This is an R6 class that implements the metadata cache of a CRAN-like
repository. For a higher level interface, see the meta_cache_list(),
meta_cache_deps(), meta_cache_revdeps() and meta_cache_update()
functions.
cranlike_metadata_cacheAn object of class R6ClassGenerator of length 24.
cmc <- cranlike_metadata_cache$new(
primary_path = NULL, replica_path = tempfile(),
platforms = default_platforms(), r_version = current_r_version(),
bioc = TRUE, cran_mirror = default_cran_mirror(),
repos = getOption("repos"),
update_after = as.difftime(7, units = "days"))cmc$list(packages = NULL)
cmc$async_list(packages = NULL)
cmc$deps(packages, dependencies = NA, recursive = TRUE)
cmc$async_deps(packages, dependencies = NA, recursive = TRUE)
cmc$revdeps(packages, dependencies = NA, recursive = TRUE)
cmc$async_revdeps(packages, dependencies = NA, recursive = TRUE)
cmc$update()
cmc$async_update()
cmc$check_update()
cmc$asnyc_check_update()
cmc$summary()
cmc$cleanup(force = FALSE)
primary_path: Path of the primary, user level cache. Defaults to
the user level cache directory of the machine.
replica_path: Path of the replica. Defaults to a temporary directory
within the session temporary directory.
platforms: Subset of c("macos", "windows", "source"), platforms
to get data for.
r_version: R version to create the cache for.
bioc: Whether to include BioConductor packages.
cran_mirror: CRAN mirror to use, this takes precedence over repos.
repos: Repositories to use.
update_after: difftime object. Automatically update the cache if
it gets older than this. Set it to Inf to avoid updates. Defaults
to seven days.
packages: Packages to query, character vector.
dependencies: Which kind of dependencies to include. Works the same
way as the dependencies argument of utils::install.packages().
recursive: Whether to include recursive dependencies.
force: Whether to force cleanup without asking the user.
The metadata tibble contains all available versions (i.e. sources and binaries) for all packages. It usually has the following columns, some might be missing on some platforms.
package: Package name.
title: Package title.
version: Package version.
depends: Depends field from DESCRIPTION, or NA_character_.
suggests: Suggests field from DESCRIPTION, or NA_character_.
built: Built field from DESCIPTION, if a binary package,
or NA_character_.
imports: Imports field from DESCRIPTION, or NA_character_.
archs: Archs entries from PACKAGES files. Might be missing.
repodir: The directory of the file, inside the repository.
platform: Possible values: macos, windows, source.
needscompilation: Whether the package needs compilation.
type: bioc or cran currently.
target: The path of the package file inside the repository.
mirror: URL of the CRAN/BioC mirror.
sources: List column with URLs to one or more possible locations
of the package file. For source CRAN packages, it contains URLs to
the Archive directory as well, in case the package has been
archived since the metadata was cached.
filesize: Size of the file, if known, in bytes, or NA_integer_.
sha256: The SHA256 hash of the file, if known, or NA_character_.
deps: All package dependencies, in a tibble.
license: Package license, might be NA for binary packages.
linkingto: LinkingTo field from DESCRIPTION, or NA_character_.
enhances: Enhances field from DESCRIPTION, or NA_character_.
os_type: unix or windows for OS specific packages. Usually NA.
priority: "optional", "recommended" or NA. (Base packages are
normalliy not included in the list, so "base" should not appear here.)
md5sum: MD5 sum, if available, may be NA.
sysreqs: For CRAN packages, the SystemRequirements field, the
required system libraries or other software for the package. For
non-CRAN packages it is NA.
published: The time the package was published at, in GMT,
POSIXct class.
The tibble contains some extra columns as well, these are for internal use only.
cranlike_metadata_cache$new() creates a new cache object. Creation
does not trigger the population of the cache. It is only populated on
demand, when queries are executed against it. In your package, you may
want to create a cache instance in the .onLoad() function of the
package, and store it in the package namespace. As this is a cheap
operation, the package will still load fast, and then the package code
can refer to the common cache object.
cmc$list() lists all (or the specified) packages in the cache.
It returns a tibble, see the list of columns below.
cmc$async_list() is similar, but it is asynchronous, it returns a
deferred object.
cmc$deps() returns a tibble, with the (potentially recursive)
dependencies of packages.
cmc$async_deps() is the same, but it is asynchronous, it
returns a deferred object.
cmc$revdeps() returns a tibble, with the (potentially recursive)
reverse dependencies of packages.
cmc$async_revdeps() does the same, asynchronously, it returns an
deferred object.
cmc$update() updates the the metadata (as needed) in the cache,
and then returns a tibble with all packages, invisibly.
cmc$async_update() is similar, but it is asynchronous.
cmc$check_update() checks if the metadata is current, and if it is
not, it updates it.
cmc$async_check_update() is similar, but it is asynchronous.
cmc$summary() lists metadata about the cache, including its
location and size.
cmc$cleanup() deletes the cache files from the disk, and also from
memory.
# NOT RUN {
dir.create(cache_path <- tempfile())
cmc <- cranlike_metadata_cache$new(cache_path, bioc = FALSE)
cmc$list()
cmc$list("pkgconfig")
cmc$deps("pkgconfig")
cmc$revdeps("pkgconfig", recursive = FALSE)
# }
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