HelloServer.php - First SOAP Server Application

SOAP Web Service Tutorials - Herong's Tutorial Examples

∟HelloServer.php - First SOAP Server Application

This section describes a tutorial example of a complete SOAP application with both server and client programs.

Okay. Now let's build our first SOAP server. I want the first server to perform a very simple function of return a greeting string based on the input name. Here is my version called, HelloServer.php:

<?php 
# HelloServer.php
# Copyright (c) HerongYang.com. All Rights Reserved.
#
function hello($someone) { 
   return "Hello " . $someone . "!";
} 
   $server = new SoapServer(null, 
      array('uri' => "urn://www.herong.home/res"));
   $server->addFunction("hello"); 
   $server->handle(); 
?>

The sever application is ready. Note that:

This SOAP server application can not be used as a standalone SOAP server. It needs a HTTP server to receive SOAP requests, and a PHP runtime to act as a CGI to feed SOAP requests.
The "uri" value is just an unique identification, used as the namespace for the response message.

The HTTP server I will be using is the Apache Web server. It has already configured correctly to interface with PHP CGI. For details, see my other book: "Herong's Tutorial Notes on PHP". All I have to do is to move my server application to the Web server document directory:

C:\herong>copy HelloServer.php \local\apache\htdocs

To test my server application, I wrote this client application, HelloClient.php:

<?php 
# HelloClient.php
# Copyright (c) HerongYang.com. All Rights Reserved.
#
   $client = new SoapClient(null, array(
      'location' => "http://localhost/HelloServer.php",
      'uri'      => "urn://www.herong.home/req",
      'trace'    => 1 ));

   $return = $client->__soapCall("hello",array("world"));
   echo("\nReturning value of __soapCall() call: ".$return);

   echo("\nDumping request headers:\n" 
      .$client->__getLastRequestHeaders());

   echo("\nDumping request:\n".$client->__getLastRequest());

   echo("\nDumping response headers:\n"
      .$client->__getLastResponseHeaders());

   echo("\nDumping response:\n".$client->__getLastResponse());
?>

Make sure my Apache Web server is running. Then run HelloClient.php:

C:\herong>php HelloClient.php

Returning value of __soapCall() call: Hello world!

Dumping request headers:
POST /HelloServer.php HTTP/1.1
Host: localhost
Connection: Keep-Alive
User-Agent: PHP-SOAP/7.0.2
Content-Type: text/xml; charset=utf-8
SOAPAction: "urn://www.herong.home/req#hello"
Content-Length: 499

Dumping request:
<?xml version="1.0" encoding="UTF-8"?>
<SOAP-ENV:Envelope 
 xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" 
 xmlns:ns1="urn://www.herong.home/req" 
 xmlns:xsd="http://www.w3.org/2001/XMLSchema" 
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
 xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/" 
 SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">
 <SOAP-ENV:Body>
  <ns1:hello>
   <param0 xsi:type="xsd:string">world</param0>
  </ns1:hello>
 </SOAP-ENV:Body>
</SOAP-ENV:Envelope>

Dumping response headers:
HTTP/1.1 200 OK
Date: Sun, 02 Sep 2018 18:31:47 GMT
Server: Apache/2.4.12 (Win32) PHP/7.0.2
X-Powered-By: PHP/7.0.2
Content-Length: 522
Keep-Alive: timeout=5, max=100
Connection: Keep-Alive
Content-Type: text/xml; charset=utf-8

Dumping response:
<?xml version="1.0" encoding="UTF-8"?>
<SOAP-ENV:Envelope
 xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"
 xmlns:ns1="urn://www.herong.home/res"
 xmlns:xsd="http://www.w3.org/2001/XMLSchema"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/"
 SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">
 <SOAP-ENV:Body>
  <ns1:helloResponse>
   <return xsi:type="xsd:string">Hello world!</return>
  </ns1:helloResponse>
 </SOAP-ENV:Body>
</SOAP-ENV:Envelope>

Very exciting, right? Both server and client work nicely.

If you are interested in how the execution was carried out on the server, I have a simplified execution flow diagram on the server side:

                Apache      PHP (SOAP Extension)      HelloServer.php
    HTTP request  |
   -------------->|
    SOAP message  |
                  |  CGI   |      PHP CGI API
                  |------->|------------------------>|
                                                     | addFunction()
                                                     |
                                SOAP Extension API   | handle()
                           |<------------------------|
                           |
                           |    SOAP Extension API
                           |------------------------>|
                                SOAP Extension API   | hello()
                           |<------------------------|
                     CGI   |
                  |<-------|
    HTTP response | 
   <--------------| 
    SOAP message  |