This guide explains how you can create an SMS service
using PHP that processes incoming SMS messages. It explains the
configuration of the SMS gateway and gives you instructions on
how you can process SMS messages in your PHP script.
The guide is aimed at software developers who are familiar with the
PHP programming language.
Introduction
PHP is usually used in web development environments. It is quite common
that a PHP script is called when a webpage is requested. Often this PHP script
is interacting with a database, such as MySQL to store and retrieve information
to be displayed on the website. The solution I am going to present here for
SMS messaging assumes you are hosting your PHP script on a webserver and you
prefer to receive SMS messages over HTTP request. If your PHP script is
using a database server for data storage, you might want to consider to setup
an SQL SMS Gateway for sending and receiving SMS messages. This
topic is covered in detail in the following guide:
SQL - SMS Gateway. This guide
gives instructions on how you can create an HTTP - SMS Gateway configuration
based on Ozeki NG SMS Gateway (Figure 1).
Figure 1 - How to receive an SMS from a website
Getting started
To start first you need to setup a hosting environment for your PHP script.
This includes the installation of the following components:
1.) Apache webserver
2.) PHP programming language
You also need to download and install Ozeki NG SMS Gateway!
After these components are installed, you will have a WWWRoot directory
that can be used to host PHP scripts. I assume you have configured Apache
to use "C:\www\" as the WWWRoot directory.
Testing your hosting environment
To test your hosting environment save the smsresponse.php PHP script
inC:\www\.
C:\www\smsresponse.php
<?php
$sender = $_GET['sender'];
$message = $_GET['msgdata'];
if ($sender!='') {
#
# Save incoming messages
#
$fp = fopen("receivelog.txt","a");
fputs($fp,"$sender $message\n");
fclose($fp);
#
# Return a response SMS message
#
$responsetext = "Thank you for the message!";
echo "{SMS:TEXT}{}{}{".$sender."}{".$responsetext."}";
} else {
echo "The PHP script is ready for accepting messages";
}
?>
Figure 2 - Source code of the PHP SMS receiver script
If you have saved the smsresponse.php file into your WWWRoot directory (C:\www)
you can test your script by using Internet Explorer. In Internet Explorer
you should open the URL pointing to your script. This URL is:
http://127.0.0.1/smsresponse.php
If your hosting environment is working and your PHP script is successfully
installed, you should see the following text: "The PHP script is ready for
accepting messages" (Figure 3.). This text is displayed in your browser.
Figure 3 - Testing the SMS receiver script in a browser
Configuring the SMS Gateway
Once your PHP script is ready for accepting incoming messages, you
should install and configure the SMS gateway. The SMS gateway will pass
incoming SMS messages to your PHP script using HTTP requests, this is
why we call this configuration HTTP-SMS Gateway configuration. To install
the SMS gateway you should perform the following steps:
After these steps are complete you can configure the SMS gateway to pass
incoming messages to the smsresponse.php PHP script. Incoming messages
will be forwarded to this PHP script using the HTTP GET method. The SMS Gateway
has an HTTPClient user that has the functionality we need. To get the HTTPClient
user to work for us we need to add it to our configuration. To do this
click on "Add" in the top right hand corner of the "Users and Applications" panel
of the SMS Gateway management console (Figure 4.).
Figure 4 - adding a new user.
This will bring up the "Add user or application" form. In this form you should
select the HTTP Client user and click on install (Figure 5).
Figure 5 - installing the HTTPClient user
To install the HTTPClient user you need to provide a unique user name. I recommend
to use "myphp" for this (Figure 6). Ozeki NG SMS Gateway allows you to configure
many HTTP client users. This is useful if you wish to use many different PHP
applications. You can configure one HTTP Client user for every PHP application
that is responsible for providing SMS services and you can use the
inbound routing
configuration to decide which messages should be received by which user.
Figure 6 - providing a unique name for the HTTPClient user
After the HTTPClient user has been created, you should configure the URL that
points to your PHP application (Figure 7). In our case this will be:
Please note that this URL contains keywords, such
as $originator, $recipient, $messagedata, etc...
These keywords will be replaced in the URL to the actual values of the
incoming messages before the URL is called to forward the message to
your PHP script. A complete list of keywords you can use is listed in the
HTTP Client user documentation.
Figure 7 - URL pointing to the PHP application
After setting the URL your system is ready to operate.
Testing your configuration
If you wish to test your configuration, the first thing you want to do is
to see the HTTP communication between the SMS Gateway and your PHP script.
To see this communication, you should enable "low level communication logging"
in the HTTPClient user configuration form. You can enable low level communication
logging by clicking on the "Logging" tab (Figure 8) of the form and checking
the "Log low level communication" checkbox.
Figure 8 - Enabling low level communication logging
After the low level communication logging is enabled you are ready to send
your first SMS message. When you send your SMS message to the system
from your mobile phone, the GSM Modem connection of the SMS gateway will receive
it (Figure 9). The GSM Modem connection will forward the message
to the inbound routing table. The inbound routing table will find the
matching inbound routing rule and will forward the SMS to the HTTPClient user.
The final step is performed by the HTTPClient user who will forward the
message to the smsresponse.php script using an HTTP GET request.
Figure 9 - Testing the pipeline
Figure 9 - Testing the pipeline
Checking the logs
Since you have enabled low level communication logging in the HTTPClient user
configuration form you can use the event viewer of the SMS Gateway to see
the HTTP request that was used to pass the message to your PHP script. The
event viewer also displays the HTTP response, which is useful if you are
looking for errors. The event viewer can be opened in two ways: You can use
the menu (Figure 10) or you can click on the "events" link in the user data sheet.
