Data package builds are controlled using the datapackager.yml file.
This file is created in the package source tree when the user creates a package using datapackage_skeleton().
It is automatically populated with the names of the code_files and data_objects the passed in to datapackage_skeleton.
datapackager.yml file.The structure of a correctly formatted datapackager.yml file is shown below:
configuration:
files:
subsetCars.Rmd:
enabled: yes
objects: cars_over_20
render_root:
tmp: '95772'The main section of the file is the configuration: section.
It has three properties:
files:
The files (R or Rmd) to be processed by DataPackageR. They are processed in the order shown. Users running multi-script workflows with dependencies between the scripts need to ensure the files are processed in the correct order.
Here subsetCars.Rmd is the only file to process. The name is transformed to an absolute path within the package.
Each file itself has just one property:
enabled: A logical yes, no flag indicating whether the file should be rendered during the build, or whether it should be skipped. This is useful for ‘turning off’ long running processing tasks if they have not changed. Disabling processing of a file will not overwrite existing documentation or data objecs created during previous builds.objects:
The names of the data objects created by the processing files, to be stored in the package. These names are compared against the objects created in the render environment by each file. They names must match.
render_root:
The directory where the Rmd or R files will be rendered. Defaults to a randomly named subdirectory of tempdir(). Allows workflows that use multiple scripts and create file system artifacts to function correctly by simply writing to and reading from the working directory.
The structure of the YAML is simple enough to understand but complex enough that it can be a pain to edit by hand.
DataPackageR provides a number of API calls to construct, read, modify, and write the yaml config file.
construct_yml_configMake an r object representing a YAML config file.
The YAML config shown above was created by:
# Note this is done by the datapackage_skeleton.
# The user doesn't usually need to call
# construct_yml_config()
yml <- DataPackageR::construct_yml_config(
code = "subsetCars.Rmd",
data = "cars_over_20"
)yml_findRead a yaml config file from a package path into an r object.
Read the YAML config file from the mtcars20 example.
# returns an r object representation of
# the config file.
mtcars20_config <- yml_find(
file.path(tempdir(),"mtcars20")
)yml_list_objectsList the objects in a config read by yml_find.
yml_list_objects(yml)
cars_over_20yml_list_filesList the files in a config read by yml_find.
yml_list_files(yml)
subsetCars.Rmdyml_disable_compileDisable compilation of named files in a config read by yml_find.
yml_disabled <- yml_disable_compile(
yml,
filenames = "subsetCars.Rmd")configuration:
files:
subsetCars.Rmd:
enabled: no
objects: cars_over_20
render_root:
tmp: '582114'yml_enable_compileEnable compilation of named files in a config read by yml_find.
yml_enabled <- yml_enable_compile(
yml,
filenames = "subsetCars.Rmd")configuration:
files:
subsetCars.Rmd:
enabled: yes
objects: cars_over_20
render_root:
tmp: '582114'yml_add_filesAdd named files to a config read by yml_find.
yml_twofiles <- yml_add_files(
yml,
filenames = "anotherFile.Rmd")configuration:
files:
subsetCars.Rmd:
enabled: yes
anotherFile.Rmd:
enabled: yes
objects: cars_over_20
render_root:
tmp: '582114'yml_add_objectsAdd named objects to a config read by yml_find.
yml_twoobj <- yml_add_objects(
yml_twofiles,
objects = "another_object")configuration:
files:
subsetCars.Rmd:
enabled: yes
anotherFile.Rmd:
enabled: yes
objects:
- cars_over_20
- another_object
render_root:
tmp: '582114'yml_remove_filesRemove named files from a config read by yml_find.
yml_twoobj <- yml_remove_files(
yml_twoobj,
filenames = "anotherFile.Rmd")configuration:
files:
subsetCars.Rmd:
enabled: yes
objects:
- cars_over_20
- another_object
render_root:
tmp: '582114'yml_remove_objectsRemove named objects from a config read by yml_find.
yml_oneobj <- yml_remove_objects(
yml_twoobj,
objects = "another_object")configuration:
files:
subsetCars.Rmd:
enabled: yes
objects: cars_over_20
render_root:
tmp: '582114'yml_writeWrite a modified config to its package path.
yml_write(yml_oneobj, path = "path_to_package")The yml_oneobj read by yml_find() carries an attribute that is the path to the package. The user doesn’t need to pass a path to yml_write if the config has been read by yml_find.