如何使用PHP和远程ssh从文本文件中获取信息？

Question

I've got this problem with very poor performance with PHP executing bash script with remote ssh and doing a grep on a log. In web browser I receive output after 40 seconds. Executing bash script(ssh + grep on remote machine) directly over my local machine is taking 8 seconds. I know I cannot bypass this so I came up with idea of :

Creating PHP script which will save to a text file on a local machine all "variables" I need. Let's call it "parameters.txt". Then other bash script "reader.sh" will read this "parameters.txt" file, do all of the magic of remote ssh and grep, then save output to "output.txt". Background script will run every 2 seconds the reader.sh

Is it a good idea?

Answer 1

If you really need to use PHP over SSH, you could use something like http://phpseclib.sourceforge.net/ . They have a nice ssh implementation which I used for sometime for deploy applications and configure Linux servers (puppet replaced it). Your code will be cleaner and easy to maintain.

Another option is, if you are reading logs from Linux ( messages, apache, syslog, etc...) you have options with Rsyslog ( http://www.rsyslog.com/ ) to centralize it on a server and work on it locally. This would be cheaper for your computers and easier to deploy.

Answer 2

Here is how you do it fast. I recently published a project that allows PHP to obtain and interact with a real Bash shell, even through SSH. Get it here: https://github.com/merlinthemagic/MTS

After downloading you would simply use the following code:

$shell = \MTS\Factories::getDevices()->getRemoteHost('ip_address')->getShellBySsh('username', 'secretPassword');

//execute the grep command
$return1  = $shell->exeCmd("cat /full/path/to/logfile | grep \"someExpression\"");

echo $return1; //contains all the return that matched the grep expression