Create Serialization Configuration — serial

Returns a serialization configuration, which may be set to perform custom serialization and unserialization of normally non-exportable reference objects, allowing these to be used seamlessly between different R sessions. Once set by passing to the serial argument of daemons(), the functions apply to all mirai requests for that compute profile.

Usage

serial_config(class, sfunc, ufunc)

Arguments

class: (character) class name(s) for custom serialization, e.g. 'ArrowTabular' or c('torch_tensor', 'ArrowTabular').
sfunc: (function | list) serialization function(s) accepting a reference object and returning a raw vector.
ufunc: (function | list) unserialization function(s) accepting a raw vector and returning a reference object.

Value

A list comprising the configuration. This should be passed to the serial argument of daemons().

Details

This feature utilises the 'refhook' system of R native serialization.

An error in sfunc (serialization) is raised directly in the calling process, e.g. the mirai() call itself errors and the task is not dispatched.

An error in ufunc (unserialization) is caught, and the object instead unserializes as an 'errorValue' 1000 ('Internal error detected'). This prevents a faulty hook from crashing the daemon.

Examples

cfg <- serial_config("test_cls", function(x) serialize(x, NULL), unserialize)
cfg
#> [[1]]
#> [1] "test_cls"
#> 
#> [[2]]
#> [[2]][[1]]
#> function (x) 
#> serialize(x, NULL)
#> <environment: 0x55cc5dd58960>
#> 
#> 
#> [[3]]
#> [[3]][[1]]
#> function (connection, refhook = NULL) 
#> {
#>     if (typeof(connection) != "raw" && !is.character(connection) && 
#>         !inherits(connection, "connection")) 
#>         stop("'connection' must be a connection")
#>     .Internal(unserialize(connection, refhook))
#> }
#> <bytecode: 0x55cc5dd3c880>
#> <environment: namespace:base>
#> 
#> 

cfg2 <- serial_config(
  c("class_one", "class_two"),
  list(function(x) serialize(x, NULL), function(x) serialize(x, NULL)),
  list(unserialize, unserialize)
)
cfg2
#> [[1]]
#> [1] "class_one" "class_two"
#> 
#> [[2]]
#> [[2]][[1]]
#> function (x) 
#> serialize(x, NULL)
#> <environment: 0x55cc5dd58960>
#> 
#> [[2]][[2]]
#> function (x) 
#> serialize(x, NULL)
#> <environment: 0x55cc5dd58960>
#> 
#> 
#> [[3]]
#> [[3]][[1]]
#> function (connection, refhook = NULL) 
#> {
#>     if (typeof(connection) != "raw" && !is.character(connection) && 
#>         !inherits(connection, "connection")) 
#>         stop("'connection' must be a connection")
#>     .Internal(unserialize(connection, refhook))
#> }
#> <bytecode: 0x55cc5dd3c880>
#> <environment: namespace:base>
#> 
#> [[3]][[2]]
#> function (connection, refhook = NULL) 
#> {
#>     if (typeof(connection) != "raw" && !is.character(connection) && 
#>         !inherits(connection, "connection")) 
#>         stop("'connection' must be a connection")
#>     .Internal(unserialize(connection, refhook))
#> }
#> <bytecode: 0x55cc5dd3c880>
#> <environment: namespace:base>
#> 
#>