>>> > >> >>>>>>>>>>>>> -- > >> >>>>>>>>>>>>> Vladimir Vivien > >> >>>>>>>>>>>>> > >> >>>>>>>>>>>> > >> >>>>>>>>>>> > >> >>>>>>>>>> > >> >>>>>>>>>> > >> >>>>>>>>>> > >> >>>>>>>>>> -- > >> >>>>>>>>>> Vladimir Vivien > >> >>>>>>>>>> > >> >>>>>>>>> > >> >>>>>>>> > >> >>>>>>>> > >> >>>>>>>> > >> >>>>>>>> -- > >> >>>>>>>> Vladimir Vivien > >> >>>>>>>> > >> >>>>>>> > >> >>>>>> > >> >>>>> > >> >>>>> > >> >>>>> > >> >>>>> -- > >> >>>>> Vladimir Vivien > >> >>>>> > >> >>>> > >> >>>> > >> >>> > >> >> > >> > >> > > > > > > -- > > Vladimir Vivien > > >
