Web サイトから URL を抽出するプログラムを作成しようとしています。出力は良好ですが、出力をファイルに書き込もうとすると、最後のレコードしか書き込まれません。コードは次のとおりです。
import re
import urllib.request
# Retrieves URLs from the HTML source code of a website
def extractUrls(url, unique=True, sort=True, restrictToTld=None):
# Prepend "www." if not present
if url[0:4] != "www.":
url = "".join(["www.",url])
# Open a connection
with urllib.request.urlopen("http://" + url) as h:
# Grab the headers
headers = h.info()
# Default charset
charset = "ISO-8859-1"
# If a charset is in the headers then override the default
for i in headers:
match = re.search(r"charset=([\w\-]+)", headers[i], re.I)
if match != None:
charset = match.group(1).lower()
break
# Grab and decode the source code
source = h.read().decode(charset)
# Find all URLs in the source code
matches = re.findall(r"http\:\/\/(www.)?([a-z0-9\-\.]+\.[a-z]{2,6})\b", source, re.I)
# Abort if no URLs were found
if matches == None:
return None
# Collect URLs
collection = []
# Go over URLs one by one
for url in matches:
url = url[1].lower()
# If there are more than one dot then the URL contains
# subdomain(s), which we remove
if url.count(".") > 1:
temp = url.split(".")
tld = temp.pop()
url = "".join([temp.pop(),".",tld])
# Restrict to TLD if one is set
if restrictToTld:
tld = url.split(".").pop()
if tld != restrictToTld:
continue
# If only unique URLs should be returned
if unique:
if url not in collection:
collection.append(url)
# Otherwise just add the URL to the collection
else:
collection.append(url)
# Done
return sorted(collection) if sort else collection
# Test
url = "msn.com"
print("Parent:", url)
for x in extractUrls(url):
print("-", x)
f = open("f2.txt", "w+", 1)
f.write( x )
f.close()
出力は次のとおりです。
Parent: msn.com
- 2o7.net
- atdmt.com
- bing.com
- careerbuilder.com
- delish.com
- discoverbing.com
- discovermsn.com
- facebook.com
- foxsports.com
- foxsportsarizona.com
- foxsportssouthwest.com
- icra.org
- live.com
- microsoft.com
- msads.net
- msn.com
- msnrewards.com
- myhomemsn.com
- nbcnews.com
- northjersey.com
- outlook.com
- revsci.net
- rsac.org
- s-msn.com
- scorecardresearch.com
- skype.com
- twitter.com
- w3.org
- yardbarker.com
[Finished in 0.8s]
ファイルには「yardbarker.com」のみが書き込まれます。助けてくれてありがとう、ありがとう。