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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">I’m pretty -1 on triggering changes in other projects from common. That’s gonna result in a broken code (whether subtle or obvious) no matter how good your
gates are.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">At least as an external library you can freeze a version requirement until such time as you see fit to properly updated that code and *<b>ensure</b>* compatibility
in your project.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Or if your project likes ridin’ trunk, then don’t pin a version and you’ve got the same effect as an automatic trigger.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
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<![if !supportLists]><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><span style="mso-list:Ignore">-<span style="font:7.0pt "Times New Roman"">
</span></span></span><![endif]><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Gabriel<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext"> openstack-bounces+gabriel.hurley=nebula.com@lists.launchpad.net
[mailto:openstack-bounces+gabriel.hurley=nebula.com@lists.launchpad.net] <b>On Behalf Of
</b>Andrew Bogott<br>
<b>Sent:</b> Tuesday, July 03, 2012 3:54 PM<br>
<b>To:</b> Eric Windisch; openstack@lists.launchpad.net<br>
<b>Subject:</b> Re: [Openstack] best practices for merging common into specific projects<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">On 7/3/12 5:47 PM, Eric Windisch wrote: <o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:9.0pt">git submodules don't have to be linked to the head of a branch. Instead of double-commiting (for every commit), we can do a single commit in each project to change the git reference of the submodule. This would
not be too far from the existing behavior, except that it would minimize the double commits.</span>
<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Oh, I guess I left out an important part of my vision, which is that there would be a commit hook in common which moves the submodule reference in the parent projects anytime a patch is merged in common. So, in short: once a patch passed
review for inclusion in common, that patch would automatically go live in all other project heads simultaneously.<br>
<br>
<br>
<o:p></o:p></p>
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<p class="MsoNormal">-- <br>
Eric Windisch <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p><span style="color:#A0A0A8">On Tuesday, July 3, 2012 at 15:47 PM, Andrew Bogott wrote:<o:p></o:p></span></p>
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<p class="MsoNormal">On 7/3/12 1:59 PM, Gabriel Hurley wrote:<o:p></o:p></p>
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<p class="MsoNormal">The notion that copying code is any protection against APIs that may change is a red herring. It's the exact same effect as pegging a version of a dependency (whether it's a commit hash or a real version number), except now you have code
duplication. An unstable upgrade path is an unstable upgrade path, and copying the code into the project doesn't alleviate the pain for the project if the upstream library decides to change its APIs.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Also, we're really calling something used by more or less all the core projects "incubated"? ;-) Seems like it's past the proof-of-concept phase now, at least for many parts of common. Questions of API stability are an issue unto themselves.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Anyhow, I'm +1 on turning it into a real library of its own, as a couple people suggested already.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">- Gabriel<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">I feel like I should speak up since I started this fight in the first
<o:p></o:p></p>
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<p class="MsoNormal">place :)<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Like most people in this thread, I too long for an end to the weird
<o:p></o:p></p>
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<p class="MsoNormal">double-commit process that we're using now. So I'm happy to set aside
<o:p></o:p></p>
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<p class="MsoNormal">my original Best Practices proposal until there's some consensus
<o:p></o:p></p>
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<p class="MsoNormal">regarding how much longer we're going to use that process. Presumably
<o:p></o:p></p>
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<p class="MsoNormal">opinions about how to handle merge-from-common commits will vary in the
<o:p></o:p></p>
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<p class="MsoNormal">meantime, but that's something we can live with.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">In terms of promoting common into a real project, though, I want to
<o:p></o:p></p>
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<p class="MsoNormal">raise another option that's guaranteed to be unpopular: We make
<o:p></o:p></p>
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<p class="MsoNormal">openstack-common a git-submodule that is automatically checked out
<o:p></o:p></p>
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<p class="MsoNormal">within the directory tree of each other project. Then each commit to
<o:p></o:p></p>
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<p class="MsoNormal">common would need to be gated by the full set of tests on every project
<o:p></o:p></p>
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<p class="MsoNormal">that includes common.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">I haven't thought deeply about the pros and cons of code submodule vs.
<o:p></o:p></p>
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<p class="MsoNormal">python project, but I want to bring up the option because it's the
<o:p></o:p></p>
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<p class="MsoNormal">system that I'm the most familiar with, and one that's been discussed a
<o:p></o:p></p>
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<p class="MsoNormal">bit off and on.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">-Andrew<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">_______________________________________________<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">Mailing list: <a href="https://launchpad.net/%7Eopenstack">https://launchpad.net/~openstack</a><o:p></o:p></p>
</div>
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<p class="MsoNormal">Post to : <a href="mailto:openstack@lists.launchpad.net">openstack@lists.launchpad.net</a><o:p></o:p></p>
</div>
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<p class="MsoNormal">Unsubscribe : <a href="https://launchpad.net/%7Eopenstack">https://launchpad.net/~openstack</a><o:p></o:p></p>
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