Best/easiest way to parse configuration parameters in Sh/Bash and php - php

I got in every php project (around 25!), some sh scripts that help me with routine tasks such as deployment, repo syncronizing, databases exporting/export, etc.
The sh scripts are the same for all the projects I manage, so there must be a configuration file to store diferent parameters that depend on the project:
# example conf, the sintaxys only needs to be able to have comments and be easy to edit.
host=www.host.com
administrator_email=guill#company.com
password=xxx
I just need to find a clean way in which this configuration file can be read (parsed) from a sh script, and at the same time, be able to read those same parameters from my PHP scripts. Without having to use XML.
Do you know a good solution for this?
Guillermo

Simply source the script conf file as another sh file!.
Example:
conf-file.sh:
# A comment
host=www.host.com
administrator_email=guill#company.com
password=xxx
Your actual script:
#!/bin/sh
. ./conf-file.sh
echo $host $administrator_email $passwword
And the same conf-file can be parsed in PHP: http://php.net/manual/en/function.parse-ini-file.php

If you don't want to source the file as pavanlimo showed, another option is to pull in the variables using a loop:
while read propline ; do
# ignore comment lines
echo "$propline" | grep "^#" >/dev/null 2>&1 && continue
# if not empty, set the property using declare
[ ! -z "$propline" ] && declare $propline
done < /path/to/config/file
In PHP, the same basic concepts apply:
// it's been a long time, but this is probably close to what you need
function isDeclaration($line) {
return $line[0] != '#' && strpos($line, "=");
}
$filename = "/path/to/config/file";
$handle = fopen($filename, "r");
$contents = fread($handle, filesize($filename));
$lines = explode("\n", $contents); // assuming unix style
// since we're only interested in declarations, filter accordingly.
$decls = array_filter($lines, "isDeclaration");
// Now you can iterator over $decls exploding on "=" to see param/value
fclose($handle);

For a Bash INI file parser also see:
http://ajdiaz.wordpress.com/2008/02/09/bash-ini-parser/

to parse the ini file from sh/bash
#!/bin/bash
#bash 4
shopt -s extglob
while IFS="=" read -r key value
do
case "$key" in
!(#*) )
echo "key: $key, value: $value"
array["$key"]="$value"
;;
esac
done <"file"
echo php -r myscript.php ${array["host"]}
then from PHP, use argv

INI! http://php.net/manual/en/function.parse-ini-file.php

Related

shell_exec() always returning an empty string

I am trying to create a server within my Android phone. I am unable to execute any shell script from my PHP code.
Here's the code:
//index.php
<?php
$output=shell_exec("sdcard/htdocs/myscript.sh 2>&1");
if(!$output){
echo "Failed";
}else{
echo $output;
}
?>
//myscript.sh
cd sdcard/htdocs/images
ls -t1 | head -n 1
The script works fine within terminal emulator. I also tried changing permissions of the script file but that didn't work. I don't know if it requires superuser permissions to execute shell scripts within PHP code.
The whole code is used to return the filename of the last file created in the images directory.
Need suggestions to make this code work.Is there any other way to perform the required job?
Make sure what you have run
chmod a+x sdcard/htdocs/myscript.sh
on your file.
Also $output is not a boolean.
Your code looks fine. Superuser permission is not necessary for script execution. You should turn on PHP error output or check the PHP error log file. I bet you find the reason there. If not, recheck the directory, and file permissions:
./index.php
./sdcard/htdocs/myscript.sh
./sdcard/htdocs/images
sdcard and sdcard/htdocs require executable persmissions. sdcard/htdocs/images requires executable and read permission (ls in myscript.sh), and so does sdcard/htdocs/myscript.sh. But I guess it's something else because permission errors should be displayed (2>&1).
Edit
You can find the last modified file with PHP, no need to run another process. Take one of these two:
$images = glob('sdcard/htdocs/images/*');
$images = array_combine(array_map('filemtime', $images), $images);
asort($images);
echo $lastModifiedImage = end($images);
Or with some fewer array operations:
$images = glob('sdcard/htdocs/images/*');
array_reduce($images, function($previous, $element) use (&$found) {
$mtime = filemtime($element);
$found = $previous < $mtime ? $found : $element;
return $previous < $mtime ? $mtime : $previous;
}, 0);
echo $found;
sdcard and sdcard/htdocs require executable persmissions. sdcard/htdocs/images requires executable and read permission (ls in myscript.sh), and so does sdcard/htdocs/myscript.sh. But I guess it's something else because permission errors should be displayed (2>&1).
Probably FAT !

Pipe stdin into a shell script through php

We have a command line php application that maintains special permissions and want to use it to relay piped data into a shell script.
I know that we can read STDIN with:
while(!feof(STDIN)){
$line = fgets(STDIN);
}
But how can I redirect that STDIN into a shell script?
The STDIN is far too large to load into memory, so I can't do something like:
shell_exec("echo ".STDIN." | script.sh");
Using xenon's answer with popen seems to do the trick.
// Open the process handle
$ph = popen("./script.sh","w");
// This puts it into the file line by line.
while(($line = fgets(STDIN)) !== false){
// Put in line from STDIN. (Note that you may have to use `$line . '\n'`. I don't know
fputs($ph,$line);
}
pclose($ph);
As #Devon said, popen/pclose are very useful here.
$scriptHandle = popen("./script.sh","w");
while(($line = fgets(STDIN)) !== false){
fputs($scriptHandle,$line);
}
pclose($scriptHandle);
Alternatively, something along the lines of fputs($scriptHandle, file_get_contents("php://stdin")); might work in the place of a line-by-line approach for a smaller file.

Can't execute external process with PHP

I have the following code
function generate_pdf() {
$fdf_data_strings = $this->get_hash_for_pdf();
#$fdf_data_names = array('49a' => "yes");
$fdf_data_names = array();
$fields_hidden = array();
$fields_readonly = array();
$hud_pdf = ABSPATH.'../pdf/HUD3.pdf';
$fdf= forge_fdf( '',
$fdf_data_strings,
$fdf_data_names,
$fields_hidden,
$fields_readonly );
/* echo "<pre>";
print_r($fdf);
echo "</pre>";
die('');
*/
$fdf_fn= tempnam( '.', 'fdf' );
$fp= fopen( $fdf_fn, 'w' );
if( $fp ) {
fwrite( $fp, $fdf );
//$data=fread( $fp, $fdf );
// echo $data;
fclose( $fp );
header( 'Content-type: application/pdf' );
header( 'Content-disposition: attachment; filename=settlement.pdf' ); // prompt to save to disk
passthru( 'pdftk HUD3.pdf fill_form '. $fdf_fn.' output - flatten');
unlink( $fdf_fn ); // delete temp file
}
else { // error
echo 'Error: unable to open temp file for writing fdf data: '. $fdf_fn;
}
}
}
is there anything wrong with it?
the problem is, I have installed pdftk
runing whereis pdftk gives me '/usr/local/bin/pdftk'
physically checked the location, pdftk is there at the said location..
using terminal, if i run pdftk --version or any other command, it runs
if I use php like passthru('/usr/local/bin/pdftk --version') nothing is displayed
if I used php like system("PATH=/usr/local/bin && pdftk --version"); it says '/usr/local/bin /pdftk :there is no directory of file '
when I run this function script , prompt for file download pops, but when i save it, nothng is saved,
i have checked permission for this folder and changed it 0755, 0766, 0777, 0666 i have tried all, nothng works
For 3 days, i am striving to get over it, and I have asked question regarding this too, but Can't figure out what the hell is going on with me.
Can somebody help me before i strike my head with wall?
The pasthru function does not execute the program through the shell.
Pass the exact path into the passthru command.
E.g.
passthru( '/usr/local/bin/pdftk HUD3.pdf fill_form '. $fdf_fn.' output - flatten');
or
passthru( '/usr/local/bin/pdftk' . $hud_pdf . 'fill_form '. $fdf_fn.' output - flatten');
If this still doesn't work test using
<?php passthru("/path/to/pdftk --help"); ?> where /path/to/pdftk is your path returned by which or where is, to ensure path is correct.
If path is correct then the issue may be related to permissions either on the temporary directory you tell pdftk to use or the permissions on the pdftk binary with regards to the apache user.
If these permissions are fine you can verify the pdftk starts up from php but hangs from running your command, then might be able to try the workaround listed here.
Further documentation on passthru is avaliable passthru PHP Manual.
As a side note, the putenv php function is used to set environment variables.
E.g. putenv('PATH='.getenv('PATH').':.');
All 3 PHP functions: exec(), system() and passthru() executes an external command, but the differences are:
exec(): returns the last line of output from the command and flushes nothing.
shell_exec(): returns the entire output from the command and flushes nothing.
system(): returns the last line of output from the command and tries to flush the output buffer after each line of the output as it goes.
passthru(): returns nothing and passes the resulting output without interference to the browser, especially useful when the output is in binary format.
Also see PHP exec vs-system vs passthru SO Question.
The implementation of these functions is located at exec.c and uses popen.
I had the same issue and this is working after lots of experiments :
function InvokePDFtk($pdf_tpl, $xfdf,$output){
$params=" $pdf_tpl fill_form $xfdf output $output flatten 2>&1";
$pdftk_path=exec('/usr/bin/which /usr/local/bin/pdftk');
$have_pdftk= $pdftk_path=='/usr/local/bin/pdftk' ;
$pdftk_path=$have_pdftk ? $pdftk_path : 'pdftk ';
exec($pdftk_path.$params,$return_var);
return array('status'=> $have_pdftk,
'command' =>$pdftk_path.$params, 'output'=>$return_var);
}
hope this might give you some insight . (change according to your needs)
Completing Appleman answer, those 3 functions can be considered as dangerous, because they allow you execute program using php, thus an attacker that exploited one of your script if you are not careful enougth. So in many php configuration that want to be safe they are disabled.
So you should check for the disable_functions directive in you php.ini(and any php configuration file) and see if the function you use is disabled.
Perhaps you should keep fclose out of the if statement, make sure you have it directed to the right file! :)
Is your web server chrooted? Try putting the executable into a directory that is viewable by the server.
Play around around with safe mode and definitely check your web server log file, normally in:
/var/log/apache2/error.log

How do you pass the stdout to a linux terminal as an argument in a php script?

There's a program called getID3 (written in php) that copies all the id3 tags from your music and prints it out in text form: http://getid3.sourceforge.net/
There's one function that requires the path of your song and I would like to write some code to automate the whole process so that I can provide just the path of the parent directory, and all the songs in all the sub directories can have their id3 information printed out for me.
I want to get all the paths of the songs by using this BASH command:
find /myMusic -type f
And load each path from the BASH command as an element in a PHP array (let's say $song_information) where the array is
find /myMusic -type f |wc -l
elements long.
I'm stuck because I don't know how to get the output from the BASH terminal to an array in php. My first line of thinking was pipe the output of the bash command to an .xml file and then use a php.xml parser to load each path into an array.
Is this line of thinking a good approach or is there a better way?
The tools I have available are linux and php. I'm using ubuntu 10.04.
<?php
$list = array();
exec ( 'find /myMusic -type f', $list );
?>
"Input/output streams"
fgets()
If $a is an array then assigning to $a[] will append an element.
Your PHP can look like this:
#!/usr/bin/php
<?
$stdin = fopen('php://stdin', 'r');
while (($buffer = fgets($stdin, 4096)) !== false) {
$lines[] = $buffer;
}
fclose($stdin);
print_r($lines);
?>
and you pipe the results to it via
find /myMusic -type f | ./yourscript.php

how to redirect STDOUT to a file in PHP?

The code below almost works, but it's not what I really meant:
ob_start();
echo 'xxx';
$contents = ob_get_contents();
ob_end_clean();
file_put_contents($file,$contents);
Is there a more natural way?
It is possible to write STDOUT directly to a file in PHP, which is much easier and more straightforward than using output bufferering.
Do this in the very beginning of your script:
fclose(STDIN);
fclose(STDOUT);
fclose(STDERR);
$STDIN = fopen('/dev/null', 'r');
$STDOUT = fopen('application.log', 'wb');
$STDERR = fopen('error.log', 'wb');
Why at the very beginning you may ask? No file descriptors should be opened yet, because when you close the standard input, output and error file descriptors, the first three new descriptors will become the NEW standard input, output and error file descriptors.
In my example here I redirected standard input to /dev/null and the output and error file descriptors to log files. This is common practice when making a daemon script in PHP.
To write to the application.log file, this would suffice:
echo "Hello world\n";
To write to the error.log, one would have to do:
fwrite($STDERR, "Something went wrong\n");
Please note that when you change the input, output and error descriptors, the build-in PHP constants STDIN, STDOUT and STDERR will be rendered unusable. PHP will not update these constants to the new descriptors and it is not allowed to redefine these constants (they are called constants for a reason after all).
here's a way to divert OUTPUT which appears to be the original problem
$ob_file = fopen('test.txt','w');
function ob_file_callback($buffer)
{
global $ob_file;
fwrite($ob_file,$buffer);
}
ob_start('ob_file_callback');
more info here:
http://my.opera.com/zomg/blog/2007/10/03/how-to-easily-redirect-php-output-to-a-file
None of the answers worked for my particular case where I needed a cross platform way of redirecting the output as soon as it was echo'd out so that I could follow the logs with tail -f log.txt or another log viewing app.
I came up with the following solution:
$logFp = fopen('log.txt', 'w');
ob_start(function($buffer) use($logFp){
fwrite($logFp, $buffer);
}, 1); //notice the use of chunk_size == 1
echo "first output\n";
sleep(10)
echo "second output\n";
ob_end_clean();
I haven't noticed any performance issues but if you do, you can change chunk_size to greater values.
Now just tail -f the log file:
tail -f log.txt
No, output buffering is as good as it gets. Though it's slightly nicer to just do
ob_start();
echo 'xxx';
$contents = ob_get_flush();
file_put_contents($file,$contents);
Using eio pecl module eio is very easy, also you can capture PHP internal errors, var_dump, echo, etc. In this code, you can found some examples of different situations.
$fdout = fopen('/tmp/stdout.log', 'wb');
$fderr = fopen('/tmp/stderr.log', 'wb');
eio_dup2($fdout, STDOUT);
eio_dup2($fderr, STDERR);
eio_event_loop();
fclose($fdout);
fclose($fderr);
// output examples
echo "message to stdout\n";
$v2dump = array(10, "graphinux");
var_dump($v2dump);
// php internal error/warning
$div0 = 10/0;
// user errors messages
fwrite(STDERR, "user controlled error\n");
Call to eio_event_loop is used to be sure that previous eio requests have been processed. If you need append on log, on fopen call, use mode 'ab' instead of 'wb'.
Install eio module is very easy (http://php.net/manual/es/eio.installation.php). I tested this example with version 1.2.6 of eio module.
You can install Eio extension
pecl install eio
and duplicate a file descriptor
$temp=fopen('/tmp/my_stdout','a');
$my_data='my something';
$foo=eio_dup2($temp,STDOUT,EIO_PRI_MAX,function($data,$esult,$request){
var_dump($data,$esult,$request);
var_dump(eio_get_last_error($request));
},$my_data);
eio_event_loop();
echo "something to stdout\n";
fclose($temp);
this creates new file descriptor and rewrites target stream of STDOUT
this can be done with STDERR as well
and constants STD[OUT|ERR] are still usable
I understand that this question is ancient, but people trying to do what this question asks will likely end up here... Both of you.
If you are running under a particular environment...
Running under Linux (probably most other Unix like operating systems, untested)
Running via CLI (Untested on web servers)
You can actually close all of your file descriptors (yes all, which means it's probably best to do this at the very beginning of execution... for example just after a pcntl_fork() call to background the process in a daemon (which seems like the most common need for something like this)
fclose( STDIN ); // fd 3
fclose( STDERR); // fd 2
fclose( STDOUT ); // fd 1
And then re-open the file descriptors, assigning them to a variable that will not fall out of scope and thus be garbage collected. Because Linux will predictably open them in the proper order.
$kept_in_scope_variable_fd1 = fopen(...); // fd 1
$kept_in_scope_variable_fd2 = fopen(...); // fd 2
$kept_in_scope_variable_fd3 = fopen( '/dev/null', ... ); // fd 3
You can use whatever files or devices you want for this. I gave /dev/null as the example for STDIN (fd3) because that's probably the most common case for this kind of code.
Once this is done you should be able to do normal things like echo, print_r, var_dump, etc without specifically needing to write to a file with a function. Which is useful when you're trying to background code that you do not want to, or aren't able to, rewrite to be file-pointer-output-friendly.
YMMV for other environments and things like having other FD's open, etc. My advice is to start with a small test script to prove that it works, or doesn't, in your environment and then move on to integration from there.
Good luck.
Here is an ugly solution that was useful for a problem I had (need to debug).
if(file_get_contents("out.txt") != "in progress")
{
file_put_contents("out.txt","in progress");
$content = file_get_contents('http://'.$_SERVER['HTTP_HOST'].$_SERVER['REQUEST_URI']);
file_put_contents("out.txt",$content);
}
The main drawback of that is that you'd better not to use the $_POST variables.
But you dont have to put it in the very beggining.

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