Expect概述

Expect是一个用来实现自动交互功能的软件套件 (Expect [is a] software suite for automating interactive tools)

Expect使用

Expect通过匹配关键字自动推送参数到脚本中，将人机交互操作转化为自动执行。

1.基本例子(设置文件权限)

#!/usr/bin/expect -f

set timeout 10

set dbf_dir [lindex $argv 0]

set passwd [lindex $argv 1]

spawn su - oracle

expect "*Password*"

send "$passwd\r"

expect ">"

send "chmod 750 $dbf_dir/tbs_test_*.dbf\r"

expect ">"

send "exit\r"

expect eof

2.明文密码处理(敏感参数通过流的方式传递到脚本中，ps -ef获取到的进程信息中便不会显示敏感信息)

expect脚本获取敏感参数

expect_user -re "(.*)\n"

set oracle_passwd $expect_out(1,string)

shell脚本获取敏感参数

INPUT_PWD=""

read -p "Enter Password :" INPUT_PWD

expect举例

#!/usr/bin/expect -f

set timeout 10

set ip_addr [lindex $argv 0]

spawn ssh oracle@$ip_addr

expect_user -re "(.*)\n"

set oracle_passwd $expect_out(1,string)

expect {

"Are you sure you want to continue connecting" {

send "yes\r"

expect "*Password*"

send "$oracle_passwd\r"

}

"*Password*" {

send "$oracle_passwd\r"

}

}

expect ">"

send "sqlplus / as sysdba\r"

expect ">"

send "purge dba_recyclebin;\r"

expect ">"

send "exit\r"

expect ">"

send "exit\r"

expect eof

//调用脚本，传入敏感参数的公共类

public static int executeCmd(String cmdType, String cmdFile, List normalParas, List pwdParas)

{

int result = 0;

try

{

ArrayList allParas = new ArrayList();

allParas.add(cmdType);

allParas.add(cmdFile);

allParas.addAll(normalParas);

ProcessBuilder builder = new ProcessBuilder();

builder.command(allParas);

Process process = builder.start();

OutputStream os = process.getOutputStream();

for (int i = 0; i < pwdParas.size(); i++)

{

os.write((pwdParas.get(i) + "\n").getBytes("UTF-8"));

}

os.flush();

StreamGobbler errorGobbler = new StreamGobbler(process.getErrorStream(), "ERROR");

errorGobbler.start();

StreamGobbler outGobbler = new StreamGobbler(process.getInputStream(), "STDOUT");

outGobbler.start();

result = process.waitFor();

}

catch (Exception e){...}

return result;

}

//调用方式

RuntimeUtil.executeCmd("expect", "脚本路径", normalParas, pwdParas);

//读取输出流的公共类

public class StreamGobbler extends Thread

{

private static final int MAX_BLOCK_SIZE = 8192;

private static final int INPUT_BUFFER_SIZE = 2048;

InputStream is;

String type;

public StreamGobbler(InputStream isPt, String typePt)

{

this.is = isPt;

this.type = typePt;

}

public void run()

{

BoundedInputStream bisPt = null;

BufferedReader brPt = null;

try

{

bisPt = new BoundedInputStream(is, StreamGobbler.MAX_BLOCK_SIZE);

brPt = new BufferedReader(new InputStreamReader(bisPt, "UTF-8"), StreamGobbler.INPUT_BUFFER_SIZE);

while ((brPt.readLine()) != null)

{//NOPMD

}//NOPMD

}

catch (IOException ioe){...}

finally

{

if (brPt != null)

{

try

{

brPt.close();

}

catch (IOException e){...}

}

if (bisPt != null)

{

try

{

bisPt.close();

}

catch (IOException e){...}

}

}

}

}