ZMQ::Socket::Router

Constants

TYPE_STR

ZMQ::Socket::Router

A socket of type ZMQ::Socket::Router is an advanced pattern used for extending request/reply sockets. When receiving messages a ZMQ::Socket::Router socket shall prepend a message part containing the identity of the originating peer to the message before passing it to the application. Messages received are fair-queued from among all connected peers. When sending messages a ZMQ::Socket::Router socket shall remove the first part of the message and use it to determine the identity of the peer the message shall be routed to. If the peer does not exist anymore the message shall be silently discarded.

Previously this socket was called ZMQ_XREP and that name remains available for backwards compatibility.

When a ZMQ::Socket::Router socket enters an exceptional state due to having reached the high water mark for all peers, or if there are no peers at all, then any messages sent to the socket shall be dropped until the exceptional state ends. Likewise, any messages routed to a non-existent peer or a peer for which the individual high water mark has been reached shall also be dropped.

When a ZMQ::Socket::Request socket is connected to a ZMQ::Socket::Router socket, in addition to the identity of the originating peer each message received shall contain an empty delimiter message part. Hence, the entire structure of each received message as seen by the application becomes: one or more identity parts, delimiter part, one or more body parts. When sending replies to a ZMQ::Socket::Request socket the application must include the delimiter part.

Summary of ZMQ_ROUTER characteristics

Compatible peer socket

ZMQ::Socket::Dealer, ZMQ::Socket::Req, ZMQ::Socket::Rep

Direction

Bidirectional

Send/receive pattern

Unrestricted

Outgoing routing strategy

See text

Incoming routing strategy

Fair-queued

ZMQ::Socket#hwm option action

Drop