iWay Functional Language

iWay Service Manager (iSM) provides the iWay Functional Language (iFL), which can be used to configure parameters in iSM components. iFL can obtain information to be used for this configuration from:

• External sources (for example, property files or the system environment).
• The message context and characteristics (for example, MSMQ, HTTP headers, or message length).
• The message itself (for example, XPath or JsonPath, JsonPointer).

iFL also offers string processing, conditional expressions, and scoped variables.

For example, an application receives an XML document containing an address to send as a response. If the host cannot be reached, then a default alternate is stored in a property file. The Alternate Route IP Service (com.ibi.agents.XDAltRouteIP) checks to determine whether the primary host can be reached. If the primary host cannot be reached, then an alternate host is selected by this service. The alternate host name to be used is stored in a subsequent emit operation in a variable (called a Special Register or SREG). The subsequent emit service can access the selected host name using the following iFL _sreg() function:

_sreg('activehost')

If the incoming message was a JSON document, then the value for the Host parameter that is shown in this example might be:

_jsonptr('/root/sendto')

For more detailed information about using iFL and all of the functions that are available, see the iWay Functional Language Reference Guide.