XML Reference Guide

Mar 14, 2003

␡

⎙ Print

< Back Page 260 of 278 Next >

At this point, we've accomplished the first step in our mashup project, which was to create an application out of a web API. Of course, the application itself isn't terribly useful; all we can really do is display a map and add markers to it. We can also center the map, but it's a rather arbitrary process, as we're just centering on the location in which the user clicks. What we're going to do now is look at a second API, which we will ultimately combine with the first for our mashup. (In fact, we are going to integrate a third service as well, but we'll get to that in the next section.)

The second service we're going to integrate is itself a combination of different services. The Indeed job search site includes listings from many different sources, such as Dice.com, Monster.com, and even classified ads. You can go to their site and do a search, or you can use their web API, as we are going to do.

The Indeed API requires you to have a "key", which entitles you to 500 free searches a day. I've included my key in the application; if you have trouble using it, go to the site and get your own key. It's free, and you just have to plug it into the form.

The API uses REST, which means it's going to be extremely simple for us to use the data with Ajax. What we're going to do is use a form to collect the information, use the information from the form to create the URL to which were going to submit the request, receive the information, and then analyze and display it in a div. Later, we'll plot it out on the map.

The first step is to create the actual form:

<html>
<head><title>Indeed Jobs</title></head>
<body>

<div id="jobs"></div>

    <script src="https://maps.google.com/maps?file=api&v=1&key=ABQIAAAAZBHmEX-pUz26mphjVq6DsBTENWKvAmocgv4W7AlW6y4wknzddxSNvlGbpUPwhclnFklpZ8Ty4jkvSw" type="text/javascript"></script>

<script type="text/javascript">

</script>

<h1>Find a job</h1>

<form action="" onsubmit="sendRequest(this); return false;">
<table>
<tr><td>Indeed key:</td><td><input type="text" name="key" value="8ddefca067a351d2f4dd3db4c2d90ce5" /></td></tr>
<tr><td>What kind of job:</td><td><input type="text" name="q" value="" /></td></tr>

<tr><td>Where you want it:</td><td><input type="text" name="l" value="" /></td></tr>
<tr><td colspan="2"><input type="submit" value="Send" /></td></tr>
</table>

</form>
</body>
</html>

You may have noticed that we are including the script that contains the Google Maps API. This is not a mistake. In fact, as I mentioned earlier, the API includes several pieces that are not necessarily visual, but are extremely handy. One of those is a version of the XmlHttpRequest object, which is going to vastly simplify our lives when we start creating Ajax requests.

In the meantime, notice that we have a generic form, with the exception of the fact that rather than submitting it to an actual URL, the browser executes the sendRequest() script. By returning false for the onsubmit attribute, we guarantee that the form itself will never actually be submitted, so the user remains on this page.

The next step is to build the request:

...
<script type="text/javascript">

function sendRequest(theForm){
   document.getElementById("jobs").innerHTML = "Sending...";

   var url = "http://api.indeed.com/apisearch?";
   url = url + "key="+URLencode(theForm.elements["key"].value);
   url = url + "&q="+URLencode(theForm.elements["q"].value);
   url = url + "&l="+URLencode(theForm.elements["l"].value);
   url = url + "&filter=1&latlong=1";

   getJobs(url);

}

function URLencode(sStr) {
   return escape(sStr).replace(/\+/g, '%2B').replace(/\"/g,'%22').replace(/\'/g, '%27').replace(/\//g,'%2F');
}

</script>

<h1>Find a job</h1>
<form action="" onsubmit="sendRequest(this); return false;">
...

The process of building the URL is pretty straightforward. All we're doing here is pulling out specific values from the form, and using the URLencode function we first used with our timesheet project to make sure the data gets passed properly. The last two parameters are needed by the Indeed API to filter out duplicate results, and to tell the system to return a latitude and longitude value for each job. Remember, Google Maps only works with these coordinates, as opposed to street addresses.

If you have difficulty getting latitude and longitude values with a request like this, try using a value of true rather than a value of 1. During the writing of this article, the value did change from one to the other and back again, even though the documentation specifies a value of 1. Also, the request will return a maximum of 10 jobs, but if you like, you can create requests that start on subsequent "pages", say with a "next" and "previous" link, by adding the start value and specifying the number of records to offset.

Finally, we'll call the function that actually requests the jobs from the server.

Now, before we can move on, and we do need to once again visit one of the problems of using Ajax in the browser: cross domain restrictions. As before, we are running up against the problem that a browser may not request an HTTP stream from any server but the one from which the page was downloaded. So to solve that problem, we will once again use our proxy script:

<?

$filepath = $_GET['url'];     
$file_contents = file_get_contents($filepath);    
print($file_contents);  

?>

This PHP script doesn't actually do anything major. All it does is retrieve the contents of any the request, and then print it back out to the browser, or in this case, to the JavaScript request. Save it on your server as proxy.php. (Feel free to implement this in your own favorite language, of course! I've set up a page for different versions of this proxy script. Feel free to check for your language, or contribute your own!)

All of this means that if we have for for which we create the Indeed URL of:

http://api.indeed.com/apisearch?key=8ddefca067a351d2f4dd3db4c2d90ce5&q=java%20developer&l=32618&filter=1&latlong=1

We'll wind up with the result something like:

<?xml version="1.0" encoding="UTF-8" ?>
<response>
    <query>java developer</query>
    <location>32618</location>

    <dupefilter>true</dupefilter>
    <highlight>true</highlight>
    <totalresults>7</totalresults>
    <start>1</start>

    <end>7</end>
    <results>
       
        <result>
            <jobtitle>Web Application Developer/.Net Programmer</jobtitle>
            <company>Netsource Technologies</company>

            <city>Ocala</city>
            <state>FL</state>
            <country>US</country>
            <source>Monster</source>

            <date>Sat, 18 Mar 2006 02:08:22 GMT</date>
            <snippet><b>Developer</b>/.Net Programmer for our Ocala office. We are not looking for contractors, outsourced <b>developers</b>... Experience:   HTML, <b>Java</b> Script, and VB Script...</snippet>

            <url>http://www.indeed.com/rc/clk?cd=2e3Dk3g7xxVxZ0mN_gBdQvskd-U__xb7ROgfdt02u6F9tntlrf1LYeq55qzkHOByiPAM3dOdPcuZWEFR7Ft0xfGZ_aFA5TL5Ns3aCDfaoRxfzCp2kgBRgLA-pHxERbd4&qd=RnZhMybXSk4M3QtTVGXWoaz1wh_2ttdZVIqQ7WHhgHEIK4tQ9bdscM__Azf7N3BcSkE8i4JV7vE0q94XalpwDFbAR4cH_XVRVgWS9PV3xEE&rd=i9i5wxAjTH4MK5Gz0qo8FA</url>
            
            <latitude>29.187704</latitude>
            <longitude>-82.130615</longitude>

            
        </result>

        <result>
            <jobtitle>Web Application Developer/.Net Programmer</jobtitle>
            <company>One Stop</company>

            <city>Ocala</city>
            <state>FL</state>
            <country>US</country>
            <source>One Stop</source>

            <date>Wed, 15 Mar 2006 23:07:49 GMT</date>
            <snippet><b>Developer</b>/.Net Programmer for our Ocala office. We are not looking for contractors, outsourced <b>developers</b>... Experience: . HTML, <b>Java</b> Script, and VB Script...</snippet>

            <url>http://www.indeed.com/rc/clk?cd=YgHkxiP8EhstZuuDZHgl0PZ4GY_b826Pi2c0dt_079JoCYFfud4jUNXYOUmh99KuT3eEURrr2CzhRTdQEkPnV74YFkgGEJJnrHTdqupvW3T7MqfLqJIDFUzCTAU2bNyx8S6cmrvpP58uRPKGeE98JXmCIIh4M09Ddxc5x--uIgrBYVE3QZKHduudyQ-u1cS0yg0GT77yBHoK-FGuXzfAdQ&qd=RnZhMybXSk4M3QtTVGXWoaz1wh_2ttdZVIqQ7WHhgHEIK4tQ9bdscM__Azf7N3BcSkE8i4JV7vE0q94XalpwDFbAR4cH_XVRVgWS9PV3xEE&rd=TEF42SAR5bfxLIqpAiYczw</url>
            
            <latitude>29.187704</latitude>
            <longitude>-82.130615</longitude>

            
        </result>
...
    </results>
</response>

Now let's look at actually retrieving the data:

...
   getJobs(url);

}

function getJobs(theUrl){

   document.getElementById("jobs").innerHTML = "Sending...";

   var request = GXmlHttp.create();
   request.open('GET', 'proxy.php?url='+URLencode(theUrl), true);
   request.send(null);

}

function URLencode(sStr) {
   return escape(sStr).replace(/\+/g, '%2B').replace(/\"/g,'%22').replace(/\'/g, '%27').replace(/\//g,'%2F');
}
...

Once we set the content of the jobs div so the user knows something is actually happening, the first step is to create an instance of the GXmlHttp object. This is from the Google Maps API, and is actually a cross-browser version of the XmlHttpRequest object. (If you remember from our discussion on Ajax, we normally would have to create the object differently depending on what browser we were using.) Once we have the object, we can open the request, feeding it the URL for the request itself, which is actually the proxy and a URL encoded version of the Indeed API request. We can then send that request. Since we are using get, all of the information is in the URL, so there is no data in the actual request.

Of course, right now we are not actually doing anything with the data when we get it.

In order to do something with the data, we have to know when it arrives. We can do that by checking the "ready state" when it changes:

...
   getJobs(url);

}

function getJobs(theUrl){

   document.getElementById("jobs").innerHTML = "Sending...";

   var request = GXmlHttp.create();
   request.open('GET', 'proxy.php?url='+URLencode(theUrl), true);
   request.onreadystatechange = function() {
      if (request.readyState == 4) {
	   //DO SOMETHING
      }
   };
request.send(null);
}
...

In some cases, we build applications that give the user progress reports, but because we've already adjusted the results div to show that we are doing something, we'll just let that sit until the data arrives. We will know that has happened when the "ready state" is "4". At that point, we can do something to actually display the data:

...
function getJobs(theUrl){

   document.getElementById("jobs").innerHTML = "Sending...";

   var request = GXmlHttp.create();
   request.open('GET', 'proxy.php?url='+URLencode(theUrl), true);
   request.onreadystatechange = function() {
      if (request.readyState == 4) {
         var jobDoc = GXml.parse(request.responseText);
	 displayJobs(jobDoc);
      }
   };
   request.send(null);

}

function displayJobs(jobDoc){

   var totalResultsElement = jobDoc.documentElement.getElementsByTagName("totalresults").item(0);
   var numberOfJobs = totalResultsElement.firstChild.nodeValue;

   var jobString = "There are "+numberOfJobs+" jobs.<br />";
   
   document.getElementById("jobs").innerHTML = jobString;

}

function URLencode(sStr) {
     return escape(sStr).replace(/\+/g, '%2B').replace(/\"/g,'%22').replace(/\'/g, '%27').replace(/\//g,'%2F');
}

</script>
...

The first step is to turn the retreived text into XML. Once again it's Google to the rescue, with the GXml object's static parse() method, which keeps us from trying to figure out how to access this particular browser's parser. In fact, if no parser is available, this method uses a Javascript parser to take up the slack.

The GXml.parse() function returns a DOM Document, which we can then pass to the displayJobs() function and analyze it just like any other Document. Here we're retrieving the value of the text in the totalresults element. (Java developers, remember the binding is slightly different for Javascript.) Once we have the results, we can display it in the jobs div. You can see the results here.

Actually, there is also an easier way to do this. The GXml object also includes the value() function, which provides the text value for an element:

...
function displayJobs(jobDoc){

   var totalResultsElement = jobDoc.documentElement.getElementsByTagName("totalresults").item(0);
   var numberOfJobs = GXml.value(totalResultsElement);

   var jobString = "There are "+numberOfJobs+" jobs.<br />";
   
   document.getElementById("jobs").innerHTML = jobString;

}
...

This function will come in very handy when we're ready to build the actual results:

...
function displayJobs(jobDoc){

   var totalResultsElement = jobDoc.documentElement.getElementsByTagName("totalresults").item(0);
   var numberOfJobs = GXml.value(totalResultsElement);

   var jobString = "There are "+numberOfJobs+" jobs.<br />";
   
   var jobsElement = jobDoc.documentElement.getElementsByTagName("results").item(0);
   var jobsList = jobsElement.getElementsByTagName("result");
   var numberOfJobsOnThisPage = jobsList.length;

   jobString = jobString + "<table>";

   for (i = 0; i < numberOfJobsOnThisPage; i++){

       var thisJob = jobsList.item(i);
       var infoUrl = GXml.value(thisJob.getElementsByTagName("url").item(0));
       var jobtitle = GXml.value(thisJob.getElementsByTagName("jobtitle").item(0));
       var company = GXml.value(thisJob.getElementsByTagName("company").item(0));
       var city = GXml.value(thisJob.getElementsByTagName("city").item(0));
       var state = GXml.value(thisJob.getElementsByTagName("state").item(0));
       var country = GXml.value(thisJob.getElementsByTagName("country").item(0));
       var snippet = GXml.value(thisJob.getElementsByTagName("snippet").item(0));
       
       jobString = jobString + "<tr><td><b><a href='"+infoUrl+"'>"+jobtitle+"</a>, "+company+"</b></td>";
       jobString = jobString + "<td>"+city+", "+state+", "+country+"</td></tr>";
       jobString = jobString + "<tr><td colspan='2'>"+snippet+"</td></tr>";

   }
   
   jobString = jobString + "<tr><td colspan ='2'>Results from <a href='http://www.indeed.com'>Indeed</a></td></tr>";
   jobString = jobString + "</table>";

   
   document.getElementById("jobs").innerHTML = jobString;

}

The first step is to get a NodeList of all of the result elements. Once we have that, we can loop through the list, retrieving the appropriate data for each value in using it to build a string of HTML text. In this case, we're formatting the data as an HTML table. Also, as required, we're linking back to Indeed at the bottom. Once we have a string, we set it as the HTML for the jobs div. You can see the results here.

Okay, that's our second API. Next, we'll add a third API and put them all together.

< Back Page 260 of 278 Next >

🔖 Save To Your Account

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.

Privacy Notice

Overview

Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information

To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.

Surveys

Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.

Newsletters

If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information

Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.

Security

Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.

Children

This site is not directed to children under the age of 13.

Marketing

Pearson may send or direct marketing communications to users, provided that

Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
Such marketing is consistent with applicable law and Pearson's legal obligations.
Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information

If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.

Choice/Opt-out

Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information

Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents

California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure

Pearson may disclose personal information, as follows:

As required by law.
With the consent of the individual (or their parent, if the individual is a minor)
In response to a subpoena, court order or legal process, to the extent permitted or required by law
To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
To investigate or address actual or suspected fraud or other illegal activities
To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.

Links

This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact

Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice

We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020

Email Address