def robotsrulesetOfDomain(self, domain):
		'''检查domain是否在数据库中,
			否 --> (False, None)
			是 --> (True, 数据库中存储的robots.txt内容)
		'''
		exist = False
		cur = self.conn.cursor()
		# 是否存在
		cur.execute("SELECT 1 FROM Domains WHERE domain=?", (domain,))
		if cur.fetchone() :
			exist = True
		# 存在的话,结果是什么
		cur.execute("SELECT rules FROM Domains,Rulesets "
			"WHERE domain=? AND Domains.did=Rulesets.did"
			,(domain,) )
		ruleset = cur.fetchone()
		return (exist, ruleset)
def image_thumbnail(filename):
    filepath = os.path.join(app.config.get('UPLOAD_FOLDER'), filename)
    im = Image.open(filepath)
    w, h = im.size

    if w > h:
        im.thumbnail((106, 106*h/w))
    else:
        im.thumbnail((106*w/h, 106))

    im.save(os.path.join(app.config.get('UPLOAD_FOLDER'), 
        os.path.splitext(filename)[0] + '_thumbnail' + os.path.splitext(filename)[1]))