writePACKAGES: Generate PACKAGES Files

write_PACKAGESR Documentation

Generate PACKAGES Files

Description

Generate ‘PACKAGES’, ‘PACKAGES.gz’ and ‘PACKAGES.rds’ files for a repository of source or Mac/Windows binary packages.

Usage

write_PACKAGES(dir = ".", fields = NULL,
               type = c("source", "mac.binary", "win.binary"),
               verbose = FALSE, unpacked = FALSE, subdirs = FALSE,
               latestOnly = TRUE, addFiles = FALSE, rds_compress = "xz",
               validate = FALSE)

Arguments

dir

Character vector describing the location of the repository (directory including source or binary packages) to generate the ‘PACKAGES’, ‘PACKAGES.gz’ and ‘PACKAGES.rds’ files from and write them to.

fields

a character vector giving the fields to be used in the ‘PACKAGES’, ‘PACKAGES.gz’ and ‘PACKAGES.rds’ files in addition to the default ones, or NULL (default).

The default corresponds to the fields needed by available.packages: "Package", "Version", "Priority", "Depends", "Imports", "LinkingTo", "Suggests", "Enhances", "OS_type", "License" and "Archs", and those fields will always be included, plus the file name in field "File" if addFile = TRUE and the path to the subdirectory in field "Path" if subdirectories are used.

type

Type of packages: currently source ‘.tar.{gz,bz2,xz}’ archives, and macOS or Windows binary (‘.tgz’ or ‘.zip’, respectively) packages are supported. Defaults to "win.binary" on Windows and to "source" otherwise.

verbose

logical. Should packages be listed as they are processed?

unpacked

a logical indicating whether the package contents are available in unpacked form or not (default).

subdirs

either logical (to indicate if subdirectories should be included, recursively) or a character vector of names of subdirectories to include (which are not recursed).

latestOnly

logical: if multiple versions of a package are available should only the latest version be included?

addFiles

logical: should the filenames be included as field File in the ‘PACKAGES’ file.

rds_compress

The type of compression to be used for ‘PACKAGES.rds’: see saveRDS. The default is the one found to give maximal compression, and is as used on CRAN.

validate

a logical indicating whether ‘DESCRIPTION’ files should be validated, and the corresponding packages skipped in case this finds problems.

Details

write_PACKAGES scans the named directory for R packages, extracts information from each package's ‘DESCRIPTION’ file, and writes this information into the ‘PACKAGES’, ‘PACKAGES.gz’ and ‘PACKAGES.rds’ files, where the first two represent the information in DCF format, and the third serializes it via saveRDS.

Including non-latest versions of packages is only useful if they have less constraining version requirements, so for example latestOnly = FALSE could be used for a source repository when foo_1.0 depends on R >= 2.15.0 but foo_0.9 is available which depends on R >= 2.11.0.

Support for repositories with subdirectories and hence for subdirs != FALSE depends on recording a "Path" field in the ‘PACKAGES’ files.

Support for more general file names (e.g., other types of compression) via a "File" field in the ‘PACKAGES’ files can be used by download.packages. If the file names are not of the standard form, use addFiles = TRUE.

type = "win.binary" uses unz connections to read all ‘DESCRIPTION’ files contained in the (zipped) binary packages for Windows in the given directory dir, and builds files ‘PACKAGES’, ‘PACKAGES.gz’ and ‘PACKAGES.rds’ files from this information.

For a remote repository there is a tradeoff between download speed and time spent by available.packages processing the downloaded file(s). For large repositories it is likely to be beneficial to use rds_compress = "xz".

Value

Invisibly returns the number of packages described in the resulting ‘PACKAGES’, ‘PACKAGES.gz’ and ‘PACKAGES.rds’ files. If 0, no packages were found and no files were written.

Note

Processing ‘.tar.gz’ archives to extract the ‘DESCRIPTION’ files is quite slow.

This function can be useful on other OSes to prepare a repository to be accessed by Windows machines, so type = "win.binary" should work on all OSes.

Author(s)

Uwe Ligges and R-core.

See Also

See read.dcf and write.dcf for reading ‘DESCRIPTION’ files and writing the ‘PACKAGES’ and ‘PACKAGES.gz’ files. See update_PACKAGES for efficiently updating existing ‘PACKAGES’ and ‘PACKAGES.gz’ files.

Examples

## Not run: 
write_PACKAGES("c:/myFolder/myRepository")  # on Windows
write_PACKAGES("/pub/RWin/bin/windows/contrib/2.9",
               type = "win.binary")  # on Linux

## End(Not run)