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'Running your first Web Services in 15 minutes' for Windows 95, 98, NT & 2000

A tutorial reproduced by permission of Salcentral

How To Guide? So what is the Search Engine for?
It is all very well us telling everyone that this is the worlds first WSDL search engine (in the left nav bar of this page), but because this part of the industry is still very much in its infancy, we're constantly getting emails asking 'What is a WSDL' or 'how do I use them'. Well here's our best go at producing a *very* brief description of how to use a WSDL schema from the library.

This document is meant to be a quick and simple guide to running your first web service, so follow the step by step guide and you should be up and running your first web service in 15 minutes (fingers crossed)!

A Brief Explanation of Web Services
Firstly a WSDL schema is simply a text file which describes a process which you can use/run on a remote server on the internet. It describes...

The functions or methods it has available
The arguments each function requires
The location of the server that can run that functionality

However its not much use on its own, so you also need a piece of software on your computer that understands this schema and can create methods, set arguments and talk to the server on your behalf.

This is where a SOAP toolkit can help...

There are a number of excellent toolkits available at the moment, for the sake of this simple tutorial we have chosen the SOAP:Net implementation.

Tutorial for 'Running your first Web Services in 15 minutes' for Windows 95, 98, NT & 2000

Download and install SOAP:Net from...

Soap:Net for Windows 95, 98, NT & 2000

Now lets find a web service we'd like to run. The below search is an exact duplication of how the main search screen works. The WSDL schema we are going to use to run our web service, defines a service that translates text from English into French...

Below is a snippet of the search screen showing what you should see after performing the search...

The Schema location shown above and located at https://www.xmethods.net/sd/BabelFishService.wsdl is the important bit, this is the WSDL schema that actually defines what functions & arguments you are allowed to run along with also identifying the server location that runs those functions.

Load the following page, this has a bit of vbScript which runs all the necessary objects locally on your machine (after you have installed SOAP:Net) and executes the web service on the remote SOAP server.

My First Web Service

Press the 'Translate NOW' button on the My First Web Service page....

If you received back a valid translation, then that's it, you've just run your first remote web service.
If the code did not run please see Troubleshooting Notes below...

However, it didn't really explain a lot about what's happening... So lets briefly look at some of the code we've used...
(The following code can be copied into either a Microsoft Visual Basic® project or into a web page as vbScript using the appropriate script tags)

Dim oBA	'Use the business area component to create functions and hold schemas
Dim oEX	'Execute component that talks to the remote server

Set oBA = CreateObject("lcTkPoSBA.CSOAPBusinessArea")	'Create business area
Set oEX = CreateObject("lcTkPoEXE.CSOAPExecute")	'Create execute function

oEx.GetSchemas oBA, "https://www.xmethods.net/sd/BabelFishService.wsdl"	'Add schema into the business area (you can add multiple schemas if required)

oBA.SP.Add "BabelFishService","BabelFish"	'Create a function or method off the business area, ready to send to the remote SOAP server (you can add multiple functions if the server supports it).

oBA.SP("BabelFish")("translationmode")="en_fr"	'Set the ' translationmode' argument (this argument is specific to the BabelFishService web service, other web services will have differently named arguments, or may have no arguments). In the 'My First Web Service' page this value is taken from the forms field.
oBA.SP("BabelFish")("sourcedata")="Hello sir"	'Set the 'sourcedata' argument. In the 'My First Web Service' page this value is taken from the forms field.

oEX.Execute oBA	'Now execute the process against the remote server.

msgbox oBA.SP("Babelfish")("return")	'Now display the return value from the web service. In the 'My First Web Service' page this value is put into one of the forms fields.

Troubleshooting Notes

'ActiveX component can't create object' error then you need to change the "Initialize and script ActiveX controls not marked as safe" option on the security tab inside Internet Explorer from Disable to Prompt. If the problem persists ensure that you have downloaded and installed SOAP:Net from Soap:Net for Windows 95, 98, NT & 2000. Please note any previous copies of SOAP:Net (previously the Lucin SOAP Toolkit) must be uninstalled before a new version is installed. If the problem continues to persist, and you have not rebooted your machine since the installation of SOAP:Net, reboot your machine.

'Error on page' or 'Error' appears at the bottom of the page Ensure that the security internet settings allow your browser to 'Run ActiveX controls and plug-ins' (change this option from 'disable' to 'prompt' or 'enable') and 'Initialize and script ActiveX controls not marked as safe' (again, change this to 'prompt' or 'enable').

'Server failed to return any data' Try again, this is likely to only be a very temporary problem, if the problem persists, contact [email protected] for an alternative server.

Any other problems email us at [email protected].

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