pointblank (version 0.7.0)

affix_date: Put the current date into a file name

Description

This function helps to affix the current date to a filename. This is useful when writing agent and/or informant objects to disk as part of a continuous process. The date can be in terms of UTC time or the local system time. The date can be affixed either to the end of the filename (before the file extension) or at the beginning with a customizable delimiter.

The x_write_disk(), yaml_write() functions allow for the writing of pointblank objects to disk. Furthermore the log4r_step() function has the append_to argument that accepts filenames, and, it's reasonable that a series of log files could be differentiated by a date component in the naming scheme. The modification of the filename string takes effect immediately but not at the time of writing a file to disk. In most cases, especially when using affix_date() with the aforementioned file-writing functions, the file timestamps should approximate the time components affixed to the filenames.

Usage

affix_date(
  filename,
  position = c("end", "start"),
  format = "%Y-%m-%d",
  delimiter = "_",
  utc_time = TRUE
)

Arguments

filename

The filename to modify.

position

Where to place the formatted date. This could either be at the "end" of the filename (the default) or at the "start".

format

A base::strptime() format string for formatting the date. By default, this is "%Y-%m-%d" which expresses the date according to the ISO 8601 standard (as YYYY-MM-DD). Refer to the documentation on base::strptime() for conversion specifications if planning to use a different format string.

delimiter

The delimiter characters to use for separating the date string from the original file name.

utc_time

An option for whether to use the current UTC time to establish the date (the default, with TRUE), or, use the system's local time (FALSE).

Value

A character vector.

Function ID

12-3

See Also

The affix_datetime() function provides the same features except it produces a date-time string by default.

Other Utility and Helper Functions: affix_datetime(), col_schema(), from_github(), has_columns(), stop_if_not()

Examples

# NOT RUN {
# Taking the generic `pb_file` name for
# a file, we add the current date to it
# as a suffix
affix_date(filename = "pb_file")

# File extensions won't get in the way:
affix_date(filename = "pb_file.rds")

# The date can be used as a prefix
affix_date(
  filename = "pb_file",
  position = "start"
)

# The date pattern can be changed and so
# can the delimiter
affix_date(
  filename = "pb_file.yml",
  format = "%Y%m%d",
  delimiter = "-"
)

if (interactive()) {

# We can use a file-naming convention
# involving dates when writing output
# files immediately after interrogating;
# useful when interrogating directly
# from YAML in a scheduled process
yaml_agent_interrogate(
  filename = system.file(
    "yaml", "agent-small_table.yml",
    package = "pointblank"
  )
) %>% 
  x_write_disk(
    filename = affix_date(
      filename = "small_table_agent.rds",
      delimiter = "-"
    ),
    keep_tbl = TRUE,
    keep_extracts = TRUE
  )

}

# }