Question

I tested Magento’s SOAP API using soapUI. I successfully logged in and got a login hash.
Then I tried to retrieve a list of products and this worked fine.

This was on a Linux server using the latest version of Apache, mySQL and PHP.

I then created a backup of Magento and the database. I wanted to create a test environment on a Lion server using a MAMP stack. The Magento backup seems to work fine, but the SOAP API doesn’t.

Again I used soapUI to get a login hash and tried to retrieve all products. But now the response seems to be incomplete:

<?xml version="1.0" encoding="UTF-8"?>
<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" xmlns:ns1="urn:Magento">
<SOAP-ENV:Body>
<ns1:catalogProductListResponseParam>
<result>
<complexObjectArray>
<product_id>7167</product_id>
<sku>000140</sku>
... etc ...
<complexObjectArray>34</complexObjectArray>
</category_ids>
<website_ids>
<complexObjectArray>1</complexObjectArray>
</website_ids>
</complexObjectArray>
<complexObjectArray>
<product

Why is the reponse incomplete under Lion/MAMP?

Answer 1

I had a problem with incomplete SOAP XML responses once.

The setup was like this:

• Linux server
• Magento CE 1.5.1.0
• Usage of SOAP v2 with WS-I compliance enabled
• Call of sales_order.info

Even if you use a different Magento version and a different SOAP call, you may suffer from a similar bug as I did. The problem was that the HTTP Content-Length header was calculated incorrectly for responses > 8000 bytes.

How to verify if you are affected by this bug:

1. Execute a call which delivers a short response (e.g. “catalog_category.info” with just a single store-view and only few attributes). If the XML is complete, check if the response has a length <= 8000 bytes.
2. Copy the file app/code/core/Mage/Api/Model/Server/Wsi/Adapter/Soap.php to your app/code/local folder and edit the run() method. If you use the “wsdl” parameter in your SOAP URL, edit the first part of the “if” structure, otherwise edit the “else” part.

As the second way is the more accurate way to do it, I’ll go with this.

1. Open the file and search for the ->setBody() method call. As you can see, there is some search/replace magic going on.

2. Write the result of the search/replace operations into a variable and log it for further examination. The code may look like this:

   public function run()
   {
       $apiConfigCharset = Mage::getStoreConfig("api/config/charset");
   
       if ($this->getController()->getRequest()->getParam('wsdl') !== null) {
           /* don't modify the first part ... */
       } else {
           try {
               $this->_instantiateServer();
   
               $content = preg_replace(
                       '/(\>\<)/i',
                       ">\n<",
                       str_replace(
                               '<soap:operation soapAction=""></soap:operation>',
                               "<soap:operation soapAction=\"\" />\n",
                               str_replace(
                                       '<soap:body use="literal"></soap:body>',
                                       "<soap:body use=\"literal\" />\n",
                                       preg_replace(
                                           '/<\?xml version="([^\"]+)"([^\>]+)>/i',
                                           '<?xml version="$1" encoding="'.$apiConfigCharset.'"?>',
                                           $this->_soap->handle()
                                       )
                               )
                       )
               );
               Mage::log($content, null, 'soap.log');
               $this->getController()->getResponse()
                    ->clearHeaders()
                    ->setHeader('Content-Type','text/xml; charset='.$apiConfigCharset)
                    ->setBody($content);
           } catch( Zend_Soap_Server_Exception $e ) {
               $this->fault( $e->getCode(), $e->getMessage() );
           } catch( Exception $e ) {
               $this->fault( $e->getCode(), $e->getMessage() );
           }
       }
   }
   

3. Execute the SOAP API call and open var/log/soap.log in your Magento directory. If the XML is complete in the log file but not in your response, then the Content-Length header is the problem.

How to correct the Content-Length header

1. Stay in your copy of Mage_Api_Model_Server_Wsi_Adapter_Soap and add one line to the code we just modified:

   public function run()
   {
       $apiConfigCharset = Mage::getStoreConfig("api/config/charset");
   
       if ($this->getController()->getRequest()->getParam('wsdl') !== null) {
           /* don't modify the first part ... */
       } else {
           try {
               $this->_instantiateServer();
   
               $content = preg_replace(
                       '/(\>\<)/i',
                       ">\n<",
                       str_replace(
                               '<soap:operation soapAction=""></soap:operation>',
                               "<soap:operation soapAction=\"\" />\n",
                               str_replace(
                                       '<soap:body use="literal"></soap:body>',
                                       "<soap:body use=\"literal\" />\n",
                                       preg_replace(
                                           '/<\?xml version="([^\"]+)"([^\>]+)>/i',
                                           '<?xml version="$1" encoding="'.$apiConfigCharset.'"?>',
                                           $this->_soap->handle()
                                       )
                               )
                       )
               );
               Mage::log($content, null, 'soap.log');
               $this->getController()->getResponse()
                    ->clearHeaders()
                    ->setHeader('Content-Type','text/xml; charset='.$apiConfigCharset)
                    ->setHeader('Content-Length',strlen($content), true)
                    ->setBody($content);
           } catch( Zend_Soap_Server_Exception $e ) {
               $this->fault( $e->getCode(), $e->getMessage() );
           } catch( Exception $e ) {
               $this->fault( $e->getCode(), $e->getMessage() );
           }
       }
   }
   

   Note the line:

   ->setHeader('Content-Length',strlen($content), true)
   

   We calculate and set the Content-Length header. The third parameter, true, is important because it tells the framework to overwrite the existing Content-Length header.

2. If this works, remove the Mage::log() call and rewrite the code for use in your own extension.

If you ask why this problem occurs I can’t tell you exactly because I didn’t hunt the bug all the way down.

From what I saw, everything is fine as long as the XML response has a length <= 8000 bytes. If the response is longer than 8000 bytes and the XML consists of x lines, the response is truncated by x characters. It looks like it is a problem with the different carriage return codes and/or with encoding issues which lead to the wrong calculation of the response content length.