Re: [Zope-dev] Question about import code
Shane Hathaway writes: Fred Wilson Horch wrote: Importing multiple objects simultaneously could result in a fair amount of confusion... Can you elaborate? When you import a folder, for example, it imports the folder and all objects in it. If there are some objects in the folder that have conflicting names and others that don't, what do you do? Zope already solves this problem for paste. Although, I am not sure that I like this solution, import should behave the same, for consistency. Also, if you're thinking about providing this functionality, what about spanning multiple folders? What if some folders already exist? Again, it should behave like paste, for consistency. Dieter ___ Zope-Dev maillist - [EMAIL PROTECTED] http://lists.zope.org/mailman/listinfo/zope-dev ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope )
Re: [Zope-dev] Question about import code
Fred Wilson Horch wrote: The problem that happens on import is a KeyError on line 194 of this bit of code: lines 192-197 of lib/python/ZODB/ExportImport.py ooid=h[:8] if oids: oid=oids[ooid] if type(oid) is TupleType: oid=oid[0] else: oids[ooid]=return_oid=oid=new_oid() If I change this code to ooid=h[:8] if oids and oids.has_key(ooid): oid=oids[ooid] if type(oid) is TupleType: oid=oid[0] else: oids[ooid]=return_oid=oid=new_oid() then the import appears to succeed, but only the final object in the file is actually imported. Importing multiple objects simultaneously could result in a fair amount of confusion... But if you really think it's a good idea, if you used a list called return_oids instead, and appended to this list in the code above, you'd probably get what you're looking for. ooid=h[:8] if oids and oids.has_key(ooid): oid=oids[ooid] if type(oid) is TupleType: oid=oid[0] else: oids[ooid] = oid = new_oid() return_oids.append(oid) Then at the end of the function you'll want to dereference each of the OIDs and return a list of objects. Everything that uses import will have to be modified, unless you change the name of the method and provide a wrapper method with the existing signature. Note that for Zope 2.4 this code has changed a bit. Import is now done as a subtransaction rather than a transaction on the side. Shane ___ Zope-Dev maillist - [EMAIL PROTECTED] http://lists.zope.org/mailman/listinfo/zope-dev ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope )
Re: [Zope-dev] Question about import code
Hi Shane, You wrote: Importing multiple objects simultaneously could result in a fair amount of confusion... Can you elaborate? When you import a folder, for example, it imports the folder and all objects in it. Why is it any different to import two unrelated objects? Would it be better to do this in two separate transactions? Or two subtransactions? But if you really think it's a good idea, if you used a list called return_oids instead, and appended to this list in the code above, you'd probably get what you're looking for. I tried this approach, too, and I get a ConflictError. (I can send the code and traceback if you're interested.) Note that for Zope 2.4 this code has changed a bit. Import is now done as a subtransaction rather than a transaction on the side. Thanks for the heads up. When you say subtransaction, a subtransaction of what? I'm familiar with subtransactions being atomic parts of a larger transaction. I'm not sure what this larger transaction would be in this case. If I start an import, does that start a transaction with each object's import being a subtransaction of the whole thing? (If that's the case, then I don't understand why importing several objects at once would be confusing.) Is there any documentation on how to export from and import to the ZODB? The code I'm wading through has a lot of extraneous stuff thrown in. I'd like to be able to just try exporting and importing objects from a simple Python script so I understand what's going on. Thanks, Fred -- Fred Wilson Horch mailto:[EMAIL PROTECTED] Executive Director, EcoAccess http://ecoaccess.org/ P.O. Box 2823, Durham, NC 27715-2823phone: 919.419-8567 ___ Zope-Dev maillist - [EMAIL PROTECTED] http://lists.zope.org/mailman/listinfo/zope-dev ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope )
Re: [Zope-dev] Question about import code
Fred Wilson Horch wrote: You wrote: Importing multiple objects simultaneously could result in a fair amount of confusion... Can you elaborate? When you import a folder, for example, it imports the folder and all objects in it. If there are some objects in the folder that have conflicting names and others that don't, what do you do? Also, if you're thinking about providing this functionality, what about spanning multiple folders? What if some folders already exist? The capability could change user expectations, you see, and you may need to deal with them. But that's just advice and you can freely ignore it. :-) Thanks for the heads up. When you say subtransaction, a subtransaction of what? I'm familiar with subtransactions being atomic parts of a larger transaction. I'm not sure what this larger transaction would be in this case. If I start an import, does that start a transaction with each object's import being a subtransaction of the whole thing? That's right. Is there any documentation on how to export from and import to the ZODB? Perhaps. Look at the interfaces Wiki. The code I'm wading through has a lot of extraneous stuff thrown in. I'd like to be able to just try exporting and importing objects from a simple Python script so I understand what's going on. An external method could do it. Look at what _getCopy() does in OFS/CopySupport.py. Shane ___ Zope-Dev maillist - [EMAIL PROTECTED] http://lists.zope.org/mailman/listinfo/zope-dev ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope )
