Develop Reference

Benchmarking cache dictionary leads to "Unexpected EOF while reading bytes"

I have Clickhouse version 20.8.3.18 and python3 installed on a vm stress testing Cache dictionaries. After a certain number of entries the query using clickhouse_driver, I'll get the error
Unexpected EOF while reading bytes
Is this an error due to the driver/python related or due to the cache being maxed on the system. For example this happens on a file size 203 columns and 10000 rows on a machine with 32Gb of RAM and 256Gb of SSD memory, a csv file of around 66Mb which seems quite small for such an error. The query I'm running is:
SELECT
dictGet('CacheDictionary', 'date', toUInt64(number)) AS date,
SUM(dictGet('CacheDictionary', 'filterColumn', toUInt64(number))) AS val,
AVG(dictGet('CacheDictionary', 'filterColumn', toUInt64(number))) AS avg
FROM numbers(1, 10000)
GROUP BY date
An example entry of the csv file is:
20000,2021-02-05,6867,0.5314826651111791,OA9SMRN54LC3MTDW,D6S8AYXZ3JVSHPCY,12UQV1JR87MT00EP,3WBT23MA2QN6URA7,YGKJR5577BP6S3AD,2T90WPW1REOZA0L9,JQG8Z6FXXIX2788M,OAOVV1YX3A6HKQV8,FISBMOAHEXHAAKEY,XAULW5F90T3VEMUL,RAAZ5TM5XL7GRC1F,B16JEGDHXUXFI2R9,DETSZ7BR45CRAIA7,Z2X53PAQYCSBHPU3,SRISC0ZLWXC2DP34,KO2M3044JX5JCB74,ML776REFIX3Z1L78,ND6PXBOR135SWFSB,ZF4K45N2AIGFAK0L,RFE3EHCKC5EPYE2V,NJKM5T8UUD5NRDPX,O57IQW0670LP00I9,F0EBZ3BXHPETCFSY,RUZ7VH2IM0DIZ4UC,08BP467WG7ROEHTJ,9LSTNLUA240T2K4D,5L4PIRKMK746QW5Q,2VX3SER8ULU93NZG,Z0MZ9C3TTPR6WFDV,KB32XWCR67AWGSIB,PDM8QJ34X4EOTVN1,P7TUVP8Q1YF9S746,YDFDBCG6S2EXYPNW,55RN0F4UMGF3ABQZ,RRF895J8LQSLI48U,54OQWCJODIEQLRQF,D5ZJPGAG7CCO4LWA,UQDWEXPI184UUJQD,3QF6QAS32ITRL8JH,FPQ324RO04LNVAMO,ZJ6QCWNQCBQOE7F5,6OWVEVWHNSZILC6E,GIUD29OIFF3LUCCX,VGBJHKW32BUNUSDH,908TDRODVZIIC5O8,UCIU38BXEREJMO4M,5LKJ23ER4CKUZ88J,A1GBKPPM10L8X5RM,BB3SAVWF3CNBDXHO,279MIC1OXTDS2PFP,J6UVFJE8RGFK4LDN,3CE12GT27GX0WVWU,PNNTRLDFVJQ0TCRK,MI7XOHWUQX3W938H,LKZPV4K0BA6OE3R0,YJMLI82UBLSZWP7U,JORNKD1MSVECXBRF,CO5KKJIL1FHEYA11,GXVXWDOI538WCLC0,OPODB2R2ITSX0E6J,3VE7SOJZL3DKIES7,5LPXB17GJ94S86HL,UQ0DZVUDMBD39LC3,KSSVOBUKMZC7T89M,P6YL0WW22NOM5A36,RA46SZF4ZLO5YWUM,TUTMJ34X4040USXX,09HPKJAD58P3FVMP,DM0NJVFYKR2653HH,HP869NM4Y2EBE3ND,RVKP40RPBOPB6RPQ,WI3QXYA5XIWJUFUK,770L6U5KAEPKKJC1,2H0XNUDM41QBAZWB,8AWJ2Y7RB9F2WTT0,Y6T3PIPLU3FCBZCU,CY8SCO15RNUWQU2B,DRC88XH21J9ADT6Z,MLZ2JN7F8MXVBHBI,2YSUVHRL4V0EVHXF,Y0U12EBQSEVE6W6X,A6RRJY191S0JOXJH,4F12P4K0SJ6EDKSD,THCRJ2ZEXGM1RUM4,PF0OUAULUNIW0W9X,EK1249WXC0C2KKY8,11WEDAAJL7BL4T4U,4K8OP1WXSN1MIXPF,8D0WNN1672A6WK07,5RLYH7K00ZSR1LL2,EKEXBG87U1X6UOLL,YWK3V1F7MTAF9T19,XZ8ZF0XO5V8TCBPS,A3RX8X8A8I11Z8X3,77P2Q5WRSTL4ERAI,00BGNPDYFSVG5F81,5KTUM76C42VTP4I7,TA933GZZN8OQ20QJ,612WNQ74RDHMBWX3,D41HNOBPX11GFYWO,OGR4A0EPCSS00XL6,QIOH165Y5JGKJMFC,TF2R9TFC5TJN2PER,TYNXWI46H7I83O77,JMD5DOEV4U628SDK,D7ECJH43FEC77UCJ,FKA9AT5J20QI3MQP,7QSU0I8VRRLUMD7R,6OJ1O2XI2QJXP6W2,UD2QVJXNUFRCAO43,GS3TZUW8U6Z8EWWQ,QD79GBSO6D6GCAZ1,GQ5TUY2FMJSNMTRK,OGOYL2PD64E2DOOQ,Q733OU5P7J7SAFS1,GBS7MV5QOMQ4E89N,SB8MIQ1P37HMQZBJ,Z6G96BM7FL4150H3,05PS81HW528971RM,6F3KFLYT0345GI43,G65CDWEORNH3OUCY,12F43L99AZ84PDWR,GQQVWMTMS471WAWD,F1DFWRJ1F9M9MUTT,1M734H07IQAW49Q3,OPSRG5J7370227XE,BIPNR22KFF71MKQN,PV7DWGCQF5551FKT,YPGQVGUP37MRJY2B,RILKP96QV69WBW2D,4RXDCJURAVCQEGLX,XGIPC0AK1K0I6KDP,HMSE306L5NAK62LC,YAZHMS2UHGMWIB44,RZCAVUM45YTNV23T,3B7K07XPRTE8OMW1,FTP48ED5DQ4K3DM8,WW419RRJ2WU1F15L,85FWD49J0ARSUGI9,4U4768ANPCJ46K5P,EJ24BNUA6OZMUDEL,6Z27W6BN36GO8QWU,5AMZ4UU819GSI454,KMNIEJ2V5PI83KGP,APT4CYG8M5FM0BSW,IME5VRP08W468DZE,6BT4W0ZAW6C7993L,DRD6Q4P8BZVDG37U,2R1OEWQFV5J597AF,CKS41A6PXKVYICAG,OQYZ9UOQRVS3LLTF,JA3PZSAXFCJVZVLB,J23BP73T6GNC0Z08,GWOJXMXDVHCRE51Y,I826DE6KEVQK2PFC,6FF5LWM61KCM4C9K,P16P80EIX2X87OZO,O5GEOEO72CDV4GAX,UMKFUKMV6U0L5PM5,U64YI4G53LR3SC6J,CLML8KPAL697KYYJ,LMH2W0STEJ5H2J2S,AL61EP61ZR3GOPN3,Z3AEUMZSX4MQJ6M6,IS5RFEWIJ8XHYNK0,TNE1BS4JYN280PIF,67IER2YS6N2XHEW1,63P3O4X42T2INRT4,XYV043108XRK7Y4S,RW0HN600K0GQXF4Y,BZ1ZE6IBB4B72A81,QHAINYDIZX7838YI,7FFCKG3XJSZ2DIHJ,DF6C1OMPC1ETFPDZ,1EJ3EW0TXKVBC88R,WX6HG8FD021VFZ2S,W4OB9NZRODSTM96M,6GDA3L5CLBPVTPWQ,1Y4U7BL9UHPBJVIX,Y31SUUZ0JF2AXZWO,PL2I18PA0SVXG85E,TEY1HC97QMZ5YXMI,T49EVLLM43AI4OG3,0SDNMLWY85Z7NENX,4446QKGO8UL6RERT,IMEAM22I51GT4ZHY,HUCLC93NIUG0C5R0,5VPBRUUVMBXP7HJY,XCOOPM3JU5VHQ94T,3LRZGAF451G9XDIN,Y6VIN1E31NYRLA2N,RAROO2EM5Q9NJRG9,NUQ2QJ9M6T5KRCHK,WQKKQK8UBB30GRWI,20SOMMKD08FYAENW,1G9K4UFWAI8Q7Z8K,XLG898A4MQXZHVYR,FPT67A7VDLVZEWYH,6DQ6417FF07FORXZ,10RUAPY5KGAYBZZD
I've posted part of the code trying to find the maximum number of cache items stored, along with the queries executed for each. In selectBenchmark the string correspond to the query above. The parameters for each are fairly self explanatory (the xmlFile is the dictionary created in /etc/lib/clickhouse-server).
def cacheMaxItems(csvRead, xmlFile, benchmarkType, columnStepSize, rowStepSize):
maxCache = []
os.system('rm -f ' + csvRead)
os.system('bash /root/restartCH.sh')
for j in range(1, 13):
outputCSV = '/root/results' + benchmarkType + '/cacheResults' + str(j*columnStepSize) + '.csv'
with open(outputCSV, 'w') as fp:
wr = csv.writer(fp)
wr.writerow([benchmarkType + ': Number of rows', 'Loading time', 'Mean', 'Variance', 'Skewness', 'Number of Columns: ' + str(j*columnStepSize)])
for i in range(1, 10000):
if i%5 == 0:
os.system('bash /root/restartCH.sh')
createCSV(10000, j*columnStepSize, csvRead)
try:
clickhouseDictionary(rowStepSize*i*j*columnStepSize, j*columnStepSize, xmlFile, csvRead, 'Cache')
if benchmarkType == 'Random':
results = selectBenchmark(i*rowStepSize, j*columnStepSize, 'Random', 'Cache')
elif benchmarkType == 'Consecutive':
results = selectBenchmark(i*rowStepSize, j*columnStepSize, 'Consecutive', 'Cache')
elif benchmarkType == 'CPU':
results = selectBenchmark(i*rowStepSize, j*columnStepSize, 'CPU', 'Cache')
results.insert(0, i*rowStepSize)
with open(outputCSV, 'a') as fp:
wr = csv.writer(fp)
wr.writerow(results)
print('Successfully loaded and queried cache of size ' + str(rowStepSize*i*j*columnStepSize) + '.')
except Exception as ex:
print(ex)
os.system('rm -f ' + csvRead)
os.system('bash /root/restartCH.sh')
maxCache.append([j*columnStepSize, (i-1)*rowStepSize])
print(maxCache)
break
return maxCache
def selectBenchmark(numberOfRows, numberOfColumns, benchmarkType, dictType):
client = Client('localhost', port=9000, database='system')
client.execute('SYSTEM RELOAD DICTIONARY ' + dictType + 'Dictionary')
loadingTime = client.last_query.elapsed
client.execute('SELECT dictGet(\'' + dictType + 'Dictionary\', \'random0\', toUInt64(1))', query_id=str(uuid.uuid4()))
loadingTime += client.last_query.elapsed
loop = True
counter = 0
j=0
while loop:
times = []
for i in range(0, 31):
query_id = str(uuid.uuid4())
string = stringGen(numberOfRows, numberOfColumns, benchmarkType, dictType)
client.execute(string, query_id = query_id)
times.append(client.last_query.elapsed)
if max(times) > loadingTime:
loadingTime = max(times)
stats = transformedMLE(times)
redactedTimes = [x for x in times if (stats[0]-3*np.sqrt(stats[1])) < x < (stats[0]+3*np.sqrt(stats[1]))]
if len(times) - len(redactedTimes) <= 3:
loop = False
elif j > 15:
print('High variance query')
loop = False
j+=1
result = transformedMLE(redactedTimes)
loadingTime = loadingTime - result[0]
result.insert(0, loadingTime)
client.disconnect()
return result
The restartCH.sh file is
service clickhouse-server forcerestart
as the cache overflow often blocks the restart command.
There is no output to the server error logs indicating that this is a problem with the python driver, perhaps reading the large amounts of data being returned. I also get the 'Killed' python output which also points towards cache issues, which is to be expected as I'm benchmarking cache dictionaries.

Unexpected EOF while reading bytes -- it's python driver error.
Check clickhouse-server.log for real error.
20.8.3.18 is out support , please upgrade to 20.8.12.2

I was running into a similar problem on Ubuntu when starting the server binary directly using "2>&1 /dev/null &" to suppress the output from stderr and stdout to /dev/null, Python driver was throwing the error but server would still be working when connecting via the clickhouse client binary command-line. Issue was resolved by tweaking the server startup script to just redirect stderr with " 2> /dev/null &" (referring to https://www.baeldung.com/linux/silencing-bash-output difference between using 2> and 2>&1).

How to convert CIDR format to list of all possible IP addresses?[BATCH]

I would like to know how can I convert CIDR IP(s) into a list of all possible IP addresses. I know this topic already exists but none of them really gave me what I need.
So the question is really simple. If anyone could make a program[no matter what language(ruby,python or etc. etc.)] that would create a .txt file - list of IP addresses from a .txt file where are CIDR IPs.
TEXT THAT CONTAINS CIDR IPs -> PROGRAM PROCESSING -> NEW FILE "LIST OF ALL POSSIBLE IPs FROM CHOSEN FILE"
I hope I was clear enough and that you did understand me and I also hope someone will help me. Thank you very much in advance!
If CIDR is complex enough, you can try to make a program that uses IP ranges
I also have found geoipgen that is excellent except one thing. It doesn't save anything, it just outputs. Is there any way to implement "save" option to save the output to a file.
Here is a Ruby Code that I was saying about in comment(Only IP ranges):
#!/usr/bin/env ruby
#
# Turn IP Ranges into CSV output
# By: HR
#
# Now handles single input or loading via file:
# ipranges2csv.rb -f ranges.txt
# ipranges2csv.rb -s 192.168.2-3.1-25
#
# Output file, edit as needed
CSV_OUTPUT='ip_ranges.csv'
require 'optparse'
require 'colorize' # to install: sudo gem install colorize
# Trap Interupts, close cleanly
trap("SIGINT") {
puts "\n\nWARNING".light_red + "!".white + " CTRL".light_red + "+".white + "C Detected, Shutting things down".light_red + ".....\n\n".white
exit 666;
}
def banner
puts "IP Range to CSV Convertor".light_green
puts "By".light_green + ": HR".white
end
def cls
if RUBY_PLATFORM =~ /win32|win64|windows|WoW64|\.NET/i
system('cls')
else
system('clear')
end
end
# Breaks up IP range into array of all the unique single IP values
# Returns updated array that is primed for CSV writing
def range_convertor(iprange)
iprange.sub!(/\/\d+$/, '') # No CIDR Support here, sorry
blocks = iprange.split('.')[0..3] # Break our IP into array of smaller chunks for handling
# Setup our iteration sets for each block
d_range = []
if blocks[3] =~ /-/
(blocks[3].split('-')[0] .. blocks[3].split('-')[-1]).each {|i| d_range << i }
else
d_range << blocks[3]
end
c_range = []
if blocks[2] =~ /-/
(blocks[2].split('-')[0] .. blocks[2].split('-')[-1]).each {|i| c_range << i }
else
c_range << blocks[2]
end
b_range = []
if blocks[1] =~ /-/
(blocks[1].split('-')[0] .. blocks[1].split('-')[-1]).each {|i| b_range << i }
else
b_range << blocks[1]
end
a_range = []
if blocks[0] =~ /-/
(blocks[0].split('-')[0] .. blocks[0].split('-')[-1]).each {|i| a_range << i }
else
a_range << blocks[0]
end
# Now try to piece it all together
the_real_ranges = []
a_range.each {|z| b_range.each {|y| c_range.each {|x| d_range.each {|w| the_real_ranges << "#{z}.#{y}.#{x}.#{w}" } } } }
return the_real_ranges.uniq
end
# Main>
options = {}
optparse = OptionParser.new do |opts|
opts.banner = "Usage: #{$0} ".white + "[".light_green + "OPTIONS".white + "]".light_green
opts.separator ""
opts.separator "EX".light_green + ": #{$0} -f ip_ranges.txt".white
opts.separator "EX".light_green + ": #{$0} --file /tmp/ips.txt".white
opts.separator "EX".light_green + ": #{$0} -s '192.168.3-5.1-254'".white
opts.separator "EX".light_green + ": #{$0} --single '192.168.3-5.1-254'".white
opts.separator ""
opts.separator "Options".light_green + ": ".white
opts.on('-f', '--file FILE', "\n\tFile to load for CSV conversions (one IP/Range per line)".white) do |target|
if File.exists?(target.strip.chomp)
options[:method] = 2
options[:rangefile] = target.strip.chomp
else
puts "\nProblem finding IP Range file".light_red + "!".white
puts "Please check path or permissions and try again".light_red + ".....\n\n".white
exit 666;
end
end
opts.on('-s', '--single IP', "\n\tSingle IP Range to Convert to CSV".white) do |single|
options[:method] = 1
options[:single] = single.strip.chomp
end
opts.on('-h', '--help', "\n\tHelp Menu".white) do
cls
banner
puts
puts opts
puts
exit 69;
end
end
begin
foo = ARGV[0] || ARGV[0] = "-h" # if nothing passed, send to help menu
optparse.parse!
mandatory = [ :method ]
missing = mandatory.select{ |param| options[param].nil? } #freakout if they dont give us what we need!
if not missing.empty?
puts "Missing option(s)".light_red + ": #{missing.join(', ')}".white
puts
banner
puts optparse
puts
puts
exit
end
rescue OptionParser::InvalidOption, OptionParser::MissingArgument, OptionParser::AmbiguousOption
cls
puts $!.to_s.light_red
puts
banner
puts optparse
puts
puts
exit 666;
end
cls
banner
csv_ips=[]
if options[:method].to_i == 1
# Single IP Range
puts "\n\nConverting Single IP Range".light_green + ": #{options[:single]}".white
csv_ips = range_convertor(options[:single])
else
# Load IP Ranges from File
puts "\n\nConverting IP Ranges from File".light_green + ": #{options[:rangefile]}".white
fh=File.open(options[:rangefile])
fh.each do |line|
res = range_convertor(line.strip.chomp)
res.each {|ip| csv_ips << ip unless csv_ips.include?(ip)}
end
fh.close
end
# Write the converts to file
puts "Writing results to new CSV file".light_green + "....".white
fh=File.open(CSV_OUTPUT, 'w+')
fh.puts csv_ips.join(',')
fh.close
puts "Conversion complete, results can be found in".light_green + ": #{CSV_OUTPUT}\n\n".white
#EOF

unpack requires a string argument of length 24

I am not sure what I am doing wrong here but I am trying to open a file, trace1.flow, read the header information then throw the source IP and destination IP into dictionaries. This is done in Python running on a Fedora VM. I am getting the following error:
(secs, nsecs, booted, exporter, mySourceIP, myDestinationIP) = struct.unpack('IIIIII',myBuf)
struct.error: unpack requires a string argument of length 24
Here is my code:
import struct
import socket
#Dictionaries
uniqSource = {}
uniqDestination = {}
def int2quad(i):
z = struct.pack('!I', i)
return socket.inet_ntoa(z)
myFile = open('trace1.flow')
myBuf = myFile.read(8)
(magic, endian, version, headerLen) = struct.unpack('HBBI', myBuf)
print "Magic: ", hex(magic), "Endian: ", endian, "Version: ", version, "Header Length: ", headerLen
myFile.read(headerLen - 8)
try:
while(True):
myBuf = myFile.read(24)
(secs, nsecs, booted, exporter, mySourceIP, myDestinationIP) = struct.unpack('IIIIII',myBuf)
mySourceIP = int2quad(mySourceIP)
myDestinationIP = int2quad(myDestinationIP)
if mySourceIP not in uniqSource:
uniqSource[mySourceIP] = 1
else:
uniqSource[mySourceIP] += 1
if myDestinationIP not in uniqDestination:
uniqDestination[myDestinationIP] = 1
else:
uniqDestination[myDestinationIP] += 1
myFile.read(40)
except EOFError:
print "END OF FILE"

You seem to assume that file.read will raise EOFError on end of file, but this error is only raised by input() and raw_input(). file.read will simply return a string that's shorter than requested (possibly empty).
So you need to check the length after reading:
myBuf = myFile.read(24)
if len(myBuf) < 24:
break

Perhaps your have reached end-of-file. Check the length of myBuf:
len(myBuf)
It's probably less than 24 chars long. Also you don't need those extra parenthesis, and try to specify duplicated types using 'nI' like this:
secs, nsecs, booted, exporter, mySourceIP, myDestinationIP = struct.unpack('6I',myBuf)

Python - Changing File Object within function

Sorry - My questions is how can I change a file object within a function from a different function?
I've been trying to work out this error in my first python script for too long now, Dr Google and the forums aren't helping me too much, but I'm hoping you can.
I have a looping function that generates alot of data and I would like to output it to a text file, and create a new text file after the third loop.
I have 2 functions defined, one to create the data hashes, the other to create the new files.
The new files are being created as expected (aaa.txt, baa.txt...etc) but the "hashit" function only ever writes to the first file (aaa.txt) even though the others are being created.
I have tried fo.close() fo.flush(), as well as referencing fo in the functions but can't seem to make it work. Also I've moved the fo.write from the function to the main body.
I have included a cut down version of the code that I've been using to troubleshoot this issue, the real one has several more loops increasing the string length.
Thanks in advance
import smbpasswd, hashlib
base = '''abcdefghijklmnopqrstuvwxyz '''
# base length 95
print(base)
baselen = len(base)
name = 'aaa.txt'
fo = open(name, "w")
print "Name of the file: ", fo.name
print "Closed or not : ", fo.closed
print "Opening mode : ", fo.mode
print "Softspace flag : ", fo.softspace
pw01 = 0
pw02 = 0
pw03 = 0
def hashit(passwd):
#2
# Need to install module
# sudo apt-get install python-smbpasswd
hex_dig_lm = smbpasswd.lmhash(passwd)
hex_dig_ntlm = smbpasswd.nthash(passwd)
#print '%s:%s' % smbpasswd.hash(passwd)
hash_md5 = hashlib.md5(passwd)
hex_dig_md5 = hash_md5.hexdigest()
print(passwd)
print(hex_dig_lm)
print(hex_dig_ntlm)
print(hex_dig_md5)
hashstring = passwd +","+ hex_dig_lm +","+ hex_dig_md5 + '\n'
fo.write(hashstring);
def newfile(name):
fo.flush()
fo = open(name, "a")
print("-------newfile------")
print "Name of the file: ", fo.name
print "Closed or not : ", fo.closed
print('NewFile : ' + name)
raw_input("\n\nPress the enter key to exit.")
# add 3rd digit
while (pw03 < baselen):
pwc03 = base[pw03]
name = pwc03 + 'aa.txt'
fo.close
newfile(name);
pw03 += 1
while (pw02 < baselen):
pwc02 = base[pw02]
pw02 += 1
while (pw01 < baselen):
pwc01 = base[pw01]
pw01 += 1
passwd = pwc03 + pwc02 + pwc01
hashit(passwd);
else:
pw01 = 0
else:
pw02 = 0
else:
pw03 = 0

In your newfile() function, add this line first:
global fo

Userfriendly way of handling config files in python?

I want to write a program that sends an e-mail to one or more specified recipients when a certain event occurs. For this I need the user to write the parameters for the mail server into a config. Possible values are for example: serveradress, ports, ssl(true/false) and a list of desired recipients.
Whats the user-friendliest/best-practice way to do this?
I could of course use a python file with the correct parameters and the user has to fill it out, but I wouldn't consider this user friendly. I also read about the 'config' module in python, but it seems to me that it's made for creating config files on its own, and not to have users fill the files out themselves.

Are you saying that the fact that the config file would need to be valid Python makes it unfriendly? It seems like having lines in a file like:
server = 'mail.domain.com'
port = 25
...etc would be intuitive enough while still being valid Python. If you don't want the user to have to know that they have to quote strings, though, you might go the YAML route. I use YAML pretty much exclusively for config files and find it very intuitive, and it would also be intuitive for an end user I think (though it requires a third-party module - PyYAML):
server: mail.domain.com
port: 25
Having pyyaml load it is simple:
>>> import yaml
>>> yaml.load("""a: 1
... b: foo
... """)
{'a': 1, 'b': 'foo'}
With a file it's easy too.
>>> with open('myconfig.yaml', 'r') as cfile:
... config = yaml.load(cfile)
...
config now contains all of the parameters.

I doesn't matter technically proficient your users are; you can count on them to screw up editing a text file. (They'll save it in the wrong place. They'll use MS Word to edit a text file. They'll make typos.) I suggest making a gui that validates the input and creates the configuration file in the correct format and location. A simple gui created in Tkinter would probably fit your needs.

I've been using ConfigParser. It's designed to read .ini style files that have:
[section]
option = value
It's quite easy to use and the documentation is pretty easy to read. Basically you just load the whole file into a ConfigParser object:
import ConfigParser
config = ConfigParser.ConfigParser()
config.read('configfile.txt')
Then you can make sure the users haven't messed anything up by checking the options. I do so with a list:
OPTIONS =
['section,option,defaultvalue',
.
.
.
]
for opt in OPTIONS:
section,option,defaultval = opt.split(',')
if not config.has_option(section,option):
print "Missing option %s in section %s" % (option,section)
Getting the values out is easy too.
val = config.get('section','option')
And I also wrote a function that creates a sample config file using that OPTIONS list.
new_config = ConfigParser.ConfigParser()
for opt in OPTIONS:
section,option,defaultval = opt.split(',')
if not new_config.has_section(section):
new_config.add_section(section)
new_config.set(section, option, defaultval)
with open("sample_configfile.txt", 'wb') as newconfigfile:
new_config.write(newconfigfile)
print "Generated file: sample_configfile.txt"

What are the drawbacks of such a solution:
ch = 'serveradress = %s\nport = %s\nssl = %s'
a = raw_input("Enter the server's address : ")
b = 'a'
bla = "\nEnter the port : "
while not all(x.isdigit() for x in b):
b = raw_input(bla)
bla = "Take care: you must enter digits exclusively\n"\
+" Re-enter the port (digits only) : "
c = ''
bla = "\nChoose the ssl option (t or f) : "
while c not in ('t','f'):
c = raw_input(bla)
bla = "Take care: you must type f or t exclusively\n"\
+" Re-choose the ssl option : "
with open('configfile.txt','w') as f:
f.write(ch % (a,b,c))
.
PS
I've read in the jonesy's post that the value in a config file may have to be quoted. If so, and you want the user not to have to write him/her-self the quotes, you simply add
a = a.join('""')
b = b.join('""')
c = c.join('""')
.
EDIT
ch = 'serveradress = %s\nport = %s\nssl = %s'
d = {0:('',
"Enter the server's address : "),
1:("Take care: you must enter digits exclusively",
"Enter the port : "),
2:("Take care: you must type f or t exclusively",
"Choose the ssl option (t or f) : ") }
def func(i,x):
if x is None:
return False
if i==0:
return True
elif i==1:
try:
ess = int(x)
return True
except:
return False
elif i==2:
if x in ('t','f'):
return True
else:
return False
li = len(d)*[None]
L = range(len(d))
while True:
for n in sorted(L):
bla = d[n][1]
val = None
while not func(n,val):
val = raw_input(bla)
bla = '\n '.join(d[n])
li[n] = val.join('""')
decision = ''
disp = "\n====== If you choose to process, =============="\
+"\n the content of the file will be :\n\n" \
+ ch % tuple(li) \
+ "\n==============================================="\
+ "\n\nDo you want to process (type y) or to correct (type c) : "
while decision not in ('y','c'):
decision = raw_input(disp)
disp = "Do you want to process (type y) or to correct (type c) ? : "
if decision=='y':
break
else:
diag = False
while not diag:
vi = '\nWhat lines do you want to correct ?\n'\
+'\n'.join(str(j)+' - '+line for j,line in enumerate((ch % tuple(li)).splitlines()))\
+'\nType numbers of lines belonging to range(0,'+str(len(d))+') separated by spaces) :\n'
to_modify = raw_input(vi)
try:
diag = all(int(entry) in xrange(len(d)) for entry in to_modify.split())
L = [int(entry) for entry in to_modify.split()]
except:
diag = False
with open('configfile.txt','w') as f:
f.write(ch % tuple(li))
print '-*- Recording of the config file : done -*-'