On Friday, Jeffrey showed me Nelson’s new Google AdWords API service. Google has now exposed all parts of the AdWords program via a SOAP Web service API.

Unfortunately, SOAP and PHP still aren’t the best of friends. True, Nelson has graciously provided us with some NuSOAP PHP example code. However, when I viewed it, I immediately barfed all over myself. Gross!

Any SOAP library that requires you to use angle-brackets is missing the point of SOAP. To be fair, I’d never used NuSOAP before today, so maybe it’s possible to rewrite the code to be more elegant, but I couldn’t stomach trying.

I mean, come on. This is no way to set a SOAP header:

// Set up the authentication headers
$email = "<email>youremail@your company.com</email>";
$password = "<password>yourpassword</password>";
$userAgent = "<useragent>YOURCOMPANY -- PHP KeywordReport Demo</useragent>";
$token = "<token>developer_token_here_</token>";
$header = $email . $password . $userAgent . $token;

And comments like this?

// With nusoap, you need to include XML with the parameters
$keyword0 = "<text>flowers</text>";
$keyword1 = "<text>chocolates</text>";
$otherinfo = "<maxCpc>50000</maxCpc><type>Broad</type>";

I need to include XML?!? Forget it.

So, out of the spirit of being a good citizen, I rewrote the "Estimating traffic for a keyword" example using PHP 5’s ext/soap extension.

// Connect to the WSDL for the TrafficEstimatorService
$wsdl = "https://adwords.google.com/api/adwords/v2/TrafficEstimatorService?wsdl";
$client = new SOAPClient($wsdl));

// Create the SOAP Headers for authentication
$ns = 'https://adwords.google.com/api/adwords/v2';
$email = new SOAPHeader($ns, 'email', 'adam@trachtenberg.com');
$password = new SOAPHeader($ns, 'password', 'XXX');
$useragent = new SOAPHeader($ns, 'useragent', 'Blah, blah');
$token = new SOAPHeader($ns, 'token', 'XXX');
$headers = array($email, $password, $useragent, $token);

// The Keywords we're interested in
$keywords = array(array('text' => 'php', 'maxCpc' => 100000, 'type'=> 'Broad'),
                  array('text' => 'mysql', 'maxCpc' => 250000, 'type' => 'Broad'),
                 );
try {
  // Make the request to estimate the keywords
  $response = $client->__soapCall('estimateKeywordList',  array($keywords), null, $headers);

  // If we got this far, $response contains the estimates
  $count = count($response->estimateKeywordListReturn);
  echo "<P>There are " . $count . " elements in the response array.";

  // A single  response is returned as an array of field values.
  // Multiple responses are returned as an array of arrays.
  if (! is_array($response->estimateKeywordListReturn)) {
    $response->estimateKeywordListReturn = array($response->estimateKeywordListReturn);
  }

  for ($i = 0; $i < $count; $i++) {
    // Need to get the keyword text out of $keywords array
    // because the keywordEstimate doesn't know the keyword text
    echo "<H3>" . $keywords[$i]['text'] . "</H3>";
    printResults($response->estimateKeywordListReturn[$i]);
  }    
} catch (Exception $e) {
  // Barf
  print $e;
}

function printResults ($estimate) {
  echo "<blockquote>cpc " . $estimate->cpc; 
  echo "<br>clicks " . $estimate->ctr * $estimate->impressions;
  echo "<br>ctr " . $estimate->ctr; 
  echo "<br>impressions " . $estimate->impressions;
  echo "<br>notShown " . $estimate->notShownPerDay;
  echo "<br>position " . $estimate->avgPosition;
  echo "</blockquote>";
}

No more XML. Still a little kludgy because of the SOAP headers, but overall much nicer.

In the process, I found a bug involving SOAPHeader objects when you don’t want your data to live inside a namespace, but I managed to work around that by placing them inside the AdWords API namespace.

I was also thrown a little bit by the example, which places the keywords inside a “KeywordRequest” element, when the WSDL seems to want a “keywordRequests” element. (Note different capitalization and pluralization.) This had me running down all sorts of dead ends and blaming the WSDL parser.

Last, I’m confused why the server doesn’t return the keywords back to me. Forcing me to map the input and the output is a little kludgy.

Overall, however, this looks quite nice. I plan on playing around with it more later, and I’m sure our eBay API Affiliates are having a field day.