У меня есть код ниже для моего Python задания по программированию на курсе Coursera - 'Python для всех':
В этом задании я должен загрузить некоторые из список рассылки данных от http://mbox.dr-chuck.net/ и запустить процесс очистки / моделирования данных.
import sqlite3
import time
import re
import zlib
from datetime import datetime, timedelta
# Not all systems have this
try:
import dateutil.parser as parser
except:
pass
dnsmapping = dict()
mapping = dict()
def fixsender(sender,allsenders=None) :
global dnsmapping
global mapping
if sender is None : return None
sender = sender.strip().lower()
sender = sender.replace('<','').replace('>','')
# Check if we have a hacked gmane.org from address
if allsenders is not None and sender.endswith('gmane.org') :
pieces = sender.split('-')
realsender = None
for s in allsenders:
if s.startswith(pieces[0]) :
realsender = sender
sender = s
# print(realsender, sender)
break
if realsender is None :
for s in mapping:
if s.startswith(pieces[0]) :
realsender = sender
sender = mapping[s]
# print(realsender, sender)
break
if realsender is None : sender = pieces[0]
mpieces = sender.split("@")
if len(mpieces) != 2 : return sender
dns = mpieces[1]
x = dns
pieces = dns.split(".")
if dns.endswith(".edu") or dns.endswith(".com") or dns.endswith(".org") or dns.endswith(".net") :
dns = ".".join(pieces[-2:])
else:
dns = ".".join(pieces[-3:])
# if dns != x : print(x,dns)
# if dns != dnsmapping.get(dns,dns) : print(dns,dnsmapping.get(dns,dns))
dns = dnsmapping.get(dns,dns)
return mpieces[0] + '@' + dns
def parsemaildate(md) :
# See if we have dateutil
try:
pdate = parser.parse(tdate)
test_at = pdate.isoformat()
return test_at
except:
pass
# Non-dateutil version - we try our best
pieces = md.split()
notz = " ".join(pieces[:4]).strip()
# Try a bunch of format variations - strptime() is *lame*
dnotz = None
for form in [ '%d %b %Y %H:%M:%S', '%d %b %Y %H:%M:%S',
'%d %b %Y %H:%M', '%d %b %Y %H:%M', '%d %b %y %H:%M:%S',
'%d %b %y %H:%M:%S', '%d %b %y %H:%M', '%d %b %y %H:%M' ] :
try:
dnotz = datetime.strptime(notz, form)
break
except:
continue
if dnotz is None :
# print('Bad Date:',md)
return None
iso = dnotz.isoformat()
tz = "+0000"
try:
tz = pieces[4]
ival = int(tz) # Only want numeric timezone values
if tz == '-0000' : tz = '+0000'
tzh = tz[:3]
tzm = tz[3:]
tz = tzh+":"+tzm
except:
pass
return iso+tz
# Parse out the info...
def parseheader(hdr, allsenders=None):
if hdr is None or len(hdr) < 1 : return None
sender = None
x = re.findall('\nFrom: .* <(\S+@\S+)>\n', hdr)
if len(x) >= 1 :
sender = x[0]
else:
x = re.findall('\nFrom: (\S+@\S+)\n', hdr)
if len(x) >= 1 :
sender = x[0]
# normalize the domain name of Email addresses
sender = fixsender(sender, allsenders)
date = None
y = re.findall('\nDate: .*, (.*)\n', hdr)
sent_at = None
if len(y) >= 1 :
tdate = y[0]
tdate = tdate[:26]
try:
sent_at = parsemaildate(tdate)
except Exception as e:
# print('Date ignored ',tdate, e)
return None
subject = None
z = re.findall('\nSubject: (.*)\n', hdr)
if len(z) >= 1 : subject = z[0].strip().lower()
guid = None
z = re.findall('\nMessage-ID: (.*)\n', hdr)
if len(z) >= 1 : guid = z[0].strip().lower()
if sender is None or sent_at is None or subject is None or guid is None :
return None
return (guid, sender, subject, sent_at)
conn = sqlite3.connect('index.sqlite')
cur = conn.cursor()
cur.execute('''DROP TABLE IF EXISTS Messages ''')
cur.execute('''DROP TABLE IF EXISTS Senders ''')
cur.execute('''DROP TABLE IF EXISTS Subjects ''')
cur.execute('''DROP TABLE IF EXISTS Replies ''')
cur.execute('''CREATE TABLE IF NOT EXISTS Messages
(id INTEGER PRIMARY KEY, guid TEXT UNIQUE, sent_at INTEGER,
sender_id INTEGER, subject_id INTEGER,
headers BLOB, body BLOB)''')
cur.execute('''CREATE TABLE IF NOT EXISTS Senders
(id INTEGER PRIMARY KEY, sender TEXT UNIQUE)''')
cur.execute('''CREATE TABLE IF NOT EXISTS Subjects
(id INTEGER PRIMARY KEY, subject TEXT UNIQUE)''')
cur.execute('''CREATE TABLE IF NOT EXISTS Replies
(from_id INTEGER, to_id INTEGER)''')
conn_1 = sqlite3.connect('mapping.sqlite')
cur_1 = conn_1.cursor()
cur_1.execute('''SELECT old,new FROM DNSMapping''')
for message_row in cur_1 :
dnsmapping[message_row[0].strip().lower()] = message_row[1].strip().lower()
mapping = dict()
cur_1.execute('''SELECT old,new FROM Mapping''')
for message_row in cur_1 :
old = fixsender(message_row[0])
new = fixsender(message_row[1])
mapping[old] = fixsender(new)
# Done with mapping.sqlite
conn_1.close()
# Open the main content (Read only)
conn_1 = sqlite3.connect('file:content.sqlite?mode=ro', uri=True)
cur_1 = conn_1.cursor()
allsenders = list()
cur_1.execute('''SELECT email FROM Messages''')
for message_row in cur_1 :
sender = fixsender(message_row[0])
if sender is None : continue
if 'gmane.org' in sender : continue
if sender in allsenders: continue
allsenders.append(sender)
print("Loaded allsenders",len(allsenders),"and mapping",len(mapping),"dns mapping",len(dnsmapping))
cur_1.execute('''SELECT headers, body, sent_at
FROM Messages ORDER BY sent_at''')
senders = dict()
subjects = dict()
guids = dict()
count = 0
for message_row in cur_1 :
hdr = message_row[0]
parsed = parseheader(hdr, allsenders)
if parsed is None: continue
(guid, sender, subject, sent_at) = parsed
# Apply the sender mapping
sender = mapping.get(sender,sender)
count = count + 1
if count % 250 == 1 : print(count,sent_at, sender)
# print(guid, sender, subject, sent_at)
if 'gmane.org' in sender:
print("Error in sender ===", sender)
sender_id = senders.get(sender,None)
subject_id = subjects.get(subject,None)
guid_id = guids.get(guid,None)
if sender_id is None :
cur.execute('INSERT OR IGNORE INTO Senders (sender) VALUES ( ? )', ( sender, ) )
conn.commit()
cur.execute('SELECT id FROM Senders WHERE sender=? LIMIT 1', ( sender, ))
try:
row = cur.fetchone()
sender_id = row[0]
senders[sender] = sender_id
except:
print('Could not retrieve sender id',sender)
break
if subject_id is None :
cur.execute('INSERT OR IGNORE INTO Subjects (subject) VALUES ( ? )', ( subject, ) )
conn.commit()
cur.execute('SELECT id FROM Subjects WHERE subject=? LIMIT 1', ( subject, ))
try:
row = cur.fetchone()
subject_id = row[0]
subjects[subject] = subject_id
except:
print('Could not retrieve subject id',subject)
break
# print(sender_id, subject_id)
cur.execute('INSERT OR IGNORE INTO Messages (guid,sender_id,subject_id,sent_at,headers,body) VALUES ( ?,?,?,datetime(?),?,? )',
( guid, sender_id, subject_id, sent_at,
zlib.compress(message_row[0].encode()), zlib.compress(message_row[1].encode())) )
conn.commit()
cur.execute('SELECT id FROM Messages WHERE guid=? LIMIT 1', ( guid, ))
try:
row = cur.fetchone()
message_id = row[0]
guids[guid] = message_id
except:
print('Could not retrieve guid id',guid)
break
cur.close()
cur_1.close()
Тем не менее, я получаю сообщение об ошибке:
Traceback (последний вызов был последним): файл "", строка 161, в sqlite3.OperationalError: нет такой таблицы: DNSMapping
Кто-нибудь сможет мне помочь, почему я получаю эту ошибку?