route keyword

(Back to Integration Flow Language Specification)

Child Keywords

• from
  • pipe and filter pattern
• to
  • pipe and filter pattern
• broadcast
  • scatter-gather pattern
• split
  • splitter pattern
• aggregate
  • aggregator pattern / scatter-gather pattern
• select
  • content-based router
• filter
  • message filter pattern
• tee
  • wire tap pattern

Basic syntax

Is to declare a route code block as an IFL roote element (not nested in another route):

route do
  from "<logical service name 1>"  # occurs once 
  to "<logical service name 2>"    # occurs 0 or more times
end

Alternate simplified syntax

When only one "from" and "to" is used:

route from "<logical service name 1>" to "<logical service name 2>"

route With Composite Constructs

Instead of the simple "to" of the pipe-and-filter pattern, the other EIP keywords can be inserted. For example adding a broadcast to the route:

route do
  from "<logical service name 1>"  # occurs at most once
  to "<logical service naem 2>"    # occurs 0 or more times
  broadcast do                            # occurs at most once within an enclosing route
     route to "<logical service name 3>"  # occurs 0 or more times
     route to "<logical service name 4>"  # occurs 0 or more times
  end
end

Note that for route used nested inside a broadcast (and in turn top level route) there is an implicit "from" as the message is piped from the preceding keyword and no "from" declaration is used:

Nexted route:

...
   route do
      to "<logical service name 2>"    # occurs 0 or more times
   end
...

Named route

Routes can be named so they can be called and included in other routes. It can be thought of as defining a re-usable endpoint, breaking the routing up into re-usable pieces. Named routes do not have a "from", implicitly messages come from routing messages to that route name/endpoint.

route "<my-route-name>" do
  to "<logical filter name 1>"   # occurs 0 or more times
  to "<logical service name>"  # occurs once
end

The named route "endpoint" can be referenced in the other IFL construct like any other service, i.e. to call the above one or more other routes could state (assuming a name of my-route-name):

route do
  from "my-trasnport"
  to "some-transform"  
  to "my-route-name"   
end

Scenarios:

One "from", one "to"

Defines the concrete routing of a message fom a calling service (sometimes termed an endpoint reference, a logical name the consumer of a service uses) to the implementing / provisioning service.

Example: an RSS service routes any new entries to an instant messaging server

route do
   from "cnnnewsfeed"
   to "IM"
end

One "from", two or more "to"

This declares the classic pipe and filter pattern; output from the preceding service (whether "from" or previous "to") it piped to the input of the next "to"

Example: an RSS service routes any new entries to filter implemented in JRuby, the output of the filter is routed to an instant messaging server

route do
   from "cnnnewsfeed"
   to "jrubyfilter"
   to "IM"
end

One "from", one or more composite constructs such as "broadcast":

Defines the concrete routing of a message fom a calling service (sometimes termed an endpoint reference, a logical name the consumer of a service uses) to the enterprise integration pattern implemented by the composite construct (e.g. "broadcast"), which then routes to the implementing / provisioning service(s).

Example: an RSS service routes any new entries to a broadcast enterpise integration pattern (composite construct), which sends a copy each in parallel to multiple services; in this case both to an instant messaging server and a file archive

route do
   from "cnnnewsfeed"
   broadcast do
       route to "IM"
       route to "filearchive"
   end
end

This page (revision-13) was last changed on 10-Dec-09 10:19 AM, -0800 by AndiEgloff.
This page was created on 04-May-08 17:00 PM, -0700 by AndiEgloff.

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