Re: [google-appengine] Re: Running some code immediately before a Datastore put()?
I also found Nick Johnson's (google guy) post on this to be very useful. Honestly, his whole blog is useful - App Engine tips from a guy on the inside. http://blog.notdot.net/2009/9/Custom-Datastore-Properties-1-DerivedProperty -- You received this message because you are subscribed to the Google Groups Google App Engine group. To view this discussion on the web visit https://groups.google.com/d/msg/google-appengine/-/Si2ySLfz_noJ. To post to this group, send email to google-appengine@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
[google-appengine] Re: Running some code immediately before a Datastore put()?
Nick, I've been faced with your exact situation. I have to say I don't understand PreCallHook, and maybe that would be the best approach, but here's what I do know. Overriding put is a bad idea, and as you point out, the override will not be called in a batch put. I found that the most elegant solution was to derive a new type of db.Property, and override its get_value_for_datastore. Then GAE will automatically do what you want regardless of how the entity is being put. On Jan 14, 1:51 am, Eric Ka Ka Ng ngk...@gmail.com wrote: would a PreCallHook works for your case? http://code.google.com/appengine/articles/hooks.html - eric 2010/1/14 Nickolas Daskalou n...@daskalou.com: I have a property of a Model that is a hash of another property of the same Model, eg: class MyModel(db.Model): something = db.StringProperty() something_hash = db.StringProperty() def generate_hash(self): self.something_hash = sha1(self.something) I want generate_hash() to be automatically called just before the entity is put() into the Datastore, without the developer having to explicitly call entity.generate_hash(). I know I can create a put() method that makes such a call and then calls put() on the superclass, but (a) is that the best way to do it, and (b) if the put() is part of a batch put (eg. via db.put(entities)), will the put() method of each model instance still be called? Nick -- You received this message because you are subscribed to the Google Groups Google App Engine group. To post to this group, send email to google-appeng...@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en. -- You received this message because you are subscribed to the Google Groups Google App Engine group. To post to this group, send email to google-appeng...@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
Re: [google-appengine] Re: Running some code immediately before a Datastore put()?
Thanks guys, both great suggestions. I'll try and get PreCallHook working because that would allow me to add a pre_put() method to my Models, and then using these PreCallHooks I can call pre_put() for each of the entities being put into the Datastore. Failing that, I'll create a new derived property for my Model and do as Devel63 said. 2010/1/15 Devel63 danstic...@gmail.com Nick, I've been faced with your exact situation. I have to say I don't understand PreCallHook, and maybe that would be the best approach, but here's what I do know. Overriding put is a bad idea, and as you point out, the override will not be called in a batch put. I found that the most elegant solution was to derive a new type of db.Property, and override its get_value_for_datastore. Then GAE will automatically do what you want regardless of how the entity is being put. On Jan 14, 1:51 am, Eric Ka Ka Ng ngk...@gmail.com wrote: would a PreCallHook works for your case? http://code.google.com/appengine/articles/hooks.html - eric 2010/1/14 Nickolas Daskalou n...@daskalou.com: I have a property of a Model that is a hash of another property of the same Model, eg: class MyModel(db.Model): something = db.StringProperty() something_hash = db.StringProperty() def generate_hash(self): self.something_hash = sha1(self.something) I want generate_hash() to be automatically called just before the entity is put() into the Datastore, without the developer having to explicitly call entity.generate_hash(). I know I can create a put() method that makes such a call and then calls put() on the superclass, but (a) is that the best way to do it, and (b) if the put() is part of a batch put (eg. via db.put(entities)), will the put() method of each model instance still be called? Nick -- You received this message because you are subscribed to the Google Groups Google App Engine group. To post to this group, send email to google-appengine@googlegroups.com . To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.comgoogle-appengine%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en. -- You received this message because you are subscribed to the Google Groups Google App Engine group. To post to this group, send email to google-appeng...@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.comgoogle-appengine%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en. -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to google-appeng...@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
Re: [google-appengine] Re: Running some code immediately before a Datastore put()?
I'm pretty sure the code on the GAE Hooks article ( http://code.google.com/appengine/articles/hooks.html) is wrong. 4th code snippet, shouldn't the very first line: def path_appengine(): be moved to the bottom, just above this line: apiproxy_stub_map.apiproxy.GetPreCallHooks().Append() ? 2010/1/15 Nickolas Daskalou n...@daskalou.com Thanks guys, both great suggestions. I'll try and get PreCallHook working because that would allow me to add a pre_put() method to my Models, and then using these PreCallHooks I can call pre_put() for each of the entities being put into the Datastore. Failing that, I'll create a new derived property for my Model and do as Devel63 said. 2010/1/15 Devel63 danstic...@gmail.com Nick, I've been faced with your exact situation. I have to say I don't understand PreCallHook, and maybe that would be the best approach, but here's what I do know. Overriding put is a bad idea, and as you point out, the override will not be called in a batch put. I found that the most elegant solution was to derive a new type of db.Property, and override its get_value_for_datastore. Then GAE will automatically do what you want regardless of how the entity is being put. On Jan 14, 1:51 am, Eric Ka Ka Ng ngk...@gmail.com wrote: would a PreCallHook works for your case? http://code.google.com/appengine/articles/hooks.html - eric 2010/1/14 Nickolas Daskalou n...@daskalou.com: I have a property of a Model that is a hash of another property of the same Model, eg: class MyModel(db.Model): something = db.StringProperty() something_hash = db.StringProperty() def generate_hash(self): self.something_hash = sha1(self.something) I want generate_hash() to be automatically called just before the entity is put() into the Datastore, without the developer having to explicitly call entity.generate_hash(). I know I can create a put() method that makes such a call and then calls put() on the superclass, but (a) is that the best way to do it, and (b) if the put() is part of a batch put (eg. via db.put(entities)), will the put() method of each model instance still be called? Nick -- You received this message because you are subscribed to the Google Groups Google App Engine group. To post to this group, send email to google-appeng...@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.comgoogle-appengine%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en. -- You received this message because you are subscribed to the Google Groups Google App Engine group. To post to this group, send email to google-appeng...@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.comgoogle-appengine%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en. -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to google-appeng...@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
Re: [google-appengine] Re: Running some code immediately before a Datastore put()?
You can use aetycoon, example: http://blog.notdot.net/2009/12/Most-popular-metrics-in-App-Engine 2010/1/15 Nickolas Daskalou n...@daskalou.com: I'm pretty sure the code on the GAE Hooks article (http://code.google.com/appengine/articles/hooks.html) is wrong. 4th code snippet, shouldn't the very first line: def path_appengine(): be moved to the bottom, just above this line: apiproxy_stub_map.apiproxy.GetPreCallHooks().Append() ? 2010/1/15 Nickolas Daskalou n...@daskalou.com Thanks guys, both great suggestions. I'll try and get PreCallHook working because that would allow me to add a pre_put() method to my Models, and then using these PreCallHooks I can call pre_put() for each of the entities being put into the Datastore. Failing that, I'll create a new derived property for my Model and do as Devel63 said. 2010/1/15 Devel63 danstic...@gmail.com Nick, I've been faced with your exact situation. I have to say I don't understand PreCallHook, and maybe that would be the best approach, but here's what I do know. Overriding put is a bad idea, and as you point out, the override will not be called in a batch put. I found that the most elegant solution was to derive a new type of db.Property, and override its get_value_for_datastore. Then GAE will automatically do what you want regardless of how the entity is being put. On Jan 14, 1:51 am, Eric Ka Ka Ng ngk...@gmail.com wrote: would a PreCallHook works for your case? http://code.google.com/appengine/articles/hooks.html - eric 2010/1/14 Nickolas Daskalou n...@daskalou.com: I have a property of a Model that is a hash of another property of the same Model, eg: class MyModel(db.Model): something = db.StringProperty() something_hash = db.StringProperty() def generate_hash(self): self.something_hash = sha1(self.something) I want generate_hash() to be automatically called just before the entity is put() into the Datastore, without the developer having to explicitly call entity.generate_hash(). I know I can create a put() method that makes such a call and then calls put() on the superclass, but (a) is that the best way to do it, and (b) if the put() is part of a batch put (eg. via db.put(entities)), will the put() method of each model instance still be called? Nick -- You received this message because you are subscribed to the Google Groups Google App Engine group. To post to this group, send email to google-appeng...@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en. -- You received this message because you are subscribed to the Google Groups Google App Engine group. To post to this group, send email to google-appeng...@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en. -- You received this message because you are subscribed to the Google Groups Google App Engine group. To post to this group, send email to google-appeng...@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en. -- You received this message because you are subscribed to the Google Groups Google App Engine group. To post to this group, send email to google-appeng...@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
