Re: Reactive REST

"Greg Young [email protected] [rest-discuss]" <[email protected]> Sat, 17 May 2014 20:34:43 +0300
Newsgroups gmane.comp.web.services.rest
Message-ID <CAC9RQtgbsZrASijbDy69+p1pj2SfDxKLU+m8SqcQnDxZer3w_A@mail.gmail.com>
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atom.

Cheers,

Greg


On Sat, May 17, 2014 at 8:33 PM, Michael Schuerig
[email protected][rest-discuss]
<[email protected]> wrote:

>
>
>
> The "reactive" buzzword has been conspicuously absent from this list.
> I'll try to fill this much needed gap.
>
> I've recently watched a presentation by Jafar Husain
>
> http://www.infoq.com/presentations/netflix-reactive-rest
>
> where he describes something he calls "Reactive REST". I agree on the
> "reactive", however I have doubts about the "REST". In this particular
> case, all communication between a client and a server is over persistent
> connection to a single endpoint. If there's anything resembling
> resources, they are not identified by URIs. The persistent connection
> IMHO is a case of "conversational" state that REST is rather opposed to.
> No HATEOAS in sight.
>
> What I'm pondering is whether an API can be RESTful and reactive at the
> same time or if is impossible as a matter of principle. AFAICT, a
> reactive API requires some way for the server to send events to the
> client. I don't think polling qualifies, which leaves a persistent
> connection. In effect, the server has to keep some amount of state for
> each session.
>
> Keeping session state has traditionally been regarded as a hindrance to
> scalability. Has technology advanced so much, eg with asynchronous,
> event-driven ("reactive") servers, that this is no longer a problem?
>
> Frankly, I'm lacking experience with systems where this kind of
> scalability would be required, so I'd happily use persistent
> connections, at least to begin with. Nonetheless, I'm interested in your
> insights.
>
> Michael
>
> --
> Michael Schuerig
> mailto:[email protected]
> http://www.schuerig.de/michael/
>=20=20
>



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      <p><div dir=3D"ltr">atom.<div><br></div><div>Cheers,</div><div><br></=
div><div>Greg</div></div><div class=3D"gmail_extra"><br><br><div class=3D"g=
mail_quote">On Sat, May 17, 2014 at 8:33 PM, Michael Schuerig <a href=3D"ma=
ilto:[email protected]">[email protected]</a> [rest-discuss=
] <span dir=3D"ltr">&lt;<a href=3D"mailto:[email protected]" tar=
get=3D"_blank">[email protected]</a>&gt;</span> wrote:<br>
<blockquote class=3D"gmail_quote" style=3D"border-left:1px #ccc solid;">


<u></u>









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      <p><br>
The &quot;reactive&quot; buzzword has been conspicuously absent from this l=
ist. <br>
I&#39;ll try to fill this much needed gap.<br>
<br>
I&#39;ve recently watched a presentation by Jafar Husain<br>
<br>
<a href=3D"http://www.infoq.com/presentations/netflix-reactive-rest" target=
=3D"_blank">http://www.infoq.com/presentations/netflix-reactive-rest</a><br=
>
<br>
where he describes something he calls &quot;Reactive REST&quot;. I agree on=
 the <br>
&quot;reactive&quot;, however I have doubts about the &quot;REST&quot;. In =
this particular <br>
case, all communication between a client and a server is over persistent <b=
r>
connection to a single endpoint. If there&#39;s anything resembling <br>
resources, they are not identified by URIs. The persistent connection <br>
IMHO is a case of &quot;conversational&quot; state that REST is rather oppo=
sed to. <br>
No HATEOAS in sight.<br>
<br>
What I&#39;m pondering is whether an API can be RESTful and reactive at the=
 <br>
same time or if is impossible as a matter of principle. AFAICT, a <br>
reactive API requires some way for the server to send events to the <br>
client. I don&#39;t think polling qualifies, which leaves a persistent <br>
connection. In effect, the server has to keep some amount of state for <br>
each session.<br>
<br>
Keeping session state has traditionally been regarded as a hindrance to <br=
>
scalability. Has technology advanced so much, eg with asynchronous, <br>
event-driven (&quot;reactive&quot;) servers, that this is no longer a probl=
em?<br>
<br>
Frankly, I&#39;m lacking experience with systems where this kind of <br>
scalability would be required, so I&#39;d happily use persistent <br>
connections, at least to begin with. Nonetheless, I&#39;m interested in you=
r <br>
insights.<br>
<br>
Michael<br>
<br>
-- <br>
Michael Schuerig<br>
mailto:<a href=3D"mailto:[email protected]" target=3D"_blank">michael@sch=
uerig.de</a><br>
<a href=3D"http://www.schuerig.de/michael/" target=3D"_blank">http://www.sc=
huerig.de/michael/</a><br>
</p>

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<div dir=3D"ltr">Studying for the Turing test</div>
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