Multiple Error Handling

[mh121]

Hi,

I am trying to input a spreadsheet of possible domain names and output the length of the sourcecode of the webpage (if it exists). In testing this, I’ve come across a lot of errors, for example, when websites ask for username/password, take too slow to load, or no longer work. I am a newbie and am looking for help dealing with multiple errors.

First, is the basic code setup below the best way to deal with multiple errors? I would like to have the program read the lines if possible, and return back null (or string=’’) if something goes wrong; do I have to do this ad hoc, adding new errors to my list each time I found one, or is there some way to say ‘return null if any error comes up?’

Second, how do I handle this error?

InvalidURL: nonnumeric port: ''

It seems to happen on z=urlopen('http://www.'+domainTerm)

Third, how do I handle this error?

error: (10054, 'Connection reset by peer')

It seems to happen on lineList=z.readlines()

Thank you,
Mitch

from mechanize import Browser
from urllib import urlopen
import re, time, urllib2, string
 
f = open('rawST2.csv','r')
lines = f.readlines()
f.close()
f2 = open('toy4.csv','w')
f2.write(lines[0].rstrip()+',sourcelines'+',sourcecharacters' +"\n")
print(lines[0].rstrip()+",sourcelines"+",sourcecharacters)
 
domainTerms=[]
for i in range(1,len(lines)):
    domainTerms.append( lines[i].split(',')[5].rstrip() )
 
x = domainTerms[59]
domainTerm=string.replace(x,x[0],"")
 
try: 
  z=urlopen('http://www.'+domainTerm)
  lineList=z.readlines()
except (urllib2.URLError, ValueError, IOError, AttributeError, TypeError):
  lineList=""
 

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