Here is an initial pass at a Kafka REST proxy (in Scala) https://github.com/mumrah/kafka/blob/rest/contrib/rest-proxy/src/main/scala/RESTServer.scala
The basic gist is: * Jetty for webserver * Messages are strings * GET /topic/group to get a message (timeout after 1s) * POST /topic, the request body is the message * One consumer thread per topic+group Be wary, many things are hard coded at this point (port numbers, etc). Obviously, this will need to change. Also, I haven't the slightest idea how to setup/use sbt properly, so I just checked in the libs. Feedback is welcome in this thread or on Github. Be gentle please, this is my first go at Scala -David On Aug 12, 2012, at 10:39 AM, Taylor Gautier wrote: > Jay I agree with you 100%. > > At Tagged we have implemented a proxy for various internal reasons ( > primarily to act as a high performance relay from PHP to Kafka). It's > implemented in Node.js (JavaScript) > > Currently it services UDP packets encoded in binary but it could > easily be modified to accept http also since Node support for http is > pretty simple. > > If others are interested in maintaining something like this we could > consider adding this to the public domain along side the already > existing Node.js client implementation. > > > > On Aug 10, 2012, at 3:51 PM, Jay Kreps <jay.kr...@gmail.com> wrote: > >> My personal preference would be to have only a single protocol in kafka >> core. I have been down the multiple protocol route and my experience was >> that it adds a lot of burden for each change that needs to be made and a >> lot of complexity to abstract over the different protocols. From the point >> of view of a user they are generally a bit agnostic as to how bytes are >> sent back and forth provided it is reliable and easily implementable in any >> language. Generally they care more about the quality of the client in their >> language of choice. >> >> My belief is that the main benefit of REST is ease of implementing a >> client. But currently the biggest barrier is really the use of zk and >> fairly thick consumer design. So I think the current thinking is that we >> should focus on thinning that out and removing the client-side zk >> dependency. I actually don't think TCP is a huge burden if the protocol is >> simple, and there are actually some advantages (for example the consumer >> needs to consume from multiple servers so select/poll/epoll is natural but >> this is not always available from HTTP client libraries). >> >> Basically this is an area where I think it is best to pick one way and >> really make it really bullet proof rather than providing lots of options. >> In some sense each option tends to increase the complexity of testing >> (since now there are many combinations to try) and also of implementation >> (since now a lot things that were concrete now need to be abstracted away). >> >> So from this perspective I would prefer a standalone proxy that could >> evolve independently rather than retro-fitting the current socket server to >> handle other protocols. There will be some overhead for the extra hop, but >> then there is some overhead for HTTP itself. >> >> This is just my personal opinion, it would be great to hear what other >> think. >> >> -Jay >> >> On Mon, Aug 6, 2012 at 5:39 AM, David Arthur <mum...@gmail.com> wrote: >> >>> I'd be happy to collaborate on this, though it's been a while since I've >>> used PHP. >>> >>> From what it looks like, what you have is a true proxy that runs outside >>> of Kafka and translates some REST routes into Kafka client calls. This >>> sounds more in line with what the project page describes. What I have >>> proposed is more like a translation layer between some REST routes and >>> FetchRequests. In this case the client is responsible for managing offsets. >>> Using the consumer groups and ZooKeeper would be another nice way of >>> consuming messages (which is probably more like what you have). >>> >>> Any maintainers have feedback on this? >>> >>> On Aug 3, 2012, at 4:13 PM, Jonathan Creasy wrote: >>> >>>> I have an internal one working and was hoping to have it open sourced in >>>> the next week. The one at Box is based on the CodeIgniter framework, we >>>> have about 45 RESTful interfaces built on this framework so I just put >>>> together another one for Kafka. >>>> >>>> >>>> Here are my notes, these were pre-dev so may be a little different than >>>> what we ended up with. >>>> >>>> https://cwiki.apache.org/confluence/display/KAFKA/Restful+API+Proposal >>>> >>>> I will read yours later this afternoon, we should work together. >>>> >>>> -Jonathan >>>> >>>> >>>> On Fri, Aug 3, 2012 at 7:41 AM, David Arthur <mum...@gmail.com> wrote: >>>> >>>>> I'd like to tackle this project (assuming it hasn't been started yet). >>>>> >>>>> I wrote up some initial thoughts here: https://gist.github.com/3248179 >>>>> >>>>> TLDR; use Range header for specifying offsets, simple URIs like >>>>> /kafka/topics/[topic]/[partition], use for a simple transport of bytes >>>>> and/or represent the messages as some media type (text, json, xml) >>>>> >>>>> Feedback is most welcome (in the Gist or in this thread). >>>>> >>>>> Cheers! >>>>> >>>>> -David >>> >>>
