使用Scala中的正则表达式从服务器日志字符串中提取路径

Question

我有几根像下面这样的圆木

endeavor.fujitsu.co.jp - - [10/Jul/1995:00:00:15 -0400] "GET /images/ HTTP/1.0" 200 17688                                   
ad13-022.compuserve.com - - [10/Jul/1995:00:00:15 -0400] "GET /history/gemini/gemini-spacecraft.txt HTTP/1.0" 200 651       
pm2-15.magicnet.net - - [10/Jul/1995:00:00:15 -0400] "GET /images/launch-logo.gif HTTP/1.0" 200 1713                        
204.239.199.40 - - [10/Jul/1995:00:00:16 -0400] "GET /shuttle/missions/sts-71/images/KSC-95EC-0613.gif HTTP/1.0" 200 45970  
pm1-4.tricon.net - - [10/Jul/1995:00:00:17 -0400] "GET /images/WORLD-logosmall.gif HTTP/1.0" 200 669                        
scorpio.digex.net - - [10/Jul/1995:00:00:19 -0400] "GET /history/mercury/mr-3/mr-3.html HTTP/1.0" 200 1124

我需要从上面的日志中提取路径。这是我试过的代码

val pattern = "\\s+([^\\s]+)\\s+HTTP".r
val match = pattern.findFirstIn(log)

这是我得到的输出。

/images/ HTTP
/history/gemini/gemini-spacecraft.txt HTTP
/images/launch-logo.gif HTTP
/shuttle/missions/sts-71/images/KSC-95EC-0613.gif HTTP
/images/WORLD-logosmall.gif HTTP
/history/mercury/mr-3/mr-3.html HTTP

如何摆脱上述路径中的HTTP？

Answer 1

你的对手在第一组，

另外，您也可以使用正向前瞻。

\\s+[^\\s]+(?=\\s+HTTP)

演示

​

​

Answer 2

您的匹配位于第一个捕获组()中，您可以将其缩短为：

\s(\S+)\s+HTTP 

在斯卡拉

val pattern = "\\s(\\S+)\\s+HTTP".r

Regex演示

您可以使用findAllIn获得日志：

val pattern = "\\s(\\S+)\\s+HTTP".r
val strings = List(
  """endeavor.fujitsu.co.jp - - [10/Jul/1995:00:00:15 -0400] "GET /images/ HTTP/1.0" 200 17688                                   """,
  """ad13-022.compuserve.com - - [10/Jul/1995:00:00:15 -0400] "GET /history/gemini/gemini-spacecraft.txt HTTP/1.0" 200 651       """,
  """pm2-15.magicnet.net - - [10/Jul/1995:00:00:15 -0400] "GET /images/launch-logo.gif HTTP/1.0" 200 1713                        """,
  """204.239.199.40 - - [10/Jul/1995:00:00:16 -0400] "GET /shuttle/missions/sts-71/images/KSC-95EC-0613.gif HTTP/1.0" 200 45970  """,
  """pm1-4.tricon.net - - [10/Jul/1995:00:00:17 -0400] "GET /images/WORLD-logosmall.gif HTTP/1.0" 200 669                        """,
  """scorpio.digex.net - - [10/Jul/1995:00:00:19 -0400] "GET /history/mercury/mr-3/mr-3.html HTTP/1.0" 200 1124"""
)

strings.foreach { log =>
  val m = pattern.findAllIn(log).group(1)
  println(m)
}

结果

/images/
/history/gemini/gemini-spacecraft.txt
/images/launch-logo.gif
/shuttle/missions/sts-71/images/KSC-95EC-0613.gif
/images/WORLD-logosmall.gif
/history/mercury/mr-3/mr-3.html

Scala演示

若要与注释中的该行匹配，请执行以下操作：

columbia.acc.brad.ac.uk -10/7/1995:00:52:36 -0400 "GET /ksc.html“200 7067

你可以使用：

\S+ (/(?:[^/\s]+/)*[^\s"]+)

Regex演示