需要幫助理解python片段與正則表達式和cURL

Question

編輯 - 剛剛添加了整個cURL函數以供參考/更多信息，但需要if語句的幫助 - 正則表達式

尋求幫助以理解此cURL中的if語句。 我已經閱讀了一些python文檔，我理解了每個部分，這是用正則表達式進行搜索和替換。 只是希望有人能夠幫助提供更大的解釋。 我真的不明白.groups。

為了給出更多背景，這個腳本通過cURL訪問另一個站點，它存儲一個cookie，當運行時檢查cookie是否有效，如果沒有，它會在發布用戶名/密碼后抓取一個新的。 該網站最近發生了變化，我正在試圖弄清楚我需要改變什么才能讓它再次運作。

#get auth cookie for sso
def getAuthCookie( self ):
    buffer = BytesIO()
    c = pycurl.Curl()
    c.setopt(c.SSL_VERIFYPEER, False)
    c.setopt(c.FOLLOWLOCATION, True)
    c.setopt(c.TIMEOUT, 60)
    c.setopt(c.USERPWD, self.user+":"+cred.getpasswd( self.encPasswd ) )
    c.setopt(c.URL, 'https://sso.sample.com')
    c.setopt(c.COOKIEJAR, self.cookieDir)
    c.setopt(c.COOKIEFILE, self.cookieDir )
    c.setopt(c.WRITEFUNCTION, buffer.write)
    c.perform()
    c.unsetopt(c.USERPWD)
    c.setopt(c.URL, 'https://sample.com')
    c.perform()
    html = str(buffer.getvalue())    

----------------------------------------------------------
if "RelayState" in html:
    rex = re.compile( "input type=\"hidden\" name=\"RelayState\" value=\"(.*)\"" )
    RELAY = rex.search( html ).groups()[0]
if "SAMLResponse" in html:
    rex = re.compile( "input type=\"hidden\" name=\"SAMLResponse\" value=\"(.*)\"" )
    SAML =  rex.search( html ).groups()[0]
    datastuff = {'SAMLResponse':SAML,'RelayState':RELAY,'redirect':'Redirect','show_button':'true'}
if "form method=\"POST\" action=" in html:
    rex = re.compile( "form method=\"POST\" action=\"(.*)\" " )
    postUrl = rex.search( html ).groups()[0]
---------------------------------------------------------- 

#post our saml obtained, get to our final dest
    c.setopt(c.URL, postUrl )
    c.setopt(c.POST, True)
    c.setopt(c.POSTFIELDS, urlencode( datastuff ))
    c.perform()
    c.close()

Answer 1

請參閱我在代碼中注入的注釋：

#get auth cookie for sso
def getAuthCookie( self ):
    buffer = BytesIO()
    c = pycurl.Curl()
    c.setopt(c.SSL_VERIFYPEER, False)
    c.setopt(c.FOLLOWLOCATION, True)
    c.setopt(c.TIMEOUT, 60)
    c.setopt(c.USERPWD, self.user+":"+cred.getpasswd( self.encPasswd ) )
    # curling sso.sample.com, which I assume promts a login dialog box and curl will set that with the varible provide above
    c.setopt(c.URL, 'https://sso.sample.com')
    # save the cookie to cookieDir
    c.setopt(c.COOKIEJAR, self.cookieDir)
    c.setopt(c.COOKIEFILE, self.cookieDir )
    c.setopt(c.WRITEFUNCTION, buffer.write)
    # perform all the previous curl commands
    c.perform()
    c.unsetopt(c.USERPWD)
    # curl new site sample.com
    c.setopt(c.URL, 'https://sample.com')
    c.perform()
    # save output as html var
    html = str(buffer.getvalue())    

----------------------------------------------------------
# The following three if statments
# if "some string is found" in varible-html: then do the lines indented lines that follow
if "RelayState" in html:
    # setup a regex to look for "input type="hidden" name="RelayState" value="[and captures everything here this will become the RELAY var]"
    rex = re.compile( "input type=\"hidden\" name=\"RelayState\" value=\"(.*)\"" )
    # this executes the regex expression on the html var
    RELAY = rex.search( html ).groups()[0]
if "SAMLResponse" in html:
    rex = re.compile( "input type=\"hidden\" name=\"SAMLResponse\" value=\"(.*)\"" )
    # same thing is happening here capturing the value as SAML
    SAML =  rex.search( html ).groups()[0]
    # contructing a new var with strings and the newly contructed vars
    datastuff = {'SAMLResponse':SAML,'RelayState':RELAY,'redirect':'Redirect','show_button':'true'}
if "form method=\"POST\" action=" in html:
    rex = re.compile( "form method=\"POST\" action=\"(.*)\" " )
    # again action="[postURL]"
    postUrl = rex.search( html ).groups()[0]
---------------------------------------------------------- 

#post our saml obtained, get to our final dest
    c.setopt(c.URL, postUrl ) # setup curl with url found above
    c.setopt(c.POST, True) # use post method
    c.setopt(c.POSTFIELDS, urlencode( datastuff )) # post fields found above with newly contructed vars
    c.perform()
    c.close()

如果某些內容發生了變化並且您現在收到錯誤，我會嘗試在html = str(buffer.getvalue())之后print html ，看看您是否仍然在尋找正在執行的正則表達式的同一頁面。