Creates a new Dialer and binds it to a Socket.
Arguments
- socket
a Socket.
- url
[default 'inproc://nanonext'] a URL to dial, specifying the transport and address as a character string e.g. 'inproc://anyvalue' or 'tcp://127.0.0.1:5555' (see transports).
- tls
[default NULL] for secure tls+tcp:// or wss:// connections only, provide a TLS configuration object created by
tls_config.- autostart
[default TRUE] whether to start the dialer (by default asynchronously). Set to NA to start synchronously - this is less resilient if a connection is not immediately possible, but avoids subtle errors from attempting to use the socket before an asynchronous dial has completed. Set to FALSE if setting configuration options on the dialer as it is not generally possible to change these once started.
- error
[default FALSE] behaviour on error: if FALSE, returns an integer exit code accompanied by a warning, or, if TRUE, generates an error and halts execution.
Value
Invisibly, an integer exit code (zero on success). A new Dialer (object of class ‘nanoDialer’ and ‘nano’) is created and bound to the Socket if successful.
Details
To view all Dialers bound to a socket use $dialer on the socket, which
returns a list of Dialer objects. To access any individual Dialer (e.g. to
set options on it), index into the list e.g. $dialer[[1]] to return
the first Dialer.
A Dialer is an external pointer to a dialer object, which creates a single outgoing connection at a time. If the connection is broken, or fails, the dialer object will automatically attempt to reconnect, and will keep doing so until the dialer or socket is destroyed.
Further details
Dialers and Listeners are always associated with a single socket. A given socket may have multiple Listeners and/or multiple Dialers.
The client/server relationship described by dialer/listener is completely orthogonal to any similar relationship in the protocols. For example, a rep socket may use a dialer to connect to a listener on an req socket. This orthogonality can lead to innovative solutions to otherwise challenging communications problems.
Any configuration options on the dialer/listener should be set by
opt<- before starting the dialer/listener with
start.
Dialers/Listeners may be destroyed by close. They are also
closed when their associated socket is closed.
Examples
socket <- socket("rep")
dial(socket, url = "tcp://127.0.0.1:6545", autostart = FALSE)
socket$dialer
#> [[1]]
#> < nanoDialer >
#> - id: 3
#> - socket: 7
#> - state: not started
#> - url: tcp://127.0.0.1:6545
#>
start(socket$dialer[[1]])
socket$dialer
#> [[1]]
#> < nanoDialer >
#> - id: 3
#> - socket: 7
#> - state: started
#> - url: tcp://127.0.0.1:6545
#>
close(socket$dialer[[1]])
close(socket)
nano <- nano("bus")
nano$dial(url = "tcp://127.0.0.1:6546", autostart = FALSE)
nano$dialer
#> [[1]]
#> < nanoDialer >
#> - id: 4
#> - socket: 8
#> - state: not started
#> - url: tcp://127.0.0.1:6546
#>
nano$dialer_start()
nano$dialer
#> [[1]]
#> < nanoDialer >
#> - id: 4
#> - socket: 8
#> - state: started
#> - url: tcp://127.0.0.1:6546
#>
close(nano$dialer[[1]])
nano$close()