Web Services for Info Explorer Zones
- by Anthony Shorten
One of the most interesting uses for XAI and Configurable objects is the exposure of a query portal as a Web Service. Let me illustrate this with an example. Say you have an interface that requires a list of data from a number of product tables. In the past you would have to build a java program to do this with SQL then use an application service but it is now possible with just configuration.
The first step in the process is to create the SQL you want to use for the interface. It can be any valid static SQL or use host variables for the WHERE clause (we call that filtered). Once you are happy with the SQL (and it performs acceptably) you can incorporate that SQL into a Info-Explorer Zone. You can use any of the explorer zone types but I typically recommend F1-DE-SINGLE as it supports a single SQL statement with multiple filters (up to 15) as well as hidden filters (up to 5). Hidden filters are typically not displayed in the UI for criteria (remember explorer zones can be used on the user Interface as well) but for web services they can be used as normal filters (this means you can use up to 20 filters all up).
Once you are happy with the zone, you now need to define it as a Business Service. We have a generic service called FWLZDEXP which allows a explorer zone to be defined as a Business Service. If you open any Business Service based upon FWLZDEXP you will see some examples. The schema is standard and pretty self explanatory in terms of the structure. The schema pattern looks like this:
Zone element - maps to the ZONE_CD element and the default value is the zone name you just created. This links the business service to the zone.
Filter elements - You name the filters as you like but the mapField is set to Fx_VALUE where x is the filter number corresponding to the filter element in the zone definition.
Hidden filter elements - You name the filters as you like but the mapField is set to Hx_VALUE where x is the filter number corresponding to the hidden filter element in the zone definition.
results group - this holds the elements of the result set. Each element in your result set has a tagname and is linked to the COL_VALUE mapField and the row element is lists the SEQNO of the column. This corresponds to the column number in the results set in the zone.
An example schema is shown below for the F1-USGRACML zone, which returns the access modes for a user group and application service filters.
In the example, the userGroup and applicationService elements are the filters and the rows would contain a list of accessModeDescr. This is just a simple example to illustrate the point. There are lots of examples in the product that you can investigate.
One recommendation, to save time, is that you copy the schema from one of the examples to save you typing it from scratch. You can simply modify the tags and other elements to suit your needs.
Once the Business Service is defined it can simply be defined as a Web Service by registering an XAI Inbound Service using the Business Service definition as a basis.
You now have a Web Service based upon a Info Explorer Zone.
This is one of my favorite components as it allows interfaces to be simplified.
This will be my last blog entry for this year. I hope you all have a great and safe Christmas and an even greater new year. Next year promises to be an exciting year and I look forward to communicating exciting developments we are working on at the moment as they are released.
