Updated exchange-attributes.txt

AlexanderSemenets authored
revision 5c5136413e3e0d951bcc6b222600bae1e312b345
exchange-attributes
# Exchange attributes

### - Name
### - Type
### - Durability
Exchanges can be durable or transient. Durable exchanges survive broker restart, transient exchanges do not (they have to be redeclared when the broker comes back online).
### - Auto delete
If yes, the exchange will delete itself after at least one queue or exchange has been bound to this one, and then all queues or exchanges have been unbound.
### - Internal
If yes, clients cannot publish to this exchange directly. It can only be used with exchange to exchange bindings.
### - Alternate-exchange
If messages to this exchange cannot otherwise be routed, send them to the alternate exchange named here.

It is sometimes desirable to let clients handle messages that an exchange was unable to route (i.e. either because there were no bound queues our no matching bindings). Typical examples of this are

detecting when clients accidentally or maliciously publish messages that cannot be routed
"or else" routing semantics where some messages are handled specially and the rest by a generic handler