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<p class="MsoPlainText"><span style="font-size:12.0pt;font-family:"Times New Roman",serif">Hi,<o:p></o:p></span></p>
<p class="MsoPlainText"><span style="font-size:12.0pt;font-family:"Times New Roman",serif"><o:p> </o:p></span></p>
<p class="MsoPlainText"><span style="font-size:12.0pt;font-family:"Times New Roman",serif">I would like to bring your attention to my spec [1] (already approved) on capability APIs and would like to get feedback from API WG.<o:p></o:p></span></p>
<p class="MsoPlainText"><span style="font-size:12.0pt;font-family:"Times New Roman",serif"><o:p> </o:p></span></p>
<p class="MsoPlainText"><span style="font-size:12.0pt;font-family:"Times New Roman",serif">To summarize, I propose defining a capability API for every resource in a REST API where it makes sense and is needed. In the context of Cinder, we would have a capability
API at the root resource level (GET </span><span style="font-family:Consolas">/v3.x/{tenant_id}/capabilities</span><span style="font-size:12.0pt;font-family:"Times New Roman",serif">) that would return, e.g., [“volume-backup", “other-capability”]. Similarly,
we could have a capability API on the volume types resource </span><span style="font-family:Consolas">(GET /v3.x/{tenant_id}/types/{volume_type_id}/capabilities</span><span style="font-size:12.0pt;font-family:"Times New Roman",serif">) that would return all
the features supported by a volume type and so on.<o:p></o:p></span></p>
<p class="MsoPlainText"><span style="font-size:12.0pt;font-family:"Times New Roman",serif"><o:p> </o:p></span></p>
<p class="MsoPlainText"><span style="font-size:12.0pt;font-family:"Times New Roman",serif">I believe that this API pattern solves the problem of exposing capabilities and could be used for enabling/disabling UI widgets on Horizon and other clients. This pattern
cleanly translates to all OpenStack projects which all face the general problem.<o:p></o:p></span></p>
<p class="MsoPlainText"><span style="font-size:12.0pt;font-family:"Times New Roman",serif"><o:p> </o:p></span></p>
<p class="MsoPlainText"><span style="font-size:12.0pt;font-family:"Times New Roman",serif">Can you please look at the spec (and the implementation for Cinder [2]) and let me know if you have any feedback? I would be most interested in knowing your thoughts
about cross-project suitability of this solution.<o:p></o:p></span></p>
<p class="MsoPlainText"><span style="font-size:12.0pt;font-family:"Times New Roman",serif"><o:p> </o:p></span></p>
<p class="MsoPlainText"><span style="font-size:12.0pt;font-family:"Times New Roman",serif">Thanks,<o:p></o:p></span></p>
<p class="MsoPlainText"><span style="font-size:12.0pt;font-family:"Times New Roman",serif">Deepti<o:p></o:p></span></p>
<p class="MsoPlainText"><span style="font-size:12.0pt;font-family:"Times New Roman",serif"><o:p> </o:p></span></p>
<p class="MsoPlainText"><span style="font-size:12.0pt;font-family:"Times New Roman",serif">[1]
<a href="https://review.openstack.org/#/c/306930/">https://review.openstack.org/#/c/306930/</a><o:p></o:p></span></p>
<p class="MsoPlainText"><span style="font-size:12.0pt;font-family:"Times New Roman",serif">[2]
<a href="https://review.openstack.org/#/c/350310/">https://review.openstack.org/#/c/350310/</a><o:p></o:p></span></p>
<p class="MsoPlainText"><o:p> </o:p></p>
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