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<p class="MsoNormal">Hi all,<o:p></o:p></p>
<p class="MsoNormal">I have some confusions on Sahara conductor codes. Maybe the questions are silly, but please let me know if you have the answer. Thanks.<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">1.<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>In Sahara conf we have an option “db_driver”, whose default value is “sahara.db”. Is it possible we do not use sahara.db? I think it should be the only choice for Sahara, so why do we have this option? For different db engine backend
we already have another option “db_backend” whose default value is “sqlalchemy”.<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">2.<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>In sahara/db/ directory we have a base.py, which defines Base class where use the db_driver to initialize self.db in Base. Thus we have below calling sequence (use cluster_create method as an example):
<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in">sahara.conductor.manager.ConductorManager().cluster_create <span style="font-family:Wingdings">è</span> sahara.db.Base().db.cluster_create
<span style="font-family:Wingdings">è</span> sahara.db.cluster_create <span style="font-family:Wingdings">
è</span> sahara.db.api.cluster_create <span style="font-family:Wingdings">è</span> IMPL.cluster_create<o:p></o:p></p>
<p class="MsoNormal"> So why we do not just discard base.py, and assign sahara.conductor.manager.ConductorManager().db_api = sahara.db.api, and let the flow be like
<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in;text-indent:.5in">sahara.conductor.manager.ConductorManager().cluster_create <span style="font-family:Wingdings">è</span> sahara.db_api.cluster_create
<span style="font-family:Wingdings">è</span> IMPL.cluster_create ?<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in">This is what Heat codes is like. Current Sahara implementation seems copied from nova. There we also have a “db_driver” whose default value is “nova.db”. In fact I also have the similar questions on nova (“db_driver”
and base.py seem redundant).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks.<o:p></o:p></p>
<p class="MsoNormal">-Ken<o:p></o:p></p>
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