cranlike_metadata_cache | R Documentation |
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.
The cache has several layers:
The data is stored inside the cranlike_metadata_cache
object.
It is also stored as an RDS file, in the session temporary directory.
This ensures that the same data is used for all queries of a
cranlike_metadata_cache
object.
It is stored in an RDS file in the user's cache directory.
The downloaded raw PACKAGES*
files are cached, together with HTTP
ETags, to minimize downloads.
It has a synchronous and an asynchronous API.
cmc <- cranlike_metadata_cache$new( primary_path = NULL, replica_path = tempfile(), platforms = default_platforms(), r_version = getRversion(), bioc = TRUE, cran_mirror = default_cran_mirror(), repos = getOption("repos"), update_after = as.difftime(7, units = "days")) cmc$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$cleanup(force = FALSE)
primary_path
: Path of the primary, user level cache. Defaults to
the user level cache directory of the machine.
replica_path
: Path of the replica. Defaults to a temporary directory
within the session temporary directory.
platforms
: see default_platforms()
for possible values.
r_version
: R version to create the cache for.
bioc
: Whether to include BioConductor packages.
cran_mirror
: CRAN mirror to use, this takes precedence over repos
.
repos
: Repositories to use.
update_after
: difftime
object. Automatically update the cache if
it gets older than this. Set it to Inf
to avoid updates. Defaults
to seven days.
packages
: Packages to query, character vector.
dependencies
: Which kind of dependencies to include. Works the same
way as the dependencies
argument of utils::install.packages()
.
recursive
: Whether to include recursive dependencies.
force
: Whether to force cleanup without asking the user.
cranlike_metadata_cache$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$list()
lists all (or the specified) packages in the cache.
It returns a data frame, see the list of columns below.
cmc$async_list()
is similar, but it is asynchronous, it returns a
deferred
object.
cmc$deps()
returns a data frame, with the (potentially recursive)
dependencies of packages
.
cmc$async_deps()
is the same, but it is asynchronous, it
returns a deferred
object.
cmc$revdeps()
returns a data frame, with the (potentially recursive)
reverse dependencies of packages
.
cmc$async_revdeps()
does the same, asynchronously, it returns an
deferred
object.
cmc$update()
updates the the metadata (as needed) in the cache,
and then returns a data frame with all packages, invisibly.
cmc$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.
The metadata data frame 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
: This is a character vector. See default_platforms()
for
more about platform names. In practice each value of the platform
column is either
"source"
for source packages,
a platform string, e.g. x86_64-apple-darwin17.0
for macOS
packages compatible with macOS High Sierra or newer.
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 data frame.
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
normally not included in the list, so "base" should not appear here.)
md5sum
: MD5 sum, if available, may be NA
.
sysreqs
: The SystemRequirements
field, if available. This lists the
required system libraries or other software for the package. This is
usually available for CRAN and Bioconductor package and when it is
explicitly available in the repository metadata.
published
: The time the package was published at, in GMT,
POSIXct
class.
The data frame contains some extra columns as well, these are for internal use only.
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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