Creating a simple SOAP server

As with the SOAP client, we can use the PHP SOAP extension to implement a SOAP server. The most difficult part of the implementation will be generating the WSDL from the API class. We do not cover that process here as there are a number of good WSDL generators available.

How to do it...

First, you need an API that will be handled by the SOAP server. For this example, we define an Application\Web\Soap\ProspectsApi class that allows us to create, read, update, and delete the prospects table:

namespace Application\Web\Soap;
use PDO;
class ProspectsApi
{
  protected $registerKeys;
  protected $pdo;
        
  public function __construct($pdo, $registeredKeys)
  {
    $this->pdo = $pdo;
    $this->registeredKeys = $registeredKeys;
  }
}

We then define methods that correspond to create, read, update, and delete. In this example, the methods are named put(), get(), post(), and delete(). These, in turn, call methods that generate SQL requests that are executed from a PDO instance. An example for get() is as follows:

public function get(array $request, array $response)
{
  if (!$this->authenticate($request)) return FALSE;
  $result = array();
  $id = $request[self::ID_FIELD] ?? 0;
  $email = $request[self::EMAIL_FIELD] ?? 0;
  if ($id > 0) {
      $result = $this->fetchById($id);  
      $response[self::ID_FIELD] = $id;
  } elseif ($email) {
      $result = $this->fetchByEmail($email);
      $response[self::ID_FIELD] = $result[self::ID_FIELD] ?? 0;
  } else {
      $limit = $request[self::LIMIT_FIELD] 
        ?? self::DEFAULT_LIMIT;
      $offset = $request[self::OFFSET_FIELD] 
        ?? self::DEFAULT_OFFSET;
      $result = [];
      foreach ($this->fetchAll($limit, $offset) as $row) {
        $result[] = $row;
      }
  }
  $response = $this->processResponse(
    $result, $response, self::SUCCESS, self::ERROR);
    return $response;
  }

  protected function processResponse($result, $response, 
                                     $success_code, $error_code)
  {
    if ($result) {
        $response['data'] = $result;
        $response['code'] = $success_code;
        $response['status'] = self::STATUS_200;
    } else {
        $response['data'] = FALSE;
        $response['code'] = self::ERROR_NOT_FOUND;
        $response['status'] = self::STATUS_500;
    }
    return $response;
  }

You can then generate a WSDL from your API. There are quite a few PHP-based WSDL generators available (see the There's more... section). Most require that you add phpDocumentor tags before the methods that will be published. In our example, the two arguments are both arrays. Here is the full WSDL for the API discussed earlier:

<?xml version="1.0" encoding="UTF-8"?>
  <wsdl:definitions xmlns:tns="php7cookbook" targetNamespace="php7cookbook" xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/" xmlns:s="http://www.w3.org/2001/XMLSchema" xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/" xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/">
  <wsdl:message name="getSoapIn">
    <wsdl:part name="request" type="tns:array" />
    <wsdl:part name="response" type="tns:array" />
  </wsdl:message>
  <wsdl:message name="getSoapOut">
    <wsdl:part name="return" type="tns:array" />
  </wsdl:message>
  <!—some nodes removed to conserve space -->
  <wsdl:portType name="CustomerApiSoap">
  <!—some nodes removed to conserve space -->
  <wsdl:binding name="CustomerApiSoap" type="tns:CustomerApiSoap">
  <soap:binding transport="http://schemas.xmlsoap.org/soap/http" style="rpc" />
    <wsdl:operation name="get">
      <soap:operation soapAction="php7cookbook#get" />
        <wsdl:input>
          <soap:body use="encoded" encodingStyle= "http://schemas.xmlsoap.org/soap/encoding/" namespace="php7cookbook" parts="request response" />
        </wsdl:input>
        <wsdl:output>
          <soap:body use="encoded" encodingStyle= "http://schemas.xmlsoap.org/soap/encoding/" namespace="php7cookbook" parts="return" />
        </wsdl:output>
    </wsdl:operation>
  <!—some nodes removed to conserve space -->
  </wsdl:binding>
  <wsdl:service name="CustomerApi">
    <wsdl:port name="CustomerApiSoap" binding="tns:CustomerApiSoap">
    <soap:address location="http://localhost:8080/" />
    </wsdl:port>
  </wsdl:service>
  </wsdl:definitions>

Next, create a chap_07_simple_soap_server.php file, which will execute the SOAP server. Start by defining the location of the WSDL and any other necessary files (in this case, one for database configuration). If the wsdl parameter is set, deliver the WSDL rather than attempting to process the request. In this example, we use a simple API key to authenticate requests. We then create a SOAP server instance, assign an instance of our API class, and run handle():

<?php
define('DB_CONFIG_FILE', '/../config/db.config.php');
define('WSDL_FILENAME', __DIR__ . '/chap_07_wsdl.xml');
      
if (isset($_GET['wsdl'])) {
    readfile(WSDL_FILENAME);
    exit;
}
$apiKey = include __DIR__ . '/api_key.php';
require __DIR__ . '/../Application/Web/Soap/ProspectsApi.php';
require __DIR__ . '/../Application/Database/Connection.php';
use Application\Database\Connection;
use Application\Web\Soap\ProspectsApi;
$connection = new Application\Database\Connection(
  include __DIR__ . DB_CONFIG_FILE);
$api = new Application\Web\Soap\ProspectsApi(
  $connection->pdo, [$apiKey]);
$server = new SoapServer(WSDL_FILENAME);
$server->setObject($api);
echo $server->handle();

Note

Depending on the settings for your php.ini file, you may need to disable the WSDL cache, as follows:

ini_set('soap.wsdl_cache_enabled', 0);

If you have problems with incoming POST data, you can adjust this parameter as follows:

ini_set('always_populate_raw_post_data', -1);

How it works...

You can easily test this recipe by first creating your target API class, and then generating a WSDL. You can then use the built-in PHP webserver to deliver the SOAP service with this command:

php -S localhost:8080 chap_07_simple_soap_server.php

You can then use the SOAP client discussed in the previous recipe to make a call to test the SOAP service:

<?php
define('WSDL_URL', 'http://localhost:8080?wsdl=1');
$clientKey = include __DIR__ . '/api_key.php';
try {
  $client = new SoapClient(WSDL_URL);
  $response = [];
  $email = some_email_generated_by_test;
  $email = 'test5393@unlikelysource.com';
  echo "\nGet Prospect Info for Email: " . $email . "\n";
  $request = ['token' => $clientKey, 'email' => $email];
  $result = $client->get($request,$response);
  var_dump($result);
  
} catch (SoapFault $e) {
  echo 'ERROR' . PHP_EOL;
  echo $e->getMessage() . PHP_EOL;
} catch (Throwable $e) {
  echo 'ERROR' . PHP_EOL;
  echo $e->getMessage() . PHP_EOL;
} finally {
  echo $client->__getLastResponse() . PHP_EOL;
}

Here is the output for email address test5393@unlikelysource.com:

Table of Contents for
PHP 7: Real World Application Development

Creating a simple SOAP server

How to do it...

Note

How it works...

See also

Table of Contents for PHP 7: Real World Application Development

Creating a simple SOAP server

How to do it...

Note

How it works...

See also

Table of Contents for
PHP 7: Real World Application Development