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The following page has been changed by PaulFremantle: http://wiki.apache.org/ws/Synapse/200509F2F ------------------------------------------------------------------------------ * Configure a new endpoint * Configure a raw pass-thru mediation between a listener and endpoint + === Core Model === - ====XML============== + There is a rule: match -> mediation component approach + + Suppose I want to log every message, and then run tranform mediation on the stockquote service. + + rules + * -> LogMediation, QoS markers + http://xmethods.net/stockquote -> StockXFormMediation, QoS markers + + This could be used as a "composition" model, but that is not the primary aim. Primarily compositions happen statically + inside a mediation. So for example, we may provide a BPELMediation that use BPEL syntax to compose sub-mediations. Alternatively, we may provide some logical composition components (chain, branch, tee) that can be combined to compose mediations. + + However, there is some differences between using the rule model and the mediation composition mode: + + 1. The invocation of a Mediation component by the framework is a single thread - so multiple rule matches may operate on separate threads (e.g. above, the logging may happen on a different thread to the xform). + + 2. The QoS markers are only at the level of a rule. So mediation writers can do what they like inside a mediation. So if a mediation wants to launch a new AxisEngine to get the security handlers invoked it can. + + 3. The rule matching is inherently dynamic, whereas the mediations are more statically defined and deployed. (of course a mediation is just Java so it can do as much dynamic stuff as any other Java - reflection, classloading, etc). + + Rules can be added dynamically. + + In fact because the system is inherently one-way, sometimes we will automatically add a new tule that matches an async response. + + === XML === + We could write our own serialisation + <sxl> <match xpath="wsa:To/address=http://dims.com/tricky"/> <mediation name="dims"> <param name="finalendpoint" value="http://paul.com/easy"/> </mediation> </sxl> + + + or use Policy attachment <wsp:PolicyAttachment> <AppliesTo> @@ -85, +114 @@ </Policy> </wsp:PolicyAttachment> + Another option would be to have an ASCII/LEX serialisation that transforms to/from the PolAttachment model above. +
