<div>Thanks Bernd, </div>
<div> </div>
<div>I am working around this issues as you have suggested. </div>
<div> </div>
<div>- Shailesh</div>
<div><br><br> </div>
<div class="gmail_quote">On Nov 17, 2007 5:31 PM, Bernd Dorn <<a href="mailto:bernd.dorn@lovelysystems.com">bernd.dorn@lovelysystems.com</a>> wrote:<br>
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<div>On 16.11.2007, at 13:56, Shailesh Kumar wrote:</div><br>
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<div>As of now, I am thinking of a following solution. For the current upgrade, I will have some code which will automatically evolve the existing installation during startup</div>
<div>(i.e. DatabaseOpenedEvent) and actually assign a generation number in the root[generations_key]['product_name'] key.</div>
<div> </div>
<div>In the later upgrades, I will replace this with the regular schema manager.</div>
<div> </div>
<div>Comments from the zope 3 experts would be very useful.</div></span></blockquote><br></div></div>
<div>well this is a real flaw with generations ...</div>
<div><br></div>
<div>in our projects we always add an initial .generations package to avoid such cases, you can do this too, but it needs an intermediate version but no "dummy" schema manager.</div>
<div><br></div>
<div>in generations/__init__.py you add</div>
<div><br></div>
<div>
<div>from zope.app.generations.generations import SchemaManager</div>
<div><br></div>
<div>pkg = 'myapp'</div>
<div><br></div>
<div>schemaManager = SchemaManager(</div>
<div> minimum_generation=0,</div>
<div> generation=0,</div>
<div> package_name=pkg)</div><br></div>
<div>and register the manager.</div>
<div><br></div>
<div>make a realease, this will set the generation to 0</div>
<div><br></div>
<div>then add your first "evolve1.py" to generations, the manager stays the same - you only have to increase the generation number</div>
<div><br></div>
<div>regards, bernd</div>
<div><br></div>
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