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<div id="bloop_customfont">I completely agree with you regarding separation of concerns. </div>
<div id="bloop_customfont"><br />
</div>
<div id="bloop_customfont">I also agree with your definitions: a transport client is for managing HTTP transactions, a service client contains all the domain logic for an API service (Swift, Nova, etc.). A service knows nothing about HTTP, a transport client
knows nothing about Swift. A transport client is injected into the service client, satisfying the type hint. So any transport client implementing our interface is fine.</div>
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<div>Up to this point I’m in 100% agreement. The area which I think I misunderstood was the
<i>creation process</i> of service clients. My take was that you were advocating a shared transport client instance - i.e. a transport client instantiated once, and re-used for every service client. If we did that, there would be global state. </div>
<div><br />
</div>
<div>My opinion is that we create a <b>new</b> transport client instance for every service client, not re-use existing instances. What’s your take on this?</div>
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<div>Jamie</div>
<br />
<p style=color:#000;>On June 5, 2014 at 5:17:57 PM, Matthew Farina (<a href="mailto:matt@mattfarina.com">matt@mattfarina.com</a>) wrote:</p>
<blockquote type="cite" class="clean_bq"><span>
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<div></div>
<div>We've started to talk about the interactions between transport <br />
clients, service clients, and state. I've noticed we're not on the <br />
same page so I wanted to start a dialog. Here's my starting point... <br />
<br />
A Transport Client is about transporting data. It sends and receives data. <br />
<br />
A Service Client handles the interactions with a service (e.g., swift, <br />
nova, keystone). <br />
<br />
A Service Client uses a Transport Client when it needs to transport <br />
data to and from a service. <br />
<br />
When it comes to state, a Transport Client knows about transporting <br />
things. That means it knows things like if there is a proxy and how to <br />
work with it. A Service Client knows about a service which includes <br />
and state for that service. <br />
<br />
In the realm of separation of concerns, a Service Client doesn't know <br />
about transport state and a Transport Client doesn't know about <br />
service state. They are separate. <br />
<br />
A Service Client doesn't care what Transport Client is used as long as <br />
the API (interface) is compliant. A Transport Client doesn't care what <br />
code calls it as long as it uses the public API defined by an <br />
interface. <br />
<br />
This is my take. If someone has a different take please share it with <br />
the reasoning. <br />
<br />
- Matt <br />
</div>
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