Cacheing class object / sqlite3
Python and SQL databases example from a Well House Consultants training course
More on Python and SQL databases [link]
Source code: kvcache.py Module: Y113
# Cacheing class object / sqlite3
class kvcache (object):
def __init__(self,remote_url,ttl = 20,localfile = "/tmp/mycache"):
self.remote = remote_url
self.ttl = ttl
self.localfile = localfile
request = self.remote.replace("*",key,1)
conn = sqlite3.connect(self.localfile)
c = conn.cursor()
status = "cached"
c.execute('SELECT * FROM savings WHERE key = "' + request + '"')
record = c.fetchone()
c.execute('CREATE TABLE savings (key text, value text, tstamp int)')
status = "created database"
record = 
neednew = 1
stuff = record
age = time.time() - record
if age < self.ttl:
neednew = 0
c.execute('DELETE FROM savings WHERE key = "' + request + '"')
response = urllib2.urlopen(request)
stuff = response.read()
status = "fresh read"
whengot = int(time.time())
c.execute ('INSERT INTO savings VALUES (?, ?, ?)', (request, stuff, whengot))
self.latest_source = status
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