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<div style="direction: ltr;font-family: Tahoma;color: #000000;font-size: 10pt;">The Images API v2 has been using PATCH to update an image record for quite a long time now. We pretty much follow the IETF docs. Here's how it's documented:<br>
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<a href="http://docs.openstack.org/api/openstack-image-service/2.0/content/update-an-image.html" target="_blank">http://docs.openstack.org/api/openstack-image-service/2.0/content/update-an-image.html</a><br>
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And here's the info about the media type used for the request body:<br>
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http://docs.openstack.org/api/openstack-image-service/2.0/content/appendix-b-http-patch-media-types.html<br>
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Not surprisingly, we feel that this is the correct way to implement PATCH!<br>
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cheers,<br>
brian<br>
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<div style="direction: ltr;" id="divRpF175941"><font color="#000000" face="Tahoma" size="2"><b>From:</b> Amit Gandhi [amit.gandhi@RACKSPACE.COM]<br>
<b>Sent:</b> Friday, December 12, 2014 3:17 PM<br>
<b>To:</b> OpenStack Development Mailing List (not for usage questions)<br>
<b>Subject:</b> [openstack-dev] [api] Usage of the PATCH verb<br>
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<div>Hi<br class="">
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We are currently using PATCH in the Poppy API to update existing resources. However, we have recently had some discussions on how this should have been implemented. <br class="">
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I would like to get the advise of the Openstack Community and the API working group on how PATCH semantics should work.<br class="">
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The following RFC documents [1][2] (and a blog post [3]) advise the using PATCH as the following:<br class="">
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2.1. A Simple PATCH Example
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<div class=""> PATCH /file.txt HTTP/1.1</div>
<div class=""> Host: <a href="http://www.example.com" class="" target="_blank">
www.example.com</a></div>
<div class=""> Content-Type: application/example</div>
<div class=""> If-Match: "e0023aa4e"</div>
<div class=""> Content-Length: 100</div>
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[
<div class=""><span class="Apple-tab-span" style="white-space:pre"></span>{ "op": "test", "path": "/a/b/c", "value": "foo" },</div>
<div class=""><span class="Apple-tab-span" style="white-space:pre"></span>{ "op": "remove", "path": "/a/b/c" },</div>
<div class=""><span class="Apple-tab-span" style="white-space:pre"></span>{ "op": "add", "path": "/a/b/c", "value": [ "foo", "bar" ] },</div>
<div class=""><span class="Apple-tab-span" style="white-space:pre"></span>{ "op": "replace", "path": "/a/b/c", "value": 42 },</div>
<div class=""><span class="Apple-tab-span" style="white-space:pre"></span>{ "op": "move", "from": "/a/b/c", "path": "/a/b/d" },</div>
<div class=""><span class="Apple-tab-span" style="white-space:pre"></span>{ "op": "copy", "from": "/a/b/d", "path": "/a/b/e" }</div>
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Basically, the changes consist of an operation, the path in the json object to modify, and the new value.
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<div class="">The way we currently have it implemented is to submit just the changes, and the server applies the change to the resource. This means passing entire lists to change etc.</div>
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<div class="">I would like to hear some feedback from others on how PATCH should be implemented.</div>
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<div class="">Thanks</div>
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<div class="">Amit Gandhi</div>
<div class="">- Rackspace</div>
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[1] <a href="https://tools.ietf.org/html/rfc5789" class="" target="_blank">https://tools.ietf.org/html/rfc5789</a><br class="">
[2] <a href="http://tools.ietf.org/html/rfc6902" class="" target="_blank">http://tools.ietf.org/html/rfc6902</a><br class="">
[3] <a href="http://williamdurand.fr/2014/02/14/please-do-not-patch-like-an-idiot/" class="" target="_blank">http://williamdurand.fr/2014/02/14/please-do-not-patch-like-an-idiot/</a><br class="">
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