Passing argument from PHP to Python not working - php

I have a python srcipt, called rainbow.py. I can run it optionally with an argument. From command line
python rainbow.py, python rainbow.py 4 works well. When I call this script from php I am unable to pass the argument.
I tried:
$argument=4;
exec("python rainbow.py 4");
exec("python rainbow.py $argument");
exec("python rainboy.py .$argument");
They make the code run like there's no valid argument. (I use duration=int(sys.argv[1] in my python code, the script needs to stop after a while, and when calling from php, always the default duration is active)
I tried
$argument="4"
too, did not work.
Can you tell me what's wrong?How can I pass this argument through? I am confident with python, but a total php newbie.
part of my php code:
$argument="2";
echo "printing line <br>";
exec("python rainbow.py $argument");//duration option does not work
part of my python code:
duration=10
try:
if sys.argv[1]!=None:
print "arg found!"
duration=int(sys.argv[1])
except: pass
print "duration:",duration
I cant see the duration printing out when calling python from php, but from LEDs I can cleary see the duration is always 10 seconds

I added sudo to the python call:
exec("sudo python rainbow.py $argument")
and it works now properly. Can someone tell me why?
The python script ran without it too, but without considering the argument.

Related

Echo Exec ("python filepath $variables") Not Working

I have a bit of backend code that is executed like so:
python filepath $inputvariable
This code prints out some data. As you can see in the screenshot below, when I run this code through terminal it works flawlessly, outputting the expected value:
CHI 110^*^Integrated Chinese Level 1 Part 1^*^https://www.amazon.com/Integrated-Chinese-Simplified-Characters-Textbook/dp/0887276385/ref=sr_1_1?ie=UTF8&qid=1466983577&sr=8-1&keywords=integrated+chinese^*^47.49
But I run into issues when I try to run the same code through php:
echo exec ("python /Users/USERNAME/Desktop/Exeter_Bookstore_Project/localserver/cont/Scripts/Python/serverside.py $classToSend");
This code returns a null value. At first I assumed that I wasn't passing variables through correctly, but echo $classToSend; yielded the correct variable. Then I tried having the php execute a hello world python script, but this also worked proving that the issue wasn't in my python interpreter. Then I thought that maybe the python script wasn't forwarding data quickly enough, but the helloworld.py still worked even with a time delay of 3 seconds.
Does anyone have any idea of what I might have done wrong, or do you need more information. Any help will be greatly appreciated.

How to run an external program in php

I have a program that I can run on my command line but I was wondering if I could actually get it to run in php. Basically my program would have a user insert a couple values to search for, then those values would be passed on into the program for it to run. Then I would want the result of the program to be displayed
I found a function called exec() but I didn't understand it at all so I was wondering if anyone else knows a way or can help me out!
exec() runs a command on the command line, just as you desire. You can capture the output of the command in an array named as the second argument.
For example:
exec("whoami", $output);
var_dump($output);
This runs linux's "whoami" command and captures the result in the array $output. The second line displays the contents of the array. Is that similar to what you want to do?

PHP variable into Python

I understand there are questions like mine already asked, but I can't figure this out even with the answers in those questions.
PHP:
<?php
$var1 = "hi";
$result = shell_exec('TestingStuff.py'.$var1);
?>
Python:
import sys
print(sys.argv[1])
Error received when running in Python:
IndexError: list index out of range
Both scripts are in the same folder.
Could someone please provide an answer with the code changes?
Error
If the Python script runs with no arguments at all, then that sys.argv[1] index is out of range.
Scripts
ExecPython.php
<?php
$var1 = "hi";
$result = shell_exec('TestingStuff.py ' . $var1);
echo "<pre>$result</pre>";
TestingStuff.py
import sys
if len(sys.argv) > 1:
print(sys.argv[1])
Demo
Explanation
We will start with the Python script. The goal is, that the script prints the first argument passed to it - without running into the "IndexError: list index out of range" error.
python TestingStuff.py 123 we want the output 123.
In Python the arguments passed to the script reside in sys.argv. It's a list. sys.argv[0] is always the script name itself (here TestingStuff.py). Using the example from above sys.argv[1] is now 123.
Handling the edge cases: "no argument" given.
python TestingStuff.py
This will result in an "IndexError: list index out of range" error, because you are trying to access a list element, which is not there. sys.argv[0] is the script name and sys.argv[1] is not set, but you are trying to print it and BAM goes the error. To avoid the error and only print the first argument, we need to make sure, that the list sys.argv contains more than one element (more than the script name). That's why i've added if len(sys.argv) > 1:.
That means: print the first argument only, if the list has more than 1 argument.
Now we can test the Python script standalone - with and without arguments.
And switch over to the PHP script.
The goal is to execute the Python script from PHP.
PHP provides several ways to execute a script, there are for instance exec(), passthru(), shell_exec(), system(). Here we are using shell_exec(). shell_exec() returns the output of the script or command we run with it.
In other words: if you run $result = shell_exec('php -v');, you'll get the PHP version lines in $result.
Here we are executing the Python script TestingStuff.py and add an argument, which is $var1. It's a string and added via concatenation to the string given to shell_exec(). The $result is echoed. I wrapped pre-tags around it, because i thought this is executed in the web/browser context. If you are using the scripts only on the CLI, you might drop the pre-tags.
Execution flow
the PHP script is executed
shell_exec() executes the Python script
shell_exec() returns the output of the Python script as $result
$result is printed by PHP via echo

php exec() and shell_exec()

I currently have a php page that my webserver serves. In order to display all the information I need to display on the page I need output from an external python script. So I have been using the exec() command of php to execute the python script and capture the output in an array of strings as follows:
$somequery = $_GET['query'];
$result = exec("python /var/www/html/query/myscript.py ".somequery."");
//some for loop to loop through entries in result and echo them.
However there are never any entries to be printed, yet when I run the command directly on the console of the server it will output correctly. I've tried echoing out the command on the webpage that I am executing and it's the correct command. The only thing I think it can be is that exec() doesn't stop the rest of the php program from executing before it finishes, leading to the loop i have printing out entries finding that $result is empty.
How can I ensure that exec() finishes executing before the rest of my php script? Are there maybe settings in php.ini that I would need to change? I'm not entirely sure.
EDIT: I've tried running and storing the output of shell_exec("echo hello"); and printing that output, it now prints. However, when running my command that takes a few seconds longer, the program never finishes executing it before going to the next line.
EDIT 2: I found my solution in the following post https://stackoverflow.com/a/6769624 My issue was with with the numpy python package I was using and I simply needed to comment out the line in /usr/lib64/python2.7/ctypes/init.py like the poster did and my script output correctly.
The correct way to get your shell output is like this:
exec("python /var/www/html/query/myscript.py ".somequery."", $result);
var_dump($result); //output should be in here
Give it a try.

PHP + Python - use PHP to pass string to Python program, and parse output

I have a great Python program on my webserver, which I want to use from inside my PHP web app.
Here's an example of the python command, and output as you would see it in terminal:
>>> print MBSP.parse('I ate pizza with a fork.')
I/PRP/I-NP/O/NP-SBJ-1/O/i
ate/VBD/I-VP/O/VP-1/A1/eat
pizza/NN/I-NP/O/NP-OBJ-1/O/pizza
with/IN/I-PP/B-PNP/O/P1/with
a/DT/I-NP/I-PNP/O/P1/a
fork/NN/I-NP/I-PNP/O/P1/fork ././O/O/O/O/.
You might recognize this as a typical POS tagger.
In any case, I'm confused about how to use a PHP-based web app to send this program a string like "I ate pizza with a fork", and somehow get the response back in a way that can be further parsed in PHP.
The idea is to use PHP to pass this text to the Python program, and then grab the response to be parsed by PHP by selecting certain types of words.
It seems like in PHP the usual suspects are popen() and proc_open(), but popen() is only for sending, or receiving information - not both? Is popen() able to give me access to this output (above) that I'm getting from the Python program? Or is there a better method? What about curl?
Here are all my options in terms of functions in PHP:
http://us.php.net/manual/en/function.proc-open.php
I'm lost on this, so thanks for your wise words of wisdom!
I use exec() for this purpose.
exec($command, $output);
print_r($output);
If you want to get a little heavier / fancier... give your python script an http (or xmlrpc) front end, and call that with a GET/POST. Might not be worth all that machinery though!
You could use popen(), and pass the input to your Python script as a command line argument, then read the output from the file descriptor popen gives you, or proc_open() if you want to interact bi-directionally with the Python script.
Example 1 in the proc_open manual: http://us.php.net/manual/en/function.proc-open.php gives an example of this.
If your Python needs it as stdin, you could try popening a command line:
echo "I ate pizza!"|my_python_progam.py
and just read the output. As usual, do proper input validation before sending it to the command-line.
Something like this would work
$command = '/usr/bin/python2.7 /home/a4337/Desktop/script.py'
$pid = popen('$command',r)
........
........
.........
pclose($pid)

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