Hi,
In GAE it's possibe to supply a "key_name" when you insert an entity. This
is a string that you can then use as an id to efficiently fetch an entity
from db.
(
https://developers.google.com/appengine/docs/python/datastore/entities#Python_Kinds_and_identifiers
)
I would like to be able to do this using web2py. I could also choose to use
the GAE API directly to do this but then a could not make use thing like
calculated Fields etc in my web2py tables.
I made the following modification to the GoogleDatastoreAdapter insert()
function:
def insert(self,table,fields):
dfields=dict((f.name,self.represent(v,f.type)) for f,v in fields)
# table._db['_lastsql'] = self._insert(table,fields)
# Field name 'gae_key_name' can be used insert using key_name for
both DB and NDB.
keyname = None
*if 'gae_key_name' in dfields: keyname =
dfields['gae_key_name'] if self.use_ndb:
dfields['id'] = dfields.pop('gae_key_name') else:
dfields['key_name'] = dfields.pop('gae_key_name')*
tmp = table._tableobj(**dfields)
tmp.put()
key = tmp.key if self.use_ndb else tmp.key()
rid = Reference(key.id())
(rid._table, rid._record, rid._gaekey) = (table, None, key)
return rid
Now one can insert using a field name 'gae_key_name'.
DB and NDB expect different parameter names for the model constructors to
supply a key_name. 'key_name vs 'id''.
Now the only problem is that _listify() in Table required that all fields
are defined in the Table.
We can now choose to define a Field "gae_key_name" in every Table that we
want to use this feature for.
Another option is to modify the _listify function a bit to accomodate this:
def _listify(self,fields,update=False):
new_fields = {} # format: new_fields[name] = (field,value)
# store all fields passed as input in new_fields
# 'gae_key_name' is GAE specific and should not be defined in the
table.
for name in fields:
if not name in self.fields:
*if name not in ['id', 'gae_key_name']: raise
SyntaxError( 'Field %s does not belong to the table'
% name) if name == 'gae_key_name': #
Create stub Field for 'gae_key_name' so it can be included
# without being defined in the model. field =
Field('gae_key_name', 'string')
new_fields['gae_key_name'] = field, fields['gae_key_name']*
else:
field = self[name]
value = fields[name]
if field.filter_in:
value = field.filter_in(value)
new_fields[name] = (field,value)
The last option feels a bit hacky but removes the requirement to define a
Field 'gae_key_name' in every Table.
What to you think?
I attached a patch that includes both changes.
Regards,
Quint
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Index: E:/repositories/Mercurial/web2py/gluon/dal.py
===================================================================
--- E:/repositories/Mercurial/web2py/gluon/dal.py (revision 5706:f691e2676f64)
+++ E:/repositories/Mercurial/web2py/gluon/dal.py (revision 5706+:f691e2676f64+)
@@ -5300,6 +5300,15 @@
def insert(self,table,fields):
dfields=dict((f.name,self.represent(v,f.type)) for f,v in fields)
# table._db['_lastsql'] = self._insert(table,fields)
+ # Field name 'gae_key_name' can be used insert using key_name for both DB and NDB.
+ keyname = None
+ if 'gae_key_name' in dfields:
+ keyname = dfields['gae_key_name']
+ if self.use_ndb:
+ dfields['id'] = dfields.pop('gae_key_name')
+ else:
+ dfields['key_name'] = dfields.pop('gae_key_name')
+
tmp = table._tableobj(**dfields)
tmp.put()
key = tmp.key if self.use_ndb else tmp.key()
@@ -9035,11 +9044,17 @@
new_fields = {} # format: new_fields[name] = (field,value)
# store all fields passed as input in new_fields
+ # 'gae_key_name' is GAE specific and should not be defined in the table.
for name in fields:
if not name in self.fields:
- if name != 'id':
+ if name not in ['id', 'gae_key_name']:
raise SyntaxError(
'Field %s does not belong to the table' % name)
+ if name == 'gae_key_name':
+ # Create stub Field for 'gae_key_name' so it can be included
+ # without being defined in the model.
+ field = Field('gae_key_name', 'string')
+ new_fields['gae_key_name'] = field, fields['gae_key_name']
else:
field = self[name]
value = fields[name]
