Oracle APEX Tutorial – A Web Service – Part 1

Oracle APEX Tutorial – A Web Service – Part 1

Introduction


As the world moves forward, there is a higher need for more information. However, it is a near impossible task to create and manage all this information yourself. Sometimes, it’s easier to use freely availible services and information feeds provided by others. One such ‘feed’ is a Web Service. By sending a properly formed request to another group over the web, you can receive information back, and display it on your screen. A popular and easy to visualize example of this is getting the local Movie Theater times and titles for current movies. This tutorial will show how to do this.

Part 1 – Creating the Base Application and Services

High Level Steps

1) Create Base Application (0:30)
2) Specify Proxy Settings (optional) (2:18)
3) Create a Web Service by WDSL (2:53)
4) Dreate a Web Service Manually (6:00)

The times in parenthesis are approximate start times for that step

Notes and Resources

Web Services

Web Services are somewhat like the web itself, and can be transient in nature. Due to this, the information presented in this tutorial is accurate as of the time the tutorial was made. However, there may be changes in the Web Service link, procedures, returned data and other factors since the creation of this document. Web Services can by found by either manually entering the information needed (as we are doing in this tutorial) or by use of the UDDI (Universal Description, Discovery and Integration) registry, which is a directory where businesses have submitted thier available Web Services information for others to browse and use.

SOAP

SOAP is the abbreviation for Simple Object Access Protocol. It is an attempt to provide a platform neutral way to exchange requests and results across the Internet. The SOAP standards are maintained by the W3C, and may be superceeded in future protocol standards.

Testing Manual Services

Whenever you create and test a manual service it accomplishes two things. One it tells you if you are getting back the correct information, and two, it allows you to find the information refrences you may need later when building the displayed report. In our case, embedded in the returned results for the Movie Info service there are a few things we need to take note of. One is the ‘base node’, another is the ‘namespace’, also there is the ‘XPath’ and the ‘interesting elements’ All of these will be used in the creation of the end report, so it’s important to know them. Of course, this means that you should have a good idea of the data you need from the web service before you go invoking it.

Code and Pasted Text

WSDL Location Field

http://www.ignyte.com/webservices/ignyte.whatsshowing.webs
ervice/moviefunctions.asmx?wsdl

Manual Service Creation URL and Action

http://www.ignyte.com/webservices/ignyte.whatsshowing.webs
ervice/moviefunctions.asmx

http://www.ignyte.com/whatsshowing/GetTheatersAndMovies

Manual Creation SOAP Envelope

<?xml version="1.0" encoding="UTF-8"?>
<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"
xmlns:tns="http://www.ignyte.com/whatsshowing"
xmlns:xs="http://www.w3.org/2001/XMLSchema">
<soap:Body>
<tns:GetTheatersAndMovies>
<tns:zipCode>#ZIP#</tns:zipCode>
<tns:radius>#RADIUS#</tns:radius>
</tns:GetTheatersAndMovies>
</soap:Body>
</soap:Envelope>

SOAP Response

MOVIE_RESULTS