archive: Read/write Objects <> Archive Files with Data Verification

View source: R/archive.R

archiveR Documentation

Read/write Objects <> Archive Files with Data Verification

Description

Read and write objects to/from archival storage in the native RData format, with verification of data integrity.

Usage

archive(..., object, file)

Arguments

...

unnamed arguments will be parsed as 'file' if there is only one argument, 'object' and 'file' if there are two arguments.

object

(for write operations) an object.

file

the name of the file or a connection where the object is saved to or read from.

Details

For read operations: specify only 'file', or alternatively if no arguments are specified, a system dialog will be opened allowing a file to be chosen interactively. 'file' is read and the return value may be assigned to an object. A confirmation message is issued if the file read operation has been successful.

For write operations: specify both 'object' and 'file'. If only 'object' is specified and 'file' is left empty (see examples), a system dialog will be opened allowing the file save location to be chosen interactively. 'object' will be written to 'file'. A confirmation message is issued if the file write operation has been successful.

Value

For read operations: the object originally archived.

For write operations: invisible NULL. 'object' is written to 'file'.

Data Verification

If the 'openssl' package is available, a sha256 hash of the original object is written to the archive. This allows the data integrity of the restored object to be verified when the archive is read back.

For write operations: confirmation of the sha256 hash is displayed if this has been successfully written to file.

For read operations: a 'data verified' message is issued if the sha256 hash found within the data file has been authenticated.

Further Details

Please refer to the reference vignette by calling: vignette("reference", package = "ichimoku")

Examples

cloud <- ichimoku(sample_ohlc_data, ticker = "TKR")
file <- tempfile()

archive(cloud, file)

restored <- archive(file)

unlink(file)

if (interactive()) {
# Only run examples in interactive R sessions
# Read file to 'object' using system dialog:
object <- archive()

# Write 'cloud' to file using system dialog:
archive(cloud, )
}


ichimoku documentation built on May 23, 2022, 9:05 a.m.