Purge individual line items from checksums file
.purge(
checkSums,
purge,
targetFile,
archive,
alsoExtract,
url,
destinationPath
)A checksums file, e.g., created by Checksums(..., write = TRUE)
Logical or Integer. 0/FALSE (default) keeps existing CHECKSUMS.txt file and
prepInputs will write or append to it. 1/TRUE will deleted the entire CHECKSUMS.txt file.
Other options, see details.
Character string giving the filename (without relative or
absolute path) to the eventual file
(raster, shapefile, csv, etc.) after downloading and extracting from a zip
or tar archive. This is the file before it is passed to
postProcess. The internal checksumming does not checksum
the file after it is postProcessed (e.g., cropped/reprojected/masked).
Using Cache around prepInputs will do a sufficient job in these cases.
See table in preProcess().
Optional character string giving the path of an archive
containing targetFile, or a vector giving a set of nested archives
(e.g., c("xxx.tar", "inner.zip", "inner.rar")). If there is/are (an) inner
archive(s), but they are unknown, the function will try all until it finds
the targetFile. See table in preProcess(). If it is NA,
then it will not attempt to see it as an archive, even if it has archive-like
file extension (e.g., .zip). This may be useful when an R function
is expecting an archive directly.
Which files to fetch or extract in addition to
targetFile. Spatial data rarely arrives as one file -- a shapefile is
five or six, and a raster often has a .aux.xml, .ovr or .tfw
alongside carrying its attribute table, overviews or georeferencing --
so this controls how much of that company comes along.
The default depends on where the files are coming from, because "everything" only means something when a container bounds it:
alsoExtract | from an archive | from a url |
NULL (default) | every file in the archive | as for "similar" |
"similar" | files sharing targetFile's name without its extension | same, discovered by listing the remote directory |
NA or "none" | targetFile only | targetFile only |
| a character vector | those files only | those files only |
An archive bounds what "all files" can mean, so NULL extracts all of it.
A url has no such bound -- the server may hold thousands of unrelated
files -- so NULL there means targetFile and its companions, never the
whole remote directory.
Each element of a character vector may also be a regular expression: if an
element does not match any archive member literally (by relative path or
basename), it is passed to grep() against the archive's file list and all
matching members are extracted. For example,
alsoExtract = "CMD_sm|CMD_sp" extracts every file whose name contains
CMD_sm or CMD_sp. See table in preProcess().
Optional character string indicating the URL to download from.
If not specified, then no download will be attempted. If not entry
exists in the CHECKSUMS.txt (in destinationPath), an entry
will be created or appended to. This CHECKSUMS.txt entry will be used
in subsequent calls to
prepInputs or preProcess, comparing the file on hand with the ad hoc
CHECKSUMS.txt. See table in preProcess().
Character string of a directory in which to download
and save the file that comes from url and is also where the function
will look for archive or targetFile.
To prevent repeated downloads in different locations, the user can also set
options("reproducible.destinationPathShared") to one or more local file paths to
search for the file before attempting to download. Default for that option is
NULL meaning do not search locally. The previous name
options("reproducible.inputPaths") is still accepted as a backwards-compatible
alias.