Send command from PHP to running Python script

Question

At the moment I am planning a project with the RaspberryPi. Therefore I plan to write a script in Python that runs in the background and reacts to user input (buttons, rotary knob, etc.). Additional to the Python script I have a webinterface with PHP under it. The goal is to lat the user change settings through the webinterface and pass the changed variables (e.g. a Twitter username) to the Python script so it can update its variables.

Unfortunatelly I have no idea how to pass data to the running Python script. Do you have any ideas?

• Bob: The easiest way would probably be to have it write to a common file that the python script will constantly poll and grab information from. Alternatively you could probably redirect stdin to that file. This is assuming that your script will be constantly running as you suggest. Probably best to do this with Threading. I'd start there.

Answer 1

store modifiable settigns in a json file

settings.json

{"twitter_user": "bob"} 

before doing something load your json settings

myscript.py

import json
def do_something():
 settings = json.load(open("settings.json"))
 print settings["twitter_user"]

update your settings.json via php as needed

myscript.php

function change_twitter_user($uname){
 $settings = json_decode(file_get_contents($file));
 $settings["twitter_user"] = $uname
 file_put_contents("/path/to/settings.json",json_encode($settings ));
}

thats probably the easiest way to do it

(although you do know that python has some very nice web stuff also right?)

• Georg: I also thought about outsourcing the settings into a file, but I thought it is verry hacky to access a file everytime before I fetch the new Tweets... I never used webstuff in Python (acually I like Twig and bootstrap in PHP) are there some nice examples/tutorials?
• Joran Beasley: naw just check it when your idle .... if they changed it a fraction of a second before they hit the button to get tweets or whatever who cares ... just watch the file timestamp in your onIdle loop or whatever ... another option would be running a socket server in python and sending socket messages from php ... but you are adding alot of unnecessary complications
• Georg: OK I think I will stick to the file method. It's easy and doeas what I need. Thank you