Registration Options

There are a number of options you can set when making a new registration; for all of the options below you make a RegistrationOptions instance.


The match= registration option can be set to one of three values and affects how the dealer matching incoming “call” URIs.

  • exact: only a call to the exact URI will succeed

  • prefix: if the first part of the URI matches, the procedure will be invoked

  • wildcard: accepts any value for the portions of the URI accepting wildcards (denoted by two dots together, like com.example..postfix). So calling com.example.42.postfix would match with the wildcard matcher.


The invoke= registration option controls whether multiple components can register at the same URIs and how to behave when they are.

  • single: only one session may register at a time

  • first: multiple sessions may register, but only the first one is invoked

  • last: multiple sessions may register, and only the last one is invoked

  • roundrobin: multiple sessions may register each is invoked in order

  • random: multiple sessions may register and an arbitrary one is invoked


Controlling the number of concurrent, outstanding calls that can exist for a single endpoint. An “outstanding call” is when we’ve invoked a procedure, but its coroutine/Future/Deferred hasn’t completed yet. If concurrency=0 (the default) than any number of calls can exist at once. Otherwise, once the concurrency limit is reached any subsequent callers will get an error message.


When set to True this allows subsequent sessions to “kick out” any current registrations; those previous registration must have also specified force_reregister=True.


If you want the invoked procedure to receive a CallDetails instance, specify which argument-name to send it in with details_arg. For example, details_arg="details" will cause all calls to the registered procedure to receive a details=CallDatails() kwarg.

correlation_id, correlation_uri, correlation_is_anchor, correlation_is_last

These options all relate to the “tracing” feature.