Python Penetration Testing Cookbook

Escaping invalid characters

In the previous recipe, what will happen if we remove the try catch block in the last step?

patten = '(http)?s?:?(\/\/[^"]*\.(?:png|jpg|jpeg|gif|png|svg))' 
for line in open('packtpub.txt'): 
    for m in re.findall(patten, line):          
        fileName = basename(urlsplit(m[1])[2])                
        img = urllib2.urlopen('https:' + m[1]).read() 
        file = open(fileName, "w") 
        file.write(img) 
        file.close()          break 

The script will fail after a few requests due to the error in the URL format. Some extra characters appeared in the URL and this failed the urllib request.