Create a nano object, encapsulating a Socket, Dialers/Listeners and associated methods.

nano(
  protocol = c("bus", "pair", "push", "pull", "pub", "sub", "req", "rep", "surveyor",
    "respondent"),
  dial = NULL,
  listen = NULL,
  tls = NULL,
  autostart = TRUE
)

Arguments

protocol

[default 'bus'] choose protocol - 'bus', 'pair', 'push', 'pull', 'pub', 'sub', 'req', 'rep', 'surveyor', or 'respondent' - see protocols.

dial

(optional) 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).

listen

(optional) a URL to listen at, 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/listener. Set to FALSE if setting configuration options on the dialer/listener as it is not generally possible to change these once started. For dialers only: 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.

Value

A nano object of class 'nanoObject'.

Details

This function encapsulates a Socket, Dialer and/or Listener, and its associated methods.

The Socket may be accessed by $socket, and the Dialer or Listener by $dialer[[1]] or $listener[[1]] respectively.

The object's methods may be accessed by $ e.g. $send() or $recv(). These methods mirror their functional equivalents, with the same arguments and defaults, apart from that the first argument of the functional equivalent is mapped to the object's encapsulated socket (or context, if active) and does not need to be supplied.

More complex network topologies may be created by binding further dialers or listeners using the object's $dial() and $listen() methods. The new dialer/listener will be attached to the object e.g. if the object already has a dialer, then at $dialer[[2]] etc.

Note that $dialer_opt() and $listener_opt() methods will be available once dialers/listeners are attached to the object. These methods get or apply settings for all dialers or listeners equally. To get or apply settings for individual dialers/listeners, access them directly via $dialer[[2]] or $listener[[2]] etc.

The methods $opt(), and also $dialer_opt() or $listener_opt() as may be applicable, will get the requested option if a single argument 'name' is provided, and will set the value for the option if both arguments 'name' and 'value' are provided.

For Dialers or Listeners not automatically started, the $dialer_start() or $listener_start() methods will be available. These act on the most recently created Dialer or Listener respectively.

For applicable protocols, new contexts may be created by using the $context_open() method. This will attach a new context at $context as well as a $context_close() method. While a context is active, all object methods use the context rather than the socket. A new context may be created by calling $context_open(), which will replace any existing context. It is only necessary to use $context_close() to close the existing context and revert to using the socket.

Examples

nano <- nano("bus", listen = "inproc://nanonext")
nano
#> < nano object >
#>  - socket id: 18
#>  - state: opened
#>  - protocol: bus
#>  - listener:
#>     inproc://nanonext
nano$socket
#> < nanoSocket >
#>  - id: 18
#>  - state: opened
#>  - protocol: bus
#>  - listener:
#>     inproc://nanonext
nano$listener[[1]]
#> < nanoListener >
#>  - id: 9
#>  - socket: 18
#>  - state: started
#>  - url: inproc://nanonext

nano$opt("send-timeout", 1500)
nano$opt("send-timeout")
#> [1] 1500

nano$listen(url = "inproc://nanonextgen")
nano$listener
#> [[1]]
#> < nanoListener >
#>  - id: 9
#>  - socket: 18
#>  - state: started
#>  - url: inproc://nanonext
#> 
#> [[2]]
#> < nanoListener >
#>  - id: 10
#>  - socket: 18
#>  - state: started
#>  - url: inproc://nanonextgen
#> 

nano1 <- nano("bus", dial = "inproc://nanonext")
nano$send("example test", mode = "raw")
#> [1] 0
nano1$recv("character")
#> [1] "example test"

nano$close()
nano1$close()