Groovy执行shell命令

Question

Groovy添加了execute方法,String使执行shell相当容易;

println "ls".execute().text

但如果发生错误,则没有结果输出. 是否有一种简单的方法可以同时获得标准错误和标准错误？ (除了创建一堆代码;创建两个线程来读取两个输入流,然后使用父流等待它们完成然后将字符串转换回文本？)

有类似的东西会很高兴;

 def x = shellDo("ls /tmp/NoFile")
 println "out: ${x.out} err:${x.err}"

Answer 1

好的,我自己解决了;

def sout = new StringBuilder(), serr = new StringBuilder()
def proc = 'ls /badDir'.execute()
proc.consumeProcessOutput(sout, serr)
proc.waitForOrKill(1000)
println "out> $sout err> $serr"

显示:

out> err> ls: cannot access /badDir: No such file or directory

Answer 2

"ls".execute()返回一个Process对象,这就是为什么"ls".execute().text有效.您应该能够只读取错误流以确定是否有任何错误.

有一个额外的方法Process允许您传递一个StringBuffer来检索文本:consumeProcessErrorStream(StringBuffer error).

例:

def proc = "ls".execute()
def b = new StringBuffer()
proc.consumeProcessErrorStream(b)

println proc.text
println b.toString()

Answer 3

// a wrapper closure around executing a string                                  
// can take either a string or a list of strings (for arguments with spaces)    
// prints all output, complains and halts on error                              
def runCommand = { strList ->
  assert ( strList instanceof String ||
           ( strList instanceof List && strList.each{ it instanceof String } ) \
)
  def proc = strList.execute()
  proc.in.eachLine { line -> println line }
  proc.out.close()
  proc.waitFor()

  print "[INFO] ( "
  if(strList instanceof List) {
    strList.each { print "${it} " }
  } else {
    print strList
  }
  println " )"

  if (proc.exitValue()) {
    println "gave the following error: "
    println "[ERROR] ${proc.getErrorStream()}"
  }
  assert !proc.exitValue()
}

Answer 4

在上面提供的答案中添加一个更重要的信息 -

对于一个过程

def proc = command.execute();

总是试着用

def outputStream = new StringBuffer();
proc.waitForProcessOutput(outputStream, System.err)
//proc.waitForProcessOutput(System.out, System.err)

而不是

def output = proc.in.text;

在groovy中执行命令后捕获输出,因为后者是阻塞调用(原因是SO问题).

Answer 5

我觉得这更惯用:

def proc = "ls foo.txt doesnotexist.txt".execute()
assert proc.in.text == "foo.txt\n"
assert proc.err.text == "ls: doesnotexist.txt: No such file or directory\n"

正如另一篇文章提到的,这些是阻塞调用,但由于我们想要使用输出,这可能是必要的.

Answer 6

def exec = { encoding, execPath, execStr, execCommands ->

def outputCatcher = new ByteArrayOutputStream()
def errorCatcher = new ByteArrayOutputStream()

def proc = execStr.execute(null, new File(execPath))
def inputCatcher = proc.outputStream

execCommands.each { cm ->
    inputCatcher.write(cm.getBytes(encoding))
    inputCatcher.flush()
}

proc.consumeProcessOutput(outputCatcher, errorCatcher)
proc.waitFor()

return [new String(outputCatcher.toByteArray(), encoding), new String(errorCatcher.toByteArray(), encoding)]

}

def out = exec("cp866", "C:\\Test", "cmd", ["cd..\n", "dir\n", "exit\n"])

println "OUT:\n" + out[0]
println "ERR:\n" + out[1]