how to read an http get request from a php server

Question

I have a client in php who make an http get request to a server. that's the code:

client

<?php

function xml_post($xml_request)
{
    $url="http://localhost/malakies/server.php?xml=" . urlencode($xml_request);
    $ch=curl_init();

    curl_setopt($ch,CURLOPT_URL,$url);
    curl_setopt($ch,CURLOPT_RETURNTRANSFER,1);
    $result=curl_exec($ch);

    if (curl_errno($ch)){
    $ERR .= "cURL ERROR: ".curl_errno($ch).": ".curl_error($ch)."\n";
    }

    return $result;
}

$result=xml_post("Send sth");
echo $result; ?>

and the server code:

<?php
$postdata = $_GET['xml'];
echo $postdata; ?>

All work perfect. But i have a question that it may be a rookie one:) I want in the server side to have sth like a listener that listens when an http get request have come and do sth with this request. i don't know if http request is the technique that gives me an option like this.. i want sth like that:

while(http request hasn't come yet) 
   just wait;
do sth with the http request.

Thank you in advance.

It is a strange request. In a sense, your webserver already does this for you. It triggers your PHP script when the request comes in. Is that insufficient in some way? — Jeff Parker
– Jeff Parker, Commented Jul 8, 2011 at 14:02
You have Apache doing this job (listening to incoming HTTP requests). Or you want to keep the connection with the client opened for long time periods? What is the aim of this? — Gedrox
– Gedrox, Commented Jul 8, 2011 at 14:03

usoban · Accepted Answer · 2011-07-08 14:07:29Z

1

PHP script is ran automatically for each separate request. So actually PHP/Apache is already doing what you're asking for.

Maybe this is a bit confusing if you're coming from different programming language (like Java) where you typically have an event loop waiting for new connection.

On the other hand, maybe you had a specific situation in your mind. Please explain your requirements further if that's the case ...

answered Jul 8, 2011 at 14:07

usoban

5,47830 silver badges42 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Christos Mitsis Over a year ago

Ok to explain.. Like java you have for example an event function like click one that is triggered when an element be clicked. In similar way i would like a function like this in php which will be triggered when an http request comes. Assume that client and server are two web sites. if i delete the command "echo $result;" from the client code i want when i open the "server" site to see the string "send sth". if i have two tabs open in a browser (clent and server) when i refresh the client i want to see the string "send sth" in the server side not in the client.

usoban Over a year ago

Well the situation you described matches my answer. PHP module runs requested script for each request seperately. That means if you run the client code twice, server code will also be ran twice (since you're doing a request from the client twice). If your server code wants to store information about the client (e.g. you want to store the data client has sent), you use sessions. Session is typically identified via cookie that is stored at client (normally browser), but since you're using CURL, you probably are gonna need to use cookiejar for sessions (php.net/manual/en/book.curl.php)

Albert Hendriks · Accepted Answer · 2011-07-14 18:01:18Z

0

Because your url "ends" in server.php, you need to place a file on your server named "server.php". If your curl script returns a 404 error, you don't have the file at the right location. Where you need to place the file, depends on the operating system. On Linux, this COULD be /var/www/. So you need to find out what your "document root" is. There you would create a subdir malakies. In the Linux example this would be /var/www/malakies/server.php. PHP will then execute the script inside your file when the request comes in. The data you pass will be placed in an associative array named $_GET. I suggest the following contents for server.php:

<?php
echo "Have a first line so you see something even when no data is passed\n";
var_dump($_GET['xml']);
?>

xml_post in you curl function will then return (disregard the colors)

Have a first line so you see something even when no data is passed
Send sth

If it's not working, what's the error code you get?

I assumed that you have apache installed and that you want to catch the request with PHP.

edited Jul 14, 2011 at 18:01

answered Jul 14, 2011 at 17:48

Albert Hendriks

2,2124 gold badges31 silver badges51 bronze badges

1 Comment

Christos Mitsis Over a year ago

I changed my technique with sockets. I found them really useful for the purpose of my experiment. I will check out your solutions for http requests! ty!

Collectives™ on Stack Overflow

how to read an http get request from a php server

2 Answers 2

2 Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related