Static and dynamic connectivity chains
Chains can be created statically using a YAML configuration file or dynamically at runtime. How the chains are created depends on the type of transport:
Some transports have a dynamic chain manager which manages chain creation in a transport-specific way. New chains are created, for example:
in response to external requests (for example, for each connection made to the HTTP server connectivity plug-in), or
when an Apama channel with a particular prefix is first used from EPL (for example, the
Universal Messaging connectivity plug-in creates a chain by default when a channel beginning with
um: is used from EPL, in a
monitor.subscribe(...) method or a
send ... to statement).
These transports always have a
dynamicChainManagers section in their YAML configuration file. The connectivity chains are created dynamically by a transport chain manager plug-in, using chain definitions specified in
dynamicChains. See
Configuration file for connectivity plug-ins for information on how to configure dynamic chain managers and dynamic chains in a YAML configuration file.
For transports that do not provide a dynamic chain manager, chains are created either
statically using the
startChains section of the YAML file, or
A transport that permits user-controlled chain creation never has a dynamicChainManagers section in its YAML configuration file.
See the documentation for each transport in
Standard Connectivity Plug-ins on how chains are created. See
Configuration file for connectivity plug-ins for more details on
startChains,
dynamicChains and
dynamicChainManagers.