On Mar 7, 10:58 pm, odeits <ode...@gmail.com> wrote:
> On Mar 7, 1:07 pm, Scott David Daniels <scott.dani...@acm.org> wrote:
>
>
>
> > odeits wrote:
> > > I am looking to clean up this code... any help is much appreciated.
> > > Note: It works just fine, I just think it could be done cleaner.
>
> > > The result is a stack of dictionaries. the query returns up to
> > > STACK_SIZE ads for a user. The check which i think is very ugly is
> > > putting another contraint saying that all of the ni have to be the
> > > same.
>
> > Well, the obvious way to get your constraint is by changing your SQL,
> > but if you are going to do it by fetching rows, try:
>
> > FIELDS = 'ni adid rundateid rundate city state status'.split()
> > ni = UNSET = object() # use None unless None might be the value
> > stack = []
> > rows = self.con.execute(adquerystring, (user,STACK_SIZE)).fetchall()
> > for row in rows:
> > ad = dict()
> > for field in FIELDS:
> > ad[field] = row[field]
> > for field in 'city', 'state':
> > if ad[field] is None:
> > ad[field] = 'None'
> > if ni != ad['ni']:
> > if ni is UNSET:
> > ni = ad['ni']
> > else:
> > break
> > stack.append(ad)
>
> > --Scott David Daniels
> > scott.dani...@acm.org
>
> Taking from several suggestions this is what i have come up with for
> now:
>
> for row in ifilter(lambda r: r['ni'] == rows[0]['ni'],rows):
> ad = dict()
>
> keys = row.keys() # if python 2.6
> keys =
> ['ni','adid','rundateid','rundate','city','state','status'] # if
> python 2.5
>
> for index in row.keys():
> if row[index] is None:
> ad[index] = 'None'
> else:
> ad[index] = row[index]
> stack.append(ad)
> print row
>
> the test to see if the ad is valid is placed in the ifilter so that I
> dont build the dictionary unnecessarily. and the None special case is
> fairly simple to read now. The None case would even be irrelevant if i
> could get the damn xmlrpc to allow null. sigh. anyhow. thanks for all
> of your input, it is definitely better than it was ;)
For those of you who asked about the SQL the full function is here.
The connection is to a sqlite database with the row_factory set to
sqlite.Row
def get(self,user):
'''
Fetches an ad for USER, assigns the ad and returns a
dictionary that represents an ad
'''
stack = []
aduserquerystring = "SELECT ni, adid, rundateid, rundate,
city, state, status, priority,time FROM ads NATURAL JOIN rundates
NATURAL JOIN newspapers WHERE ( status in (1,3) and user = ?) "
expiredadquerystring = "SELECT ni, adid, rundateid, rundate,
city, state, status, priority,time FROM ads NATURAL JOIN rundates
NATURAL JOIN newspapers WHERE ( status = 1 AND time < DATETIME
('NOW', '-%d MINUTES') ) LIMIT 0,?"%(MINUTES_TO_EXPIRE,)
adquerystring = "SELECT ni, adid, rundateid, rundate, city,
state, status , priority, time FROM ads NATURAL JOIN rundates NATURAL
JOIN newspapers WHERE (status IN (0,2) AND priority IN ( SELECT
priority FROM users NATURAL JOIN groups WHERE user = ? )) ORDER BY
status DESC, priority ASC, ni ASC, time ASC, adid ASC LIMIT 0,?"
rows = self.con.execute(aduserquerystring,(user,)).fetchall()
if len(rows) == 0:
rows = self.con.execute(expiredadquerystring,
(STACK_SIZE,)).fetchall()
if len(rows) == 0:
rows = self.con.execute(adquerystring,
(user,STACK_SIZE)).fetchall()
print user
keys =
['ni','adid','rundateid','rundate','status','city','state']
for row in ifilter(lambda r: r['ni'] == rows[0]['ni'], rows):
ad = dict( )
for key in keys:
if row[key] is None:
ad[key] = 'None'
else:
ad[key] = row[key]
stack.append(ad)
print row
self.con.executemany('UPDATE ads SET user = ?, status = CASE
(status) WHEN 1 THEN 1 WHEN 0 THEN 1 WHEN 2 THEN 3 END WHERE adid = ?',
[(user, ad['adid']) for ad in stack])
self.con.commit()
return stack
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