tar_config_unset: Unset configuration settings.
In targets: Dynamic Function-Oriented 'Make'-Like Declarative Pipelines

tar_config_unset

R Documentation

Unset configuration settings.

Description

Unset (i.e. delete) one or more custom settings for the current project from the optional YAML configuration file. After that, tar_option_get() will return the original default values for those settings for the project.

Usage

tar_config_unset(
  names = character(0),
  config = Sys.getenv("TAR_CONFIG", "_targets.yaml"),
  project = Sys.getenv("TAR_PROJECT", "main")
)

Arguments

`names`	Character vector of configuration settings to delete from the current project.
`config`	Character of length 1, file path of the YAML configuration file with `targets` project settings. The `config` argument specifies which YAML configuration file that `tar_config_get()` reads from or `tar_config_set()` writes to in a single function call. It does not globally change which configuration file is used in subsequent function calls. The default file path of the YAML file is always `⁠_targets.yaml⁠` unless you set another default path using the `TAR_CONFIG` environment variable, e.g. `Sys.setenv(TAR_CONFIG = "custom.yaml")`. This also has the effect of temporarily modifying the default arguments to other functions such as `tar_make()` because the default arguments to those functions are controlled by `tar_config_get()`.
`project`	Character of length 1, name of the current `targets` project. Thanks to the `config` R package, `targets` YAML configuration files can store multiple sets of configuration settings, with each set corresponding to its own project. The `project` argument allows you to set or get a configuration setting for a specific project for a given call to `tar_config_set()` or `tar_config_get()`. The default project is always called `"main"` unless you set another default project using the `TAR_PROJECT` environment variable, e.g. `Sys.setenv(tar_project = "custom")`. This also has the effect of temporarily modifying the default arguments to other functions such as `tar_make()` because the default arguments to those functions are controlled by `tar_config_get()`.

Value

NULL (invisibly)

Storage access

Several functions like tar_make(), tar_read(), tar_load(), tar_meta(), and tar_progress() read or modify the local data store of the pipeline. The local data store is in flux while a pipeline is running, and depending on how distributed computing or cloud computing is set up, not all targets can even reach it. So please do not call these functions from inside a target as part of a running pipeline. The only exception is literate programming target factories in the tarchetypes package such as tar_render() and tar_quarto().

Configuration

For several key functions like tar_make(), the default values of arguments are controlled though tar_config_get(). tar_config_get() retrieves data from an optional YAML configuration file. You can control the settings in the YAML file programmatically with tar_config_set(). The default file path of this YAML file is ⁠_targets.yaml⁠, and you can set another path globally using the TAR_CONFIG environment variable. The YAML file can store configuration settings for multiple projects, and you can globally set the default project with the TAR_PROJECT environment variable. The structure of the YAML file follows rules similar to the config R package, e.g. projects can inherit settings from one another using the inherits field. Exceptions include:

There is no requirement to have a configuration named "default".
Other projects do not inherit from the default project' automatically.
Not all fields need values because targets already has defaults.

targets does not actually invoke the config package. The implementation in targets was written from scratch without viewing or copying any part of the source code of config.

Examples

if (identical(Sys.getenv("TAR_EXAMPLES"), "true")) { # for CRAN
tar_dir({ # tar_dir() runs code from a temp dir for CRAN.
tar_script(list(tar_target(x, 1 + 1)))
tar_config_get("store") # "_targets"
store_path <- tempfile()
tar_config_set(store = store_path)
tar_config_get("store") # Shows a temp file.
tar_config_unset("store")
tar_config_get("store") # _targets
})
}

targets documentation built on Oct. 3, 2024, 1:11 a.m.