Also, now when I ran the following code in the console:
========================================
from google.appengine.ext import db
key_of_specific_Thumb_entity = "agdhcHRydXNochALEgpJbWFnZVRodW1iGEUM"
<<==key grabbed from datastore for thumbnail (which is a parent of the
Bin/Large Image)
db.get(db.Key(key_of_specific_Thumb_entity))
I get this error:
============
Traceback (most recent call last):
File "C:\Program Files\Google\google_appengine\google\appengine\ext
\admin\__init__.py", line 194, in post
exec(compiled_code, globals())
File "<string>", line 5, in <module>
File "C:\Program Files\Google\google_appengine\google\appengine\ext
\db\__init__.py", line 1053, in get
cls1 = class_for_kind(entity.kind())
File "C:\Program Files\Google\google_appengine\google\appengine\ext
\db\__init__.py", line 217, in class_for_kind
raise KindError('No implementation for kind \'%s\'' % kind)
KindError: No implementation for kind 'ImageThumb'
I'm guessing it has something to do with it being a parent or
something!?
On Mar 16, 1:03 pm, iceanfire <iceanf...@gmail.com> wrote:
> Hi,
>
> I'm having a bit of trouble understanding how to use parents/children
> properties within transactions.
>
> I have divided up my "Thumbnails" and the actual "Large Image" into
> two separate models to save processing power, but when I upload, I
> want to make sure that both entities are updated--therefore I have to
> use transactions.
>
> Short version (incase the answer is something simple):
> ==========================================
> Can I query to find out the children entities of a Parent entity?
>
> Long Version:
> ===========
> Key fact - thumbnails is connected to the Large Image (bin) via the
> column "bin_id"
>
> The code in Exhibit 1 doesn't work because I get the 'error
> "ImageThumb" must have a complete key before it can be used as a
> parent'. So I tried to:
> 1. .put() ImageThumb
> 2. assign it as a parent
> 3. .put() Bin (the large image)
> 4. get the ID from step 3
> 5. insert the id in the ImageThumb and .put() it again.
>
> I got the error: you can't put an entity more than once in appengine!
>
> So my last resort was to just get rid of binID and do steps 1-3. This
> works! But now i'm stuck as to getting the Large Image (child) for a
> specific thumbnail(parent).
>
> Code Exhibit 1
> ======================
> def uploadImages(self):
> thumb_db = ImageThumb()
> thumb = images.resize(image_data,
> 150,150,images.JPEG)
> thumb_db.thumb = db.Blob(thumb)
>
> bin_db = ImageBin(parent=thumb_db)
> bin_db.image = image_data
> bin_put=bin_db.put()
> bin_id = bin_put.id()
>
> thumb_db.binId = bin_id <<=== need binId so
> that thumbnail is linked to actual image (so I can use get by id
> class)
>
> thumb_db.type= "Picture"
> thumb_put = thumb_db.put()
> thumb_id = thumb_put.id()
--~--~---------~--~----~------------~-------~--~----~
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.com
For more options, visit this group at
http://groups.google.com/group/google-appengine?hl=en
-~----------~----~----~----~------~----~------~--~---
